Replace InspIRCd::Format with fmt::format.

96 files changed, 349 insertions, 360 deletions

diff --git a/src/command_parse.cpp b/src/command_parse.cpp
index 98002f6f9..0460f60b7 100644
--- a/src/command_parse.cpp
+++ b/src/command_parse.cpp
@@ -280,8 +280,8 @@ void CommandParser::ProcessCommand(LocalUser* user, std::string& command, Comman
 			if (!user->HasCommandPermission(command))
 			{
 				user->CommandFloodPenalty += failpenalty;
-				user->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - Oper type %s does not have access to command %s",
-					user->oper->GetType().c_str(), command.c_str()));
+				user->WriteNumeric(ERR_NOPRIVILEGES, INSP_FORMAT("Permission Denied - Oper type {} does not have access to command {}",
+					user->oper->GetType(), command));
 				FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 				return;
 			}
diff --git a/src/configparser.cpp b/src/configparser.cpp
index fb70a2513..6dff45588 100644
--- a/src/configparser.cpp
+++ b/src/configparser.cpp
@@ -457,10 +457,7 @@ void ParseStack::DoReadFile(const std::string& key, const std::string& name, int
 
 	auto file = DoOpenFile(path, exec);
 	if (!file)
-	{
-		throw CoreException(InspIRCd::Format("Could not read \"%s\" for %s: %s",
-			path.c_str(), key.c_str(), strerror(errno)));
-	}
+		throw CoreException(INSP_FORMAT("Could not read \"{}\" for {}: {}", path, key, strerror(errno)));
 
 	file_cache& cache = FilesOutput[key];
 	cache.clear();
@@ -530,8 +527,7 @@ bool ParseStack::ParseFile(const std::string& path, int flags, const std::string
 		if (flags & FLAG_MISSING_OKAY)
 			return true;
 
-		throw CoreException(InspIRCd::Format("Could not read \"%s\" for include: %s",
-			path.c_str(), strerror(errno)));
+		throw CoreException(INSP_FORMAT("Could not read \"{}\" for include: {}", path, strerror(errno)));
 	}
 
 	reading.push_back(path);
diff --git a/src/configreader.cpp b/src/configreader.cpp
index 740bbd72a..937503e5b 100644
--- a/src/configreader.cpp
+++ b/src/configreader.cpp
@@ -32,7 +32,6 @@
 
 #include <filesystem>
 #include <iostream>
-
 #ifndef _WIN32
 # include <unistd.h>
 #endif
@@ -461,7 +460,7 @@ void ServerConfig::Apply(ServerConfig* old, const std::string& useruid)
 			std::cout << line << std::endl;
 		// If a user is rehashing, tell them directly
 		if (user)
-			user->WriteRemoteNotice(InspIRCd::Format("*** %s", line.c_str()));
+			user->WriteRemoteNotice(INSP_FORMAT("*** {}", line));
 		// Also tell opers
 		ServerInstance->SNO.WriteGlobalSno('r', line);
 	}
@@ -514,7 +513,7 @@ void ServerConfig::ApplyModules(User* user) const
 
 		if (ServerInstance->Modules.Unload(mod))
 		{
-			const std::string message = InspIRCd::Format("The %s module was unloaded.", modname.c_str());
+			const std::string message = INSP_FORMAT("The {} module was unloaded.", modname);
 			if (user)
 				user->WriteNumeric(RPL_UNLOADEDMODULE, modname, message);
 
@@ -522,7 +521,7 @@ void ServerConfig::ApplyModules(User* user) const
 		}
 		else
 		{
-			const std::string message = InspIRCd::Format("Failed to unload the %s module: %s", modname.c_str(), ServerInstance->Modules.LastError().c_str());
+			const std::string message = INSP_FORMAT("Failed to unload the {} module: {}", modname, ServerInstance->Modules.LastError());
 			if (user)
 				user->WriteNumeric(ERR_CANTUNLOADMODULE, modname, message);
 
@@ -538,7 +537,7 @@ void ServerConfig::ApplyModules(User* user) const
 
 		if (ServerInstance->Modules.Load(modname))
 		{
-			const std::string message = InspIRCd::Format("The %s module was loaded.", modname.c_str());
+			const std::string message = INSP_FORMAT("The {} module was loaded.", modname);
 			if (user)
 				user->WriteNumeric(RPL_LOADEDMODULE, modname, message);
 
@@ -546,7 +545,7 @@ void ServerConfig::ApplyModules(User* user) const
 		}
 		else
 		{
-			const std::string message = InspIRCd::Format("Failed to load the %s module: %s", modname.c_str(), ServerInstance->Modules.LastError().c_str());
+			const std::string message = INSP_FORMAT("Failed to load the {} module: {}", modname, ServerInstance->Modules.LastError());
 			if (user)
 				user->WriteNumeric(ERR_CANTLOADMODULE, modname, message);
 
diff --git a/src/coremods/core_channel/cmd_invite.cpp b/src/coremods/core_channel/cmd_invite.cpp
index f7e798294..ab2fe1ecb 100644
--- a/src/coremods/core_channel/cmd_invite.cpp
+++ b/src/coremods/core_channel/cmd_invite.cpp
@@ -190,7 +190,7 @@ CmdResult CommandInvite::Handle(User* user, const Params& parameters)
 		if (invapi.announceinvites != Invite::ANNOUNCE_NONE)
 		{
 			excepts.insert(user);
-			ClientProtocol::Messages::Privmsg privmsg(ServerInstance->FakeClient, c, InspIRCd::Format("*** %s invited %s into the channel", user->nick.c_str(), u->nick.c_str()), MessageType::NOTICE);
+			ClientProtocol::Messages::Privmsg privmsg(ServerInstance->FakeClient, c, INSP_FORMAT("*** {} invited {} into the channel", user->nick, u->nick), MessageType::NOTICE);
 			c->Write(ServerInstance->GetRFCEvents().privmsg, privmsg, prefix, excepts);
 		}
 	}
diff --git a/src/coremods/core_channel/core_channel.cpp b/src/coremods/core_channel/core_channel.cpp
index f95fb8c98..0b89fb83c 100644
--- a/src/coremods/core_channel/core_channel.cpp
+++ b/src/coremods/core_channel/core_channel.cpp
@@ -227,7 +227,7 @@ public:
 		std::string vlist;
 		for (auto* lm : ServerInstance->Modes.GetListModes())
 		{
-			limits.push_back(InspIRCd::Format("%c:%lu", lm->GetModeChar(), lm->GetLowerLimit()));
+			limits.push_back(INSP_FORMAT("{}:{}", lm->GetModeChar(), lm->GetLowerLimit()));
 			if (lm->HasVariableLength())
 				vlist.push_back(lm->GetModeChar());
 		}
@@ -240,7 +240,7 @@ public:
 
 	void OnBuildClassISupport(const std::shared_ptr<ConnectClass>& klass, ISupport::TokenMap& tokens) override
 	{
-		tokens["CHANLIMIT"] = InspIRCd::Format("#:%lu", klass->maxchans);
+		tokens["CHANLIMIT"] = INSP_FORMAT("#:{}", klass->maxchans);
 	}
 
 	ModResult OnUserPreJoin(LocalUser* user, Channel* chan, const std::string& cname, std::string& privs, const std::string& keygiven, bool override) override
diff --git a/src/coremods/core_dns.cpp b/src/coremods/core_dns.cpp
index 57d05c63e..9d9e887ff 100644
--- a/src/coremods/core_dns.cpp
+++ b/src/coremods/core_dns.cpp
@@ -19,6 +19,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+
 #include "inspircd.h"
 #include "modules/dns.h"
 #include "modules/stats.h"
@@ -233,7 +234,7 @@ private:
 				if (!InspIRCd::IsHost(srv->host, true))
 					throw Exception(creator, "Invalid name in SRV resource record");
 
-				record.rdata = InspIRCd::Format("%u %u %u %s", srv->priority, srv->weight, srv->port, srv->host.c_str());
+				record.rdata = INSP_FORMAT("{} {} {} {}", srv->priority, srv->weight, srv->port, srv->host);
 				record.rdataobj = srv;
 				break;
 			}
@@ -931,7 +932,7 @@ public:
 	{
 		if (stats.GetSymbol() == 'T')
 		{
-			stats.AddGenericRow(InspIRCd::Format("DNS requests: %zu (%zu succeeded, %zu failed)",
+			stats.AddGenericRow(INSP_FORMAT("DNS requests: {} ({} succeeded, {} failed)",
 				manager.stats_total, manager.stats_success, manager.stats_failure));
 		}
 		return MOD_RES_PASSTHRU;
diff --git a/src/coremods/core_info/cmd_motd.cpp b/src/coremods/core_info/cmd_motd.cpp
index 60e43b2e2..1f7bf75f8 100644
--- a/src/coremods/core_info/cmd_motd.cpp
+++ b/src/coremods/core_info/cmd_motd.cpp
@@ -64,7 +64,7 @@ CmdResult CommandMotd::Handle(User* user, const Params& parameters)
 		return CmdResult::SUCCESS;
 	}
 
-	user->WriteRemoteNumeric(RPL_MOTDSTART, InspIRCd::Format("%s message of the day:", ServerInstance->Config->GetServerName().c_str()));
+	user->WriteRemoteNumeric(RPL_MOTDSTART, INSP_FORMAT("{} message of the day:", ServerInstance->Config->GetServerName()));
 	for (const auto& line : motd->second)
 		user->WriteRemoteNumeric(RPL_MOTD, line);
 	user->WriteRemoteNumeric(RPL_ENDOFMOTD, "End of message of the day.");
diff --git a/src/coremods/core_info/core_info.cpp b/src/coremods/core_info/core_info.cpp
index 61799232b..ad09ac73c 100644
--- a/src/coremods/core_info/core_info.cpp
+++ b/src/coremods/core_info/core_info.cpp
@@ -174,8 +174,8 @@ public:
 
 	void OnUserConnect(LocalUser* user) override
 	{
-		user->WriteNumeric(RPL_WELCOME, InspIRCd::Format("Welcome to the %s IRC Network %s", ServerInstance->Config->Network.c_str(), user->GetFullRealHost().c_str()));
-		user->WriteNumeric(RPL_YOURHOST, InspIRCd::Format("Your host is %s, running version %s", ServerInstance->Config->GetServerName().c_str(), INSPIRCD_BRANCH));
+		user->WriteNumeric(RPL_WELCOME, INSP_FORMAT("Welcome to the {} IRC Network {}", ServerInstance->Config->Network, user->GetFullRealHost()));
+		user->WriteNumeric(RPL_YOURHOST, INSP_FORMAT("Your host is {}, running version {}", ServerInstance->Config->GetServerName(), INSPIRCD_BRANCH));
 		user->WriteNumeric(RPL_CREATED, InspIRCd::TimeString(ServerInstance->startup_time, "This server was created %H:%M:%S %b %d %Y"));
 		user->WriteNumeric(numeric004);
 		isupport.SendTo(user);
diff --git a/src/coremods/core_info/isupport.cpp b/src/coremods/core_info/isupport.cpp
index ec237c017..d28ae8675 100644
--- a/src/coremods/core_info/isupport.cpp
+++ b/src/coremods/core_info/isupport.cpp
@@ -65,7 +65,7 @@ void ISupportManager::AppendValue(std::string& buffer, const std::string& value)
 		//   (1) It is a banned character in an IRC <middle> parameter (NUL, LF, CR, SPACE).
 		//   (2) It has special meaning within an ISUPPORT token (EQUALS, BACKSLASH).
 		if (chr == '\0' || chr == '\n' || chr == '\r' || chr == ' ' || chr == '=' || chr == '\\')
-			buffer.append(InspIRCd::Format("\\x%X", chr));
+			buffer.append(INSP_FORMAT("\\x{:02X}", chr));
 		else
 			buffer.push_back(chr);
 	}
diff --git a/src/coremods/core_list.cpp b/src/coremods/core_list.cpp
index 1daa4b4a7..a7d8255c4 100644
--- a/src/coremods/core_list.cpp
+++ b/src/coremods/core_list.cpp
@@ -171,7 +171,7 @@ CmdResult CommandList::Handle(User* user, const Params& parameters)
 			else if (showmodes)
 			{
 				// Show the list response with the modes and topic.
-				user->WriteNumeric(RPL_LIST, chan->name, users, InspIRCd::Format("[+%s] %s", chan->ChanModes(n), chan->topic.c_str()));
+				user->WriteNumeric(RPL_LIST, chan->name, users, INSP_FORMAT("[+{}] {}", chan->ChanModes(n), chan->topic));
 			}
 			else
 			{
diff --git a/src/coremods/core_lusers.cpp b/src/coremods/core_lusers.cpp
index 4b8fddfa0..d57f183ce 100644
--- a/src/coremods/core_lusers.cpp
+++ b/src/coremods/core_lusers.cpp
@@ -103,7 +103,7 @@ CmdResult CommandLusers::Handle(User* user, const Params& parameters)
 
 	counters.UpdateMaxUsers();
 
-	user->WriteNumeric(RPL_LUSERCLIENT, InspIRCd::Format("There are %zu users and %zu invisible on %zu servers",
+	user->WriteNumeric(RPL_LUSERCLIENT, INSP_FORMAT("There are {} users and {} invisible on {} servers",
 			n_users - counters.invisible, counters.invisible, n_serv));
 
 	size_t opercount = ServerInstance->Users.all_opers.size();
@@ -114,9 +114,9 @@ CmdResult CommandLusers::Handle(User* user, const Params& parameters)
 		user->WriteNumeric(RPL_LUSERUNKNOWN, ServerInstance->Users.UnknownUserCount(), "unknown connections");
 
 	user->WriteNumeric(RPL_LUSERCHANNELS, ServerInstance->Channels.GetChans().size(), "channels formed");
-	user->WriteNumeric(RPL_LUSERME, InspIRCd::Format("I have %zu clients and %zu servers", ServerInstance->Users.LocalUserCount(), n_local_servs));
-	user->WriteNumeric(RPL_LOCALUSERS, InspIRCd::Format("Current local users: %zu  Max: %zu", ServerInstance->Users.LocalUserCount(), counters.max_local));
-	user->WriteNumeric(RPL_GLOBALUSERS, InspIRCd::Format("Current global users: %zu  Max: %zu", n_users, counters.max_global));
+	user->WriteNumeric(RPL_LUSERME, INSP_FORMAT("I have {} clients and {} servers", ServerInstance->Users.LocalUserCount(), n_local_servs));
+	user->WriteNumeric(RPL_LOCALUSERS, INSP_FORMAT("Current local users: {}  Max: {}", ServerInstance->Users.LocalUserCount(), counters.max_local));
+	user->WriteNumeric(RPL_GLOBALUSERS, INSP_FORMAT("Current global users: {}  Max: {}", n_users, counters.max_global));
 	return CmdResult::SUCCESS;
 }
 
diff --git a/src/coremods/core_mode.cpp b/src/coremods/core_mode.cpp
index 63e7a4708..c64124955 100644
--- a/src/coremods/core_mode.cpp
+++ b/src/coremods/core_mode.cpp
@@ -348,7 +348,7 @@ private:
 		std::sort(type3.begin(), type3.end());
 		std::sort(type4.begin(), type4.end());
 
-		return InspIRCd::Format("%s,%s,%s,%s", type1.c_str(), type2.c_str(), type3.c_str(), type4.c_str());
+		return INSP_FORMAT("{},{},{},{}", type1, type2, type3, type4);
 	}
 
 	static std::string GeneratePrefixList(bool includemodechars)
diff --git a/src/coremods/core_oper/cmd_oper.cpp b/src/coremods/core_oper/cmd_oper.cpp
index c077b277f..10e098019 100644
--- a/src/coremods/core_oper/cmd_oper.cpp
+++ b/src/coremods/core_oper/cmd_oper.cpp
@@ -31,8 +31,7 @@ namespace
 {
 	CmdResult FailedOper(LocalUser* user, const std::string& name)
 	{
-		user->WriteNumeric(ERR_NOOPERHOST, InspIRCd::Format("Failed to log into the \x02%s\x02 oper account (check the server log for details).",
-			name.c_str()));
+		user->WriteNumeric(ERR_NOOPERHOST, INSP_FORMAT("Failed to log into the \x02{}\x02 oper account (check the server log for details).", name));
 		user->CommandFloodPenalty += 10'000;
 		return CmdResult::FAILURE;
 	}
diff --git a/src/coremods/core_oper/core_oper.cpp b/src/coremods/core_oper/core_oper.cpp
index d7a8c9760..1a8d40925 100644
--- a/src/coremods/core_oper/core_oper.cpp
+++ b/src/coremods/core_oper/core_oper.cpp
@@ -101,9 +101,8 @@ public:
 		if (!luser)
 			return;
 
-		luser->WriteNumeric(RPL_YOUAREOPER, InspIRCd::Format("You are now %s %s",
-			strchr("AEIOUaeiou", user->oper->GetType()[0]) ? "an" : "a",
-			user->oper->GetType().c_str()));
+		luser->WriteNumeric(RPL_YOUAREOPER, INSP_FORMAT("You are now {} {}", strchr("AEIOUaeiou", user->oper->GetType()[0]) ? "an" : "a",
+			user->oper->GetType()));
 
 		ServerInstance->SNO.WriteToSnoMask('o', "%s (%s) [%s] is now a server operator of type \x02%s\x02 (%susing account \x02%s\x02).",
 			user->nick.c_str(), user->MakeHost().c_str(), user->GetIPString().c_str(), user->oper->GetType().c_str(),
@@ -143,13 +142,12 @@ public:
 					const std::string commands = account->GetCommands();
 					const std::string privileges = account->GetPrivileges();
 
-					stats.AddGenericRow(InspIRCd::Format(
-						"\x02%s\x02 (hosts: %s, type: %s, channel modes: %s, user modes: %s, snomasks: %s, commands: %s, privileges: %s)",
-						account->GetName().c_str(), NoneIfEmpty(hosts).c_str(), account->GetType().c_str(),
-						NoneIfEmpty(chanmodes).c_str(), NoneIfEmpty(usermodes).c_str(),
-						NoneIfEmpty(snomasks).c_str(), NoneIfEmpty(commands).c_str(),
-						NoneIfEmpty(privileges).c_str())
-					).AddTags(stats, {
+					stats.AddGenericRow(INSP_FORMAT(
+						"\x02{}\x02 (hosts: {}, type: {}, channel modes: {}, user modes: {}, snomasks: {}, commands: {}, privileges: {})",
+						account->GetName(), NoneIfEmpty(hosts), account->GetType(), NoneIfEmpty(chanmodes), NoneIfEmpty(usermodes),
+						NoneIfEmpty(snomasks), NoneIfEmpty(commands), NoneIfEmpty(privileges)
+					))
+					.AddTags(stats, {
 						{ "name",       account->GetName() },
 						{ "hosts",      hosts              },
 						{ "chan-modes", chanmodes          },
@@ -173,12 +171,12 @@ public:
 					const std::string commands = type->GetCommands();
 					const std::string privileges = type->GetPrivileges();
 
-					stats.AddGenericRow(InspIRCd::Format(
-						"\x02%s\02 (channel modes: %s, user modes: %s, snomasks: %s, commands: %s, privileges: %s)",
-						type->GetName().c_str(), NoneIfEmpty(chanmodes).c_str(),
-						NoneIfEmpty(usermodes).c_str(), NoneIfEmpty(snomasks).c_str(),
-						NoneIfEmpty(commands).c_str(), NoneIfEmpty(privileges).c_str())
-					).AddTags(stats, {
+					stats.AddGenericRow(INSP_FORMAT(
+						"\x02{}\02 (channel modes: {}, user modes: {}, snomasks: {}, commands: {}, privileges: {})",
+						type->GetName(), NoneIfEmpty(chanmodes), NoneIfEmpty(usermodes), NoneIfEmpty(snomasks),
+						NoneIfEmpty(commands), NoneIfEmpty(privileges)
+					))
+					.AddTags(stats, {
 						{ "name",       type->GetName()  },
 						{ "chan-modes", chanmodes        },
 						{ "user-modes", usermodes        },
@@ -205,8 +203,8 @@ public:
 					{
 						const std::string awayperiod = Duration::ToString(ServerInstance->Time() - oper->awaytime);
 						const std::string awaytime = InspIRCd::TimeString(oper->awaytime);
-						extra += InspIRCd::Format(": away for %s [since %s] (%s)", awayperiod.c_str(),
-							awaytime.c_str(), oper->awaymsg.c_str());
+
+						extra = INSP_FORMAT(": away for {} [since {}] ({})", awayperiod, awaytime, oper->awaymsg);
 					}
 
 					auto* loper = IS_LOCAL(oper);
@@ -214,14 +212,13 @@ public:
 					{
 						const std::string idleperiod = Duration::ToString(ServerInstance->Time() - loper->idle_lastmsg);
 						const std::string idletime = InspIRCd::TimeString(loper->idle_lastmsg);
-						extra += InspIRCd::Format("%c idle for %s [since %s]",  extra.empty() ? ':' : ',',
-							idleperiod.c_str(), idletime.c_str());
+
+						extra += INSP_FORMAT("{} idle for {} [since {}]",  extra.empty() ? ':' : ',', idleperiod, idletime);
 					}
 
-					stats.AddGenericRow(InspIRCd::Format("\x02%s\x02 (%s)%s", oper->nick.c_str(),
-						oper->MakeHost().c_str(), extra.c_str()));
+					stats.AddGenericRow(INSP_FORMAT("\x02{}\x02 ({}){}", oper->nick, oper->MakeHost(), extra));
 				}
-				stats.AddGenericRow(InspIRCd::Format("%zu server operator%s total", opers, opers ? "s" : ""));
+				stats.AddGenericRow(INSP_FORMAT("{} server operator{} total", opers, opers ? "s" : ""));
 				return MOD_RES_DENY;
 			}
 		}
diff --git a/src/coremods/core_oper/umode_s.cpp b/src/coremods/core_oper/umode_s.cpp
index c7562a744..ac99aa9f4 100644
--- a/src/coremods/core_oper/umode_s.cpp
+++ b/src/coremods/core_oper/umode_s.cpp
@@ -106,15 +106,15 @@ std::string ModeUserServerNoticeMask::ProcessNoticeMasks(User* user, const std::
 					}
 					else if (!user->IsOper())
 					{
-						user->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - Only operators may %sset snomask %c",
-							adding ? "" : "un", snomask));
+						user->WriteNumeric(ERR_NOPRIVILEGES, INSP_FORMAT("Permission Denied - Only operators may {} snomask {}",
+							adding ? "set" : "unset", snomask));
 						continue;
 
 					}
 					else if (!user->HasSnomaskPermission(snomask))
 					{
-						user->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - Oper type %s does not have access to snomask %c",
-							user->oper->GetType().c_str(), snomask));
+						user->WriteNumeric(ERR_NOPRIVILEGES, INSP_FORMAT("Permission Denied - Oper type {} does not have access to snomask {}",
+							user->oper->GetType(), snomask));
 						continue;
 					}
 				}
diff --git a/src/coremods/core_reloadmodule.cpp b/src/coremods/core_reloadmodule.cpp
index 1c00ed390..8ebabc7be 100644
--- a/src/coremods/core_reloadmodule.cpp
+++ b/src/coremods/core_reloadmodule.cpp
@@ -710,9 +710,9 @@ public:
 		if (user)
 		{
 			if (result)
-				user->WriteNumeric(RPL_LOADEDMODULE, passedname, InspIRCd::Format("The %s module was reloaded.", passedname.c_str()));
+				user->WriteNumeric(RPL_LOADEDMODULE, passedname, INSP_FORMAT("The {} module was reloaded.", passedname));
 			else
-				user->WriteNumeric(ERR_CANTUNLOADMODULE, passedname, InspIRCd::Format("Failed to reload the %s module.", passedname.c_str()));
+				user->WriteNumeric(ERR_CANTUNLOADMODULE, passedname, INSP_FORMAT("Failed to reload the {} module.", passedname));
 		}
 
 		ServerInstance->GlobalCulls.AddItem(this);
diff --git a/src/coremods/core_stats.cpp b/src/coremods/core_stats.cpp
index 303c1d346..d2d8fb8b7 100644
--- a/src/coremods/core_stats.cpp
+++ b/src/coremods/core_stats.cpp
@@ -26,11 +26,6 @@
  */
 
 
-#include "inspircd.h"
-#include "xline.h"
-#include "modules/cap.h"
-#include "modules/stats.h"
-
 #ifdef _WIN32
 # include <psapi.h>
 #else
@@ -38,6 +33,11 @@
 # include <sys/resource.h>
 #endif
 
+#include "inspircd.h"
+#include "modules/cap.h"
+#include "modules/stats.h"
+#include "xline.h"
+
 class StatsTagsProvider
 	: public ClientProtocol::MessageTagProvider
 {
@@ -91,7 +91,7 @@ public:
 
 static void GenerateStatsLl(Stats::Context& stats)
 {
-	stats.AddRow(211, InspIRCd::Format("nick[ident@%s] sendq cmds_out bytes_out cmds_in bytes_in time_open", (stats.GetSymbol() == 'l' ? "host" : "ip")));
+	stats.AddRow(211, INSP_FORMAT("nick[ident@{}] sendq cmds_out bytes_out cmds_in bytes_in time_open", stats.GetSymbol() == 'l' ? "host" : "ip"));
 
 	for (auto* u : ServerInstance->Users.GetLocalUsers())
 		stats.AddRow(211, u->nick+"["+u->ident+"@"+(stats.GetSymbol() == 'l' ? u->GetDisplayedHost() : u->GetIPString())+"] "+ConvToStr(u->eh.GetSendQSize())+" "+ConvToStr(u->cmds_out)+" "+ConvToStr(u->bytes_out)+" "+ConvToStr(u->cmds_in)+" "+ConvToStr(u->bytes_in)+" "+ConvToStr(ServerInstance->Time() - u->signon));
@@ -257,9 +257,9 @@ void CommandStats::DoStats(Stats::Context& stats)
 			float kbitpersec_total;
 			SocketEngine::GetStats().GetBandwidth(kbitpersec_in, kbitpersec_out, kbitpersec_total);
 
-			stats.AddRow(249, InspIRCd::Format("Bandwidth total:  %03.5f kilobits/sec", kbitpersec_total));
-			stats.AddRow(249, InspIRCd::Format("Bandwidth out:    %03.5f kilobits/sec", kbitpersec_out));
-			stats.AddRow(249, InspIRCd::Format("Bandwidth in:     %03.5f kilobits/sec", kbitpersec_in));
+			stats.AddRow(249, INSP_FORMAT("Bandwidth total:  {:03.5} kilobits/sec", kbitpersec_total));
+			stats.AddRow(249, INSP_FORMAT("Bandwidth out:    {:03.5} kilobits/sec", kbitpersec_out));
+			stats.AddRow(249, INSP_FORMAT("Bandwidth in:     {:03.5} kilobits/sec", kbitpersec_in));
 
 #ifndef _WIN32
 			/* Moved this down here so all the not-windows stuff (look w00tie, I didn't say win32!) is in one ifndef.
@@ -282,13 +282,13 @@ void CommandStats::DoStats(Stats::Context& stats)
 				float n_eaten = ((R.ru_utime.tv_sec - ServerInstance->stats.LastCPU.tv_sec) * 1000000 + R.ru_utime.tv_usec - ServerInstance->stats.LastCPU.tv_usec);
 				float per = (n_eaten / n_elapsed) * 100;
 
-				stats.AddRow(249, InspIRCd::Format("CPU Use (now):    %03.5f%%", per));
+				stats.AddRow(249, INSP_FORMAT("CPU Use (now):    {:03.5}%", per));
 
 				n_elapsed = ServerInstance->Time() - ServerInstance->startup_time;
 				n_eaten = (float)R.ru_utime.tv_sec + R.ru_utime.tv_usec / 100000.0;
 				per = (n_eaten / n_elapsed) * 100;
 
-				stats.AddRow(249, InspIRCd::Format("CPU Use (total):  %03.5f%%", per));
+				stats.AddRow(249, INSP_FORMAT("CPU Use (total):  {:03.5}%", per));
 			}
 #else
 			PROCESS_MEMORY_COUNTERS MemCounters;
@@ -313,13 +313,13 @@ void CommandStats::DoStats(Stats::Context& stats)
 				double n_elapsed = (double)(ThisSample.QuadPart - ServerInstance->stats.LastSampled.QuadPart) / ServerInstance->stats.QPFrequency.QuadPart;
 				double per = (n_eaten/n_elapsed);
 
-				stats.AddRow(249, InspIRCd::Format("CPU Use (now):    %03.5f%%", per));
+				stats.AddRow(249, INSP_FORMAT("CPU Use (now):    {:03.5}%", per));
 
 				n_elapsed = ServerInstance->Time() - ServerInstance->startup_time;
 				n_eaten = (double)(( (uint64_t)(KernelTime.dwHighDateTime) << 32 ) + (uint64_t)(KernelTime.dwLowDateTime))/100000;
 				per = (n_eaten / n_elapsed);
 
-				stats.AddRow(249, InspIRCd::Format("CPU Use (total):  %03.5f%%", per));
+				stats.AddRow(249, INSP_FORMAT("CPU Use (total):  {:03.5}%", per));
 			}
 #endif
 		}
@@ -331,7 +331,7 @@ void CommandStats::DoStats(Stats::Context& stats)
 			stats.AddRow(249, "unknown commands "+ConvToStr(ServerInstance->stats.Unknown));
 			stats.AddRow(249, "nick collisions "+ConvToStr(ServerInstance->stats.Collisions));
 			stats.AddRow(249, "connection count "+ConvToStr(ServerInstance->stats.Connects));
-			stats.AddRow(249, InspIRCd::Format("bytes sent %5.2fK recv %5.2fK",
+			stats.AddRow(249, INSP_FORMAT("bytes sent {:5.2}K recv {:5.2}K",
 				ServerInstance->stats.Sent / 1024.0, ServerInstance->stats.Recv / 1024.0));
 		}
 		break;
@@ -347,7 +347,7 @@ void CommandStats::DoStats(Stats::Context& stats)
 		case 'u':
 		{
 			unsigned int up = static_cast<unsigned int>(ServerInstance->Time() - ServerInstance->startup_time);
-			stats.AddRow(242, InspIRCd::Format("Server up %u days, %.2u:%.2u:%.2u",
+			stats.AddRow(242, INSP_FORMAT("Server up {} days, {:02}:{:02}:{:02}",
 				up / 86400, (up / 3600) % 24, (up / 60) % 60, up % 60));
 		}
 		break;
diff --git a/src/coremods/core_stub.cpp b/src/coremods/core_stub.cpp
index 278cf05b7..c2ef88af8 100644
--- a/src/coremods/core_stub.cpp
+++ b/src/coremods/core_stub.cpp
@@ -85,7 +85,7 @@ public:
 
 	CmdResult Handle(User* user, const Params& parameters) override
 	{
-		user->WriteNumeric(RPL_LINKS, ServerInstance->Config->GetServerName(), ServerInstance->Config->GetServerName(), InspIRCd::Format("0 %s", ServerInstance->Config->GetServerDesc().c_str()));
+		user->WriteNumeric(RPL_LINKS, ServerInstance->Config->GetServerName(), ServerInstance->Config->GetServerName(), INSP_FORMAT("0 {}", ServerInstance->Config->GetServerDesc()));
 		user->WriteNumeric(RPL_ENDOFLINKS, '*', "End of /LINKS list.");
 		return CmdResult::SUCCESS;
 	}
diff --git a/src/coremods/core_user/cmd_nick.cpp b/src/coremods/core_user/cmd_nick.cpp
index 6683e1e40..e40699e4e 100644
--- a/src/coremods/core_user/cmd_nick.cpp
+++ b/src/coremods/core_user/cmd_nick.cpp
@@ -81,8 +81,8 @@ CmdResult CommandNick::HandleLocal(LocalUser* user, const Params& parameters)
 			if (memb->chan->GetPrefixValue(user) < VOICE_VALUE && memb->chan->IsBanned(user))
 			{
 				if (ServerInstance->Config->RestrictBannedUsers == ServerConfig::BUT_RESTRICT_NOTIFY)
-					user->WriteNumeric(ERR_CANTCHANGENICK, InspIRCd::Format("Cannot change nickname while on %s (you're banned)",
-						memb->chan->name.c_str()));
+					user->WriteNumeric(ERR_CANTCHANGENICK, INSP_FORMAT("Cannot change nickname while on {} (you're banned)",
+						memb->chan->name));
 				return CmdResult::FAILURE;
 			}
 		}
diff --git a/src/coremods/core_whois.cpp b/src/coremods/core_whois.cpp
index 8ee7969fc..ae2c31cfc 100644
--- a/src/coremods/core_whois.cpp
+++ b/src/coremods/core_whois.cpp
@@ -25,7 +25,6 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-
 #include "inspircd.h"
 #include "modules/whois.h"
 #include "numericbuilder.h"
@@ -227,18 +226,18 @@ void CommandWhois::DoWhois(LocalUser* user, User* dest, time_t signon, unsigned
 		if (genericoper)
 			whois.SendLine(RPL_WHOISOPERATOR, dest->server->IsService() ? "is a network service" : "is a server operator");
 		else
-			whois.SendLine(RPL_WHOISOPERATOR, InspIRCd::Format("is %s %s on %s", (strchr("AEIOUaeiou", dest->oper->GetType()[0]) ? "an" : "a"), dest->oper->GetType().c_str(), ServerInstance->Config->Network.c_str()));
+			whois.SendLine(RPL_WHOISOPERATOR, INSP_FORMAT("is {} {} on {}", (strchr("AEIOUaeiou", dest->oper->GetType()[0]) ? "an" : "a"), dest->oper->GetType(), ServerInstance->Config->Network));
 	}
 
 	if (whois.IsSelfWhois() || user->HasPrivPermission("users/auspex"))
 	{
 		if (dest->IsModeSet(snomaskmode))
 		{
-			whois.SendLine(RPL_WHOISMODES, InspIRCd::Format("is using modes %s %s", dest->GetModeLetters().c_str(), snomaskmode->GetUserParameter(dest).c_str()));
+			whois.SendLine(RPL_WHOISMODES, INSP_FORMAT("is using modes {} {}", dest->GetModeLetters(), snomaskmode->GetUserParameter(dest)));
 		}
 		else
 		{
-			whois.SendLine(RPL_WHOISMODES, InspIRCd::Format("is using modes %s", dest->GetModeLetters().c_str()));
+			whois.SendLine(RPL_WHOISMODES, INSP_FORMAT("is using modes {}", dest->GetModeLetters()));
 		}
 	}
 
diff --git a/src/coremods/core_whowas.cpp b/src/coremods/core_whowas.cpp
index 342bbffd5..21ada0af5 100644
--- a/src/coremods/core_whowas.cpp
+++ b/src/coremods/core_whowas.cpp
@@ -227,7 +227,7 @@ CmdResult CommandWhowas::Handle(User* user, const Params& parameters)
 			user->WriteNumeric(RPL_WHOWASUSER, parameters[0], u->ident, u->dhost, '*', u->real);
 
 			if (user->HasPrivPermission("users/auspex"))
-				user->WriteNumeric(RPL_WHOWASIP, parameters[0], InspIRCd::Format("was connecting from *@%s", u->host.c_str()));
+				user->WriteNumeric(RPL_WHOWASIP, parameters[0], INSP_FORMAT("was connecting from *@{}", u->host));
 
 			std::string signon = InspIRCd::TimeString(u->signon);
 			bool hide_server = (!ServerInstance->Config->HideServer.empty() && !user->HasPrivPermission("servers/auspex"));
diff --git a/src/coremods/core_xline/core_xline.cpp b/src/coremods/core_xline/core_xline.cpp
index d4b29614d..4218abd6c 100644
--- a/src/coremods/core_xline/core_xline.cpp
+++ b/src/coremods/core_xline/core_xline.cpp
@@ -45,7 +45,7 @@ bool InsaneBan::MatchesEveryone(const std::string& mask, MatcherBase& test, User
 		const char* article = strchr("AEIOUaeiou", bantype) ? "an" : "a";
 		ServerInstance->SNO.WriteToSnoMask('x', "\002WARNING\002: %s tried to set add %s %c-line on %s which covers %.2f%% of the network which is more than the maximum of %.2f%%!",
 			user->nick.c_str(), article, bantype, mask.c_str(), percent, itrigger);
-		user->WriteNotice(InspIRCd::Format("*** Unable to add %s %c-line on %s which covers %.2f%% of the network which is more than the maximum of %.2f%%!",
+		user->WriteNotice(INSP_FORMAT("*** Unable to add {} {}-line on {} which covers {:.2}% of the network which is more than the maximum of {:.2}%!",
 			article, bantype, mask.c_str(), percent, itrigger));
 		return true;
 	}
@@ -157,7 +157,7 @@ public:
 		}
 
 		// Send a numeric because if we deny then the core doesn't reply anything
-		user->WriteNumeric(ERR_ERRONEUSNICKNAME, newnick, InspIRCd::Format("Invalid nickname: %s", xline->reason.c_str()));
+		user->WriteNumeric(ERR_ERRONEUSNICKNAME, newnick, INSP_FORMAT("Invalid nickname: {}", xline->reason));
 		return MOD_RES_DENY;
 	}
 
diff --git a/src/dynamic.cpp b/src/dynamic.cpp
index 50b46f5b2..dcc7d00c9 100644
--- a/src/dynamic.cpp
+++ b/src/dynamic.cpp
@@ -25,14 +25,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-
-#include "inspircd.h"
-#include "dynamic.h"
-
 #ifndef _WIN32
 # include <dlfcn.h>
 #endif
 
+#include "inspircd.h"
+#include "dynamic.h"
+
 DLLManager::DLLManager(const std::string& name)
 	: libname(name)
 {
@@ -79,8 +78,8 @@ Module* DLLManager::CallInit()
 	else if (*abi != MODULE_ABI)
 	{
 		const char* version = GetVersion();
-		err.assign(InspIRCd::Format("%s was built against %s (%lu) which is too %s to use with %s (%lu).",
-			libname.c_str(), version ? version : "an unknown version", *abi,
+		err.assign(INSP_FORMAT("{} was built against {} ({}) which is too {} to use with {} ({}).",
+			libname, version ? version : "an unknown version", *abi,
 			*abi < MODULE_ABI ? "old" : "new", INSPIRCD_VERSION, MODULE_ABI));
 		return nullptr;
 	}
diff --git a/src/helperfuncs.cpp b/src/helperfuncs.cpp
index 260a19a0b..98ce2fed4 100644
--- a/src/helperfuncs.cpp
+++ b/src/helperfuncs.cpp
@@ -410,13 +410,6 @@ std::string InspIRCd::Format(va_list& vaList, const char* formatString)
 	return std::string(formatBuffer.data());
 }
 
-std::string InspIRCd::Format(const char* formatString, ...)
-{
-	std::string ret;
-	VAFORMAT(ret, formatString, formatString);
-	return ret;
-}
-
 std::string InspIRCd::TimeString(time_t curtime, const char* format, bool utc)
 {
 #ifdef _WIN32
diff --git a/src/listmode.cpp b/src/listmode.cpp
index 4fd77d7f0..01f70836a 100644
--- a/src/listmode.cpp
+++ b/src/listmode.cpp
@@ -19,6 +19,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+
 #include "inspircd.h"
 #include "listmode.h"
 
@@ -50,12 +51,12 @@ void ListModeBase::DisplayList(User* user, Channel* channel)
 	for (const auto& item : cd->list)
 		user->WriteNumeric(listnumeric, channel->name, item.mask, item.setter, item.time);
 
-	user->WriteNumeric(endoflistnumeric, channel->name, InspIRCd::Format("End of channel %s list.", name.c_str()));
+	user->WriteNumeric(endoflistnumeric, channel->name, INSP_FORMAT("End of channel {} list.", name));
 }
 
 void ListModeBase::DisplayEmptyList(User* user, Channel* channel)
 {
-	user->WriteNumeric(endoflistnumeric, channel->name, InspIRCd::Format("Channel %s list is empty.", name.c_str()));
+	user->WriteNumeric(endoflistnumeric, channel->name, INSP_FORMAT("Channel {} list is empty.", name));
 }
 
 void ListModeBase::RemoveMode(Channel* channel, Modes::ChangeList& changelist)
@@ -82,7 +83,7 @@ void ListModeBase::DoRehash()
 		ListLimit limit(c->getString("chan", "*", 1), c->getUInt("limit", DEFAULT_LIST_SIZE));
 
 		if (limit.mask.empty())
-			throw ModuleException(creator, InspIRCd::Format("<maxlist:chan> is empty, at %s", c->source.str().c_str()));
+			throw ModuleException(creator, INSP_FORMAT("<maxlist:chan> is empty, at {}", c->source.str()));
 
 		if (limit.mask == "*" || limit.mask == "#*")
 			seen_default = true;
@@ -232,15 +233,15 @@ void ListModeBase::OnParameterMissing(User* source, User* dest, Channel* channel
 
 void ListModeBase::TellListTooLong(LocalUser* source, Channel* channel, const std::string& parameter)
 {
-	source->WriteNumeric(ERR_BANLISTFULL, channel->name, parameter, mode, InspIRCd::Format("Channel %s list is full", name.c_str()));
+	source->WriteNumeric(ERR_BANLISTFULL, channel->name, parameter, mode, INSP_FORMAT("Channel {} list is full", name));
 }
 
 void ListModeBase::TellAlreadyOnList(LocalUser* source, Channel* channel, const std::string& parameter)
 {
-	source->WriteNumeric(ERR_LISTMODEALREADYSET, channel->name, parameter, mode, InspIRCd::Format("Channel %s list already contains %s", name.c_str(), parameter.c_str()));
+	source->WriteNumeric(ERR_LISTMODEALREADYSET, channel->name, parameter, mode, INSP_FORMAT("Channel {} list already contains {}", name, parameter));
 }
 
 void ListModeBase::TellNotSet(LocalUser* source, Channel* channel, const std::string& parameter)
 {
-	source->WriteNumeric(ERR_LISTMODENOTSET, channel->name, parameter, mode, InspIRCd::Format("Channel %s list does not contain %s", name.c_str(), parameter.c_str()));
+	source->WriteNumeric(ERR_LISTMODENOTSET, channel->name, parameter, mode, INSP_FORMAT("Channel {} list does not contain {}", name, parameter));
 }
diff --git a/src/logging.cpp b/src/logging.cpp
index 13d6d3025..5b1806188 100644
--- a/src/logging.cpp
+++ b/src/logging.cpp
@@ -92,7 +92,7 @@ void Log::FileMethod::OnLog(time_t time, Level level, const std::string& type, c
 		fflush(file);
 
 	if (ferror(file))
-		throw CoreException(InspIRCd::Format("Unable to write to %s: %s", name.c_str(), strerror(errno)));
+		throw CoreException(INSP_FORMAT("Unable to write to {}: {}", name, strerror(errno)));
 }
 
 bool Log::FileMethod::Tick()
@@ -127,8 +127,8 @@ Log::MethodPtr Log::FileEngine::Create(const std::shared_ptr<ConfigTag>& tag)
 	auto* fh = fopen(fulltarget.c_str(), "a");
 	if (!fh)
 	{
-		throw CoreException(InspIRCd::Format("Unable to open %s for file logger at %s: %s",
-			fulltarget.c_str(), tag->source.str().c_str(), strerror(errno)));
+		throw CoreException(INSP_FORMAT("Unable to open {} for file logger at {}: {}", fulltarget,
+			tag->source.str(), strerror(errno)));
 	}
 
 	const unsigned long flush = tag->getUInt("flush", 20, 1);
diff --git a/src/mode.cpp b/src/mode.cpp
index 1012b2dbf..a10893a4c 100644
--- a/src/mode.cpp
+++ b/src/mode.cpp
@@ -87,9 +87,9 @@ void ModeHandler::DisplayEmptyList(User*, Channel*)
 
 void ModeHandler::OnParameterMissing(User* user, User* dest, Channel* channel)
 {
-	std::string message = InspIRCd::Format("You must specify a parameter for the %s mode.", name.c_str());
+	std::string message = INSP_FORMAT("You must specify a parameter for the {} mode.", name);
 	if (!syntax.empty())
-		message.append(InspIRCd::Format(" Syntax: %s.", syntax.c_str()));
+		message.append(INSP_FORMAT(" Syntax: {}.", syntax));
 
 	if (channel)
 		user->WriteNumeric(Numerics::InvalidModeParameter(channel, this, "*", message));
@@ -277,8 +277,8 @@ bool ModeParser::TryMode(User* user, User* targetuser, Channel* chan, Modes::Cha
 			ModeHandler::Rank ourrank = chan->GetPrefixValue(user);
 			if (ourrank < neededrank)
 			{
-				user->WriteNumeric(Numerics::ChannelPrivilegesNeeded(chan, neededrank, InspIRCd::Format("%s channel mode %c (%s)",
-					mcitem.adding ? "set" : "unset", mh->GetModeChar(), mh->name.c_str())));
+				user->WriteNumeric(Numerics::ChannelPrivilegesNeeded(chan, neededrank, INSP_FORMAT("{} channel mode {} ({})",
+					mcitem.adding ? "set" : "unset", mh->GetModeChar(), mh->name)));
 				return false;
 			}
 		}
@@ -303,13 +303,13 @@ bool ModeParser::TryMode(User* user, User* targetuser, Channel* chan, Modes::Cha
 		/* It's an oper only mode, and they don't have access to it. */
 		if (user->IsOper())
 		{
-			user->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - Oper type %s does not have access to %sset %s mode %c",
-				user->oper->GetType().c_str(), mcitem.adding ? "" : "un", type == MODETYPE_CHANNEL ? "channel" : "user", modechar));
+			user->WriteNumeric(ERR_NOPRIVILEGES, INSP_FORMAT("Permission Denied - Oper type {} does not have access to {} {} mode {}",
+				user->oper->GetType(), mcitem.adding ? "set" : "unset", type == MODETYPE_CHANNEL ? "channel" : "user", modechar));
 		}
 		else
 		{
-			user->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - Only operators may %sset %s mode %c",
-				mcitem.adding ? "" : "un", type == MODETYPE_CHANNEL ? "channel" : "user", modechar));
+			user->WriteNumeric(ERR_NOPRIVILEGES, INSP_FORMAT("Permission Denied - Only operators may {} {} mode {}",
+				mcitem.adding ? "set" : "unset", type == MODETYPE_CHANNEL ? "channel" : "user", modechar));
 		}
 		return false;
 	}
@@ -352,7 +352,7 @@ void ModeParser::ModeParamsToChangeList(User* user, ModeType type, const std::ve
 			/* No mode handler? Unknown mode character then. */
 			int numeric = (type == MODETYPE_CHANNEL ? ERR_UNKNOWNMODE : ERR_UNKNOWNSNOMASK);
 			const char* typestr = (type == MODETYPE_CHANNEL ? "channel" : "user");
-			user->WriteNumeric(numeric, modechar, InspIRCd::Format("is not a recognised %s mode.", typestr));
+			user->WriteNumeric(numeric, modechar, INSP_FORMAT("is not a recognised {} mode.", typestr));
 			continue;
 		}
 
@@ -560,10 +560,7 @@ ModeHandler::Id ModeParser::AllocateModeId(ModeHandler* mh)
 void ModeParser::AddMode(ModeHandler* mh)
 {
 	if (!ModeParser::IsModeChar(mh->GetModeChar()))
-	{
-		throw ModuleException(mh->creator, InspIRCd::Format("Mode letter for %s is invalid: %c",
-			mh->name.c_str(), mh->GetModeChar()));
-	}
+		throw ModuleException(mh->creator, INSP_FORMAT("Mode letter for {} is invalid: {}", mh->name, mh->GetModeChar()));
 
 	/* A mode prefix of ',' is not acceptable, it would fuck up server to server.
 	 * A mode prefix of ':' will fuck up both server to server, and client to server.
@@ -573,24 +570,21 @@ void ModeParser::AddMode(ModeHandler* mh)
 	if (pm)
 	{
 		if ((pm->GetPrefix() > 126) || (pm->GetPrefix() == ',') || (pm->GetPrefix() == ':') || ServerInstance->Channels.IsPrefix(pm->GetPrefix()))
-		{
-			throw ModuleException(mh->creator, InspIRCd::Format("Mode prefix for %s is invalid: %c",
-				mh->name.c_str(), pm->GetPrefix()));
-		}
+			throw ModuleException(mh->creator, INSP_FORMAT("Mode prefix for {} is invalid: {}", mh->name, pm->GetPrefix()));
 
 		PrefixMode* otherpm = FindPrefix(pm->GetPrefix());
 		if (otherpm)
 		{
-			throw ModuleException(mh->creator, InspIRCd::Format("Mode prefix for %s already used by %s from %s: %c",
-				mh->name.c_str(), otherpm->name.c_str(), otherpm->creator->ModuleSourceFile.c_str(), pm->GetPrefix()));
+			throw ModuleException(mh->creator, INSP_FORMAT("Mode prefix for {} already used by {} from {}: {}",
+				mh->name, otherpm->name, otherpm->creator->ModuleSourceFile, pm->GetPrefix()));
 		}
 	}
 
 	ModeHandler*& slot = modehandlers[mh->GetModeType()][ModeParser::GetModeIndex(mh->GetModeChar())];
 	if (slot)
 	{
-		throw ModuleException(mh->creator, InspIRCd::Format("Mode letter for %s already used by %s from %s: %c",
-			mh->name.c_str(), slot->name.c_str(), slot->creator->ModuleSourceFile.c_str(), mh->GetModeChar()));
+		throw ModuleException(mh->creator, INSP_FORMAT("Mode letter for {} already used by {} from {}: {}",
+			mh->name, slot->name, slot->creator->ModuleSourceFile, mh->GetModeChar()));
 	}
 
 	// The mode needs an id if it is either a user mode, a simple mode (flag) or a parameter mode.
@@ -603,8 +597,8 @@ void ModeParser::AddMode(ModeHandler* mh)
 	if (!res.second)
 	{
 		ModeHandler* othermh = res.first->second;
-		throw ModuleException(mh->creator, InspIRCd::Format("Mode name %s already used by %c from %s",
-			mh->name.c_str(), othermh->GetModeChar(), othermh->creator->ModuleSourceFile.c_str()));
+		throw ModuleException(mh->creator, INSP_FORMAT("Mode name {} already used by {} from {}",
+			mh->name, othermh->GetModeChar(), othermh->creator->ModuleSourceFile));
 	}
 
 	// Everything is fine, add the mode
diff --git a/src/modules/extra/m_geo_maxmind.cpp b/src/modules/extra/m_geo_maxmind.cpp
index cb9fc4761..65fd1e703 100644
--- a/src/modules/extra/m_geo_maxmind.cpp
+++ b/src/modules/extra/m_geo_maxmind.cpp
@@ -180,8 +180,8 @@ public:
 		MMDB_s mmdb;
 		int result = MMDB_open(file.c_str(), MMDB_MODE_MMAP, &mmdb);
 		if (result != MMDB_SUCCESS)
-			throw ModuleException(this, InspIRCd::Format("Unable to load the MaxMind database (%s): %s",
-				file.c_str(), MMDB_strerror(result)));
+			throw ModuleException(this, INSP_FORMAT("Unable to load the MaxMind database ({}): {}",
+				file, MMDB_strerror(result)));
 
 		// Swap the new database with the old database.
 		std::swap(mmdb, geoapi.mmdb);
diff --git a/src/modules/extra/m_ldap.cpp b/src/modules/extra/m_ldap.cpp
index 0a711131e..e3989e842 100644
--- a/src/modules/extra/m_ldap.cpp
+++ b/src/modules/extra/m_ldap.cpp
@@ -28,6 +28,7 @@
 /// $PackageInfo: require_system("debian") libldap2-dev
 /// $PackageInfo: require_system("ubuntu") libldap2-dev
 
+
 #include "inspircd.h"
 #include "threadsocket.h"
 #include "modules/ldap.h"
@@ -465,7 +466,7 @@ private:
 
 		if (res != req->success)
 		{
-			ldap_result->error = InspIRCd::Format("%s (%s)", ldap_err2string(res), req->info().c_str());
+			ldap_result->error = INSP_FORMAT("{} ({})", ldap_err2string(res), req->info());
 			return;
 		}
 
diff --git a/src/modules/extra/m_log_json.cpp b/src/modules/extra/m_log_json.cpp
index 567fa0ace..caa4add32 100644
--- a/src/modules/extra/m_log_json.cpp
+++ b/src/modules/extra/m_log_json.cpp
@@ -19,11 +19,11 @@
 /// $CompilerFlags: find_compiler_flags("RapidJSON")
 
 
-#include "inspircd.h"
-
 #include <rapidjson/ostreamwrapper.h>
 #include <rapidjson/writer.h>
 
+#include "inspircd.h"
+
 class JSONMethod final
 	: public Log::Method
 	, public Timer
@@ -106,7 +106,7 @@ public:
 			fflush(file);
 
 		if (ferror(file))
-			throw CoreException(InspIRCd::Format("Unable to write to %s: %s", name.c_str(), strerror(errno)));
+			throw CoreException(INSP_FORMAT("Unable to write to {}: {}", name, strerror(errno)));
 	}
 
 	// RapidJSON API: Write a character to the file.
@@ -141,8 +141,8 @@ public:
 		auto* fh = fopen(fulltarget.c_str(), "a");
 		if (!fh)
 		{
-			throw CoreException(InspIRCd::Format("Unable to open %s for JSON logger at %s: %s",
-				fulltarget.c_str(), tag->source.str().c_str(), strerror(errno)));
+			throw CoreException(INSP_FORMAT("Unable to open {} for JSON logger at {}: {}",
+				fulltarget, tag->source.str(), strerror(errno)));
 		}
 
 		const unsigned long flush = tag->getUInt("flush", 20, 1);
diff --git a/src/modules/extra/m_mysql.cpp b/src/modules/extra/m_mysql.cpp
index dca78a847..b676003a8 100644
--- a/src/modules/extra/m_mysql.cpp
+++ b/src/modules/extra/m_mysql.cpp
@@ -42,8 +42,8 @@
 #include <mysql_version.h>
 
 #include "inspircd.h"
-#include "threadsocket.h"
 #include "modules/sql.h"
+#include "threadsocket.h"
 
 #ifdef _WIN32
 # pragma comment(lib, "mysqlclient.lib")
@@ -288,7 +288,7 @@ private:
 		unsigned long escapedsize = mysql_escape_string(buffer.data(), in.c_str(), in.length());
 		if (escapedsize == static_cast<unsigned long>(-1))
 		{
-			SQL::Error err(SQL::QSEND_FAIL, InspIRCd::Format("%u: %s", mysql_errno(connection), mysql_error(connection)));
+			SQL::Error err(SQL::QSEND_FAIL, INSP_FORMAT("{}: {}", mysql_errno(connection), mysql_error(connection)));
 			query->OnError(err);
 			return false;
 		}
@@ -384,7 +384,7 @@ public:
 		{
 			/* XXX: See /usr/include/mysql/mysqld_error.h for a list of
 			 * possible error numbers and error messages */
-			SQL::Error e(SQL::QREPLY_FAIL, InspIRCd::Format("%u: %s", mysql_errno(connection), mysql_error(connection)));
+			SQL::Error e(SQL::QREPLY_FAIL, INSP_FORMAT("{}: {}", mysql_errno(connection), mysql_error(connection)));
 			return new MySQLresult(e);
 		}
 	}
diff --git a/src/modules/m_abbreviation.cpp b/src/modules/m_abbreviation.cpp
index 7cc0deb41..6e6f96d7b 100644
--- a/src/modules/m_abbreviation.cpp
+++ b/src/modules/m_abbreviation.cpp
@@ -78,7 +78,7 @@ public:
 		/* Ambiguous command, list the matches */
 		if (!matchlist.empty())
 		{
-			user->WriteNumeric(ERR_AMBIGUOUSCOMMAND, InspIRCd::Format("Ambiguous abbreviation, possible matches: %s%s", foundcommand.c_str(), matchlist.c_str()));
+			user->WriteNumeric(ERR_AMBIGUOUSCOMMAND, INSP_FORMAT("Ambiguous abbreviation, possible matches: {}{}", foundcommand, matchlist));
 			return MOD_RES_DENY;
 		}
 
diff --git a/src/modules/m_account.cpp b/src/modules/m_account.cpp
index 369ca9efb..a9850ba51 100644
--- a/src/modules/m_account.cpp
+++ b/src/modules/m_account.cpp
@@ -75,7 +75,7 @@ public:
 			else
 			{
 				// Logged in.
-				user->WriteNumeric(RPL_LOGGEDIN, user->GetFullHost(), value, InspIRCd::Format("You are now logged in as %s", value.c_str()));
+				user->WriteNumeric(RPL_LOGGEDIN, user->GetFullHost(), value, INSP_FORMAT("You are now logged in as {}", value));
 			}
 		}
 
diff --git a/src/modules/m_anticaps.cpp b/src/modules/m_anticaps.cpp
index b7a4d4caa..874ae07d3 100644
--- a/src/modules/m_anticaps.cpp
+++ b/src/modules/m_anticaps.cpp
@@ -270,8 +270,8 @@ public:
 		if (percent < config->percent)
 			return MOD_RES_PASSTHRU;
 
-		const std::string message = InspIRCd::Format("Your message exceeded the %d%% upper case character threshold for %s",
-			config->percent, channel->name.c_str());
+		const std::string message = INSP_FORMAT("Your message exceeded the {}% upper case character threshold for {}",
+			config->percent, channel->name);
 
 		switch (config->method)
 		{
diff --git a/src/modules/m_autoop.cpp b/src/modules/m_autoop.cpp
index d730a5caa..2815728d3 100644
--- a/src/modules/m_autoop.cpp
+++ b/src/modules/m_autoop.cpp
@@ -63,7 +63,7 @@ public:
 
 		if (change.adding && !mh)
 		{
-			source->WriteNumeric(ERR_UNKNOWNMODE, mid, InspIRCd::Format("Cannot find prefix mode '%s' for autoop", mid.c_str()));
+			source->WriteNumeric(ERR_UNKNOWNMODE, mid, INSP_FORMAT("Cannot find prefix mode '{}' for autoop", mid));
 			return MOD_RES_DENY;
 		}
 		else if (!mh)
@@ -75,8 +75,8 @@ public:
 
 		if (mh->GetLevelRequired(change.adding) > mylevel)
 		{
-			source->WriteNumeric(ERR_CHANOPRIVSNEEDED, channel->name, InspIRCd::Format("You must be able to %s mode %c (%s) to %s an autoop containing it",
-				change.adding ? "set" : "unset", mh->GetModeChar(), mh->name.c_str(), change.adding ? "add" : "remove"));
+			source->WriteNumeric(ERR_CHANOPRIVSNEEDED, channel->name, INSP_FORMAT("You must be able to {} mode {} ({}) to {} an autoop containing it",
+				change.adding ? "set" : "unset", mh->GetModeChar(), mh->name, change.adding ? "add" : "remove"));
 			return MOD_RES_DENY;
 		}
 		return MOD_RES_PASSTHRU;
diff --git a/src/modules/m_banredirect.cpp b/src/modules/m_banredirect.cpp
index a20fbe26f..7a8e4e8c0 100644
--- a/src/modules/m_banredirect.cpp
+++ b/src/modules/m_banredirect.cpp
@@ -96,7 +96,8 @@ public:
 			ListModeBase::ModeList* list = banlm->GetList(channel);
 			if (list && change.adding && maxbans <= list->size())
 			{
-				source->WriteNumeric(ERR_BANLISTFULL, channel->name, banlm->GetModeChar(), InspIRCd::Format("Channel ban list for %s is full (maximum entries for this channel is %lu)", channel->name.c_str(), maxbans));
+				source->WriteNumeric(ERR_BANLISTFULL, channel->name, banlm->GetModeChar(), INSP_FORMAT("Channel ban list for {} is full (maximum entries for this channel is {})",
+					channel->name, maxbans));
 				return false;
 			}
 
@@ -164,19 +165,19 @@ public:
 				{
 					if (!ServerInstance->Channels.IsChannel(mask[CHAN]))
 					{
-						source->WriteNumeric(ERR_NOSUCHCHANNEL, channel->name, InspIRCd::Format("Invalid channel name in redirection (%s)", mask[CHAN].c_str()));
+						source->WriteNumeric(ERR_NOSUCHCHANNEL, channel->name, INSP_FORMAT("Invalid channel name in redirection ({})", mask[CHAN]));
 						return false;
 					}
 
 					auto* c = ServerInstance->Channels.Find(mask[CHAN]);
 					if (!c)
 					{
-						source->WriteNumeric(690, InspIRCd::Format("Target channel %s must exist to be set as a redirect.", mask[CHAN].c_str()));
+						source->WriteNumeric(690, INSP_FORMAT("Target channel {} must exist to be set as a redirect.", mask[CHAN]));
 						return false;
 					}
 					else if (change.adding && c->GetPrefixValue(source) < OP_VALUE)
 					{
-						source->WriteNumeric(690, InspIRCd::Format("You must be opped on %s to set it as a redirect.", mask[CHAN].c_str()));
+						source->WriteNumeric(690, INSP_FORMAT("You must be opped on {} to set it as a redirect.", mask[CHAN]));
 						return false;
 					}
 
diff --git a/src/modules/m_callerid.cpp b/src/modules/m_callerid.cpp
index 4b392ae93..516d1d513 100644
--- a/src/modules/m_callerid.cpp
+++ b/src/modules/m_callerid.cpp
@@ -284,7 +284,7 @@ public:
 		callerid_data* dat = extInfo.Get(user, true);
 		if (dat->accepting.size() >= maxaccepts)
 		{
-			user->WriteNumeric(ERR_ACCEPTFULL, InspIRCd::Format("Accept list is full (limit is %lu)", maxaccepts));
+			user->WriteNumeric(ERR_ACCEPTFULL, INSP_FORMAT("Accept list is full (limit is {})", maxaccepts));
 			return false;
 		}
 		if (!dat->accepting.insert(whotoadd).second)
@@ -422,12 +422,14 @@ public:
 		{
 			time_t now = ServerInstance->Time();
 			/* +g and *not* accepted */
-			user->WriteNumeric(ERR_TARGUMODEG, dest->nick, InspIRCd::Format("is in +%c mode (server-side ignore).", myumode.GetModeChar()));
+			user->WriteNumeric(ERR_TARGUMODEG, dest->nick, INSP_FORMAT("is in +{} mode (server-side ignore).", myumode.GetModeChar()));
 			if (now > (dat->lastnotify + long(notify_cooldown)))
 			{
 				user->WriteNumeric(RPL_TARGNOTIFY, dest->nick, "has been informed that you messaged them.");
-				dest->WriteRemoteNumeric(RPL_UMODEGMSG, user->nick, InspIRCd::Format("%s@%s", user->ident.c_str(), user->GetDisplayedHost().c_str()), InspIRCd::Format("is messaging you, and you have user mode +%c set. Use /ACCEPT +%s to allow.",
-						myumode.GetModeChar(), user->nick.c_str()));
+				dest->WriteRemoteNumeric(RPL_UMODEGMSG, user->nick,
+					INSP_FORMAT("{}@{}", user->ident, user->GetDisplayedHost()),
+					INSP_FORMAT("is messaging you, and you have user mode +{} set. Use /ACCEPT +{} to allow.", myumode.GetModeChar(), user->nick)
+				);
 				dat->lastnotify = now;
 			}
 			return MOD_RES_DENY;
diff --git a/src/modules/m_cban.cpp b/src/modules/m_cban.cpp
index c797a13ce..74f884760 100644
--- a/src/modules/m_cban.cpp
+++ b/src/modules/m_cban.cpp
@@ -202,7 +202,7 @@ public:
 		if (rl)
 		{
 			// Channel is banned.
-			user->WriteNumeric(ERR_BADCHANNEL, cname, InspIRCd::Format("Channel %s is CBANed: %s", cname.c_str(), rl->reason.c_str()));
+			user->WriteNumeric(ERR_BADCHANNEL, cname, INSP_FORMAT("Channel {} is CBANed: {}", cname, rl->reason));
 			ServerInstance->SNO.WriteGlobalSno('a', "%s tried to join %s which is CBANed (%s)",
 				user->nick.c_str(), cname.c_str(), rl->reason.c_str());
 			return MOD_RES_DENY;
diff --git a/src/modules/m_chanfilter.cpp b/src/modules/m_chanfilter.cpp
index 759bc70de..722b90512 100644
--- a/src/modules/m_chanfilter.cpp
+++ b/src/modules/m_chanfilter.cpp
@@ -143,8 +143,10 @@ public:
 		if (hidemask)
 			user->WriteNumeric(Numerics::CannotSendTo(chan, "Your part message contained a banned phrase and was blocked."));
 		else
-			user->WriteNumeric(Numerics::CannotSendTo(chan, InspIRCd::Format("Your part message contained a banned phrase (%s) and was blocked.",
-				match->mask.c_str())));
+		{
+			user->WriteNumeric(Numerics::CannotSendTo(chan, INSP_FORMAT("Your part message contained a banned phrase ({}) and was blocked.",
+				match->mask)));
+		}
 	}
 
 	ModResult OnUserPreMessage(User* user, const MessageTarget& target, MessageDetails& details) override
@@ -165,8 +167,10 @@ public:
 			if (hidemask)
 				user->WriteNumeric(Numerics::CannotSendTo(chan, "Your message to this channel contained a banned phrase and was blocked."));
 			else
-				user->WriteNumeric(Numerics::CannotSendTo(chan, InspIRCd::Format("Your message to this channel contained a banned phrase (%s) and was blocked.",
-					match->mask.c_str())));
+			{
+				user->WriteNumeric(Numerics::CannotSendTo(chan, INSP_FORMAT("Your message to this channel contained a banned phrase ({}) and was blocked.",
+					match->mask)));
+			}
 
 			return MOD_RES_DENY;
 		}
diff --git a/src/modules/m_check.cpp b/src/modules/m_check.cpp
index bc7f1c253..110621510 100644
--- a/src/modules/m_check.cpp
+++ b/src/modules/m_check.cpp
@@ -243,9 +243,8 @@ public:
 				 * Unlike Asuka, I define a clone as coming from the same host. --w00t
 				 */
 				const UserManager::CloneCounts& clonecount = ServerInstance->Users.GetCloneCounts(u);
-				context.Write("member", InspIRCd::Format("%u %s%s (%s\x0F)", clonecount.global,
-					memb->GetAllPrefixChars().c_str(), u->GetFullHost().c_str(),
-					u->GetRealName().c_str()));
+				context.Write("member", INSP_FORMAT("{} {}{} ({}\x0F)", clonecount.global, memb->GetAllPrefixChars(),
+					u->GetFullHost(), u->GetRealName()));
 			}
 
 			for (auto* lm : ServerInstance->Modes.GetListModes())
@@ -285,9 +284,8 @@ public:
 				if (!matches.empty())
 				{
 					const std::string whatmatch = stdalgo::string::join(matches, ',');
-					context.Write("match", InspIRCd::Format("%ld %s %s %s %s %s %s :%s", ++x, whatmatch.c_str(),
-						u->nick.c_str(), u->ident.c_str(), u->GetRealHost().c_str(), u->GetDisplayedHost().c_str(),
-						u->GetIPString().c_str(), u->GetRealName().c_str()));
+					context.Write("match", INSP_FORMAT("{} {} {} {} {} {} {} :{}", ++x, whatmatch, u->nick, u->ident,
+						u->GetRealHost(), u->GetDisplayedHost(), u->GetIPString(), u->GetRealName()));
 					matches.clear();
 				}
 			}
diff --git a/src/modules/m_chghost.cpp b/src/modules/m_chghost.cpp
index b2a8b8b59..590bdb2d7 100644
--- a/src/modules/m_chghost.cpp
+++ b/src/modules/m_chghost.cpp
@@ -106,7 +106,7 @@ public:
 		{
 			// A hostname can not contain NUL, LF, CR, or SPACE.
 			if (chr == 0x00 || chr == 0x0A || chr == 0x0D || chr == 0x20)
-				throw ModuleException(this, InspIRCd::Format("<hostname:charmap> can not contain character 0x%02X (%c)", chr, chr));
+				throw ModuleException(this, INSP_FORMAT("<hostname:charmap> can not contain character 0x{:02X} ({})", chr, chr));
 			newhostmap.set(static_cast<unsigned char>(chr));
 		}
 		std::swap(newhostmap, cmd.hostmap);
diff --git a/src/modules/m_cloak.cpp b/src/modules/m_cloak.cpp
index 8c02ffc1e..2949601c4 100644
--- a/src/modules/m_cloak.cpp
+++ b/src/modules/m_cloak.cpp
@@ -62,14 +62,14 @@ public:
 			if (cloak.empty())
 				continue;
 
-			noterpl.SendIfCap(user, stdrplcap, this, "CLOAK_RESULT", parameters[0], cloak, InspIRCd::Format("Cloak #%zu for %s is %s (type: %s)",
-				++count, parameters[0].c_str(), cloak.c_str(), cloakmethod->GetName()));
+			noterpl.SendIfCap(user, stdrplcap, this, "CLOAK_RESULT", parameters[0], cloak, INSP_FORMAT("Cloak #{} for {} is {} (method: {})",
+				++count, parameters[0], cloak, cloakmethod->GetName()));
 		}
 
 		if (!count)
 		{
-			failrpl.SendIfCap(user, stdrplcap, this, "UNABLE_TO_CLOAK", parameters[0], InspIRCd::Format("There are no methods available for cloaking %s",
-				parameters[0].c_str()));
+			failrpl.SendIfCap(user, stdrplcap, this, "UNABLE_TO_CLOAK", parameters[0], INSP_FORMAT("There are no methods available for cloaking {}",
+				parameters[0]));
 		}
 
 		return CmdResult::SUCCESS;
diff --git a/src/modules/m_cloak_md5.cpp b/src/modules/m_cloak_md5.cpp
index 36e1e34d0..dc6f33613 100644
--- a/src/modules/m_cloak_md5.cpp
+++ b/src/modules/m_cloak_md5.cpp
@@ -169,14 +169,15 @@ struct CloakInfo final
 		{
 			if (ip.family() == AF_INET6)
 			{
-				rv.append(InspIRCd::Format(".%02x%02x.%02x%02x%s",
+				rv.append(INSP_FORMAT(".{:02x}{:02x}.{:02x}{:02x}{}",
 					ip.in6.sin6_addr.s6_addr[2], ip.in6.sin6_addr.s6_addr[3],
-					ip.in6.sin6_addr.s6_addr[0], ip.in6.sin6_addr.s6_addr[1], suffix.c_str()));
+					ip.in6.sin6_addr.s6_addr[0], ip.in6.sin6_addr.s6_addr[1],
+					suffix));
 			}
 			else
 			{
 				const unsigned char* ip4 = (const unsigned char*)&ip.in4.sin_addr;
-				rv.append(InspIRCd::Format(".%d.%d%s", ip4[1], ip4[0], suffix.c_str()));
+				rv.append(INSP_FORMAT(".{}.{}{}", ip4[1], ip4[0], suffix));
 			}
 		}
 		return rv;
diff --git a/src/modules/m_cloak_sha256.cpp b/src/modules/m_cloak_sha256.cpp
index 397b2f3bc..78deda345 100644
--- a/src/modules/m_cloak_sha256.cpp
+++ b/src/modules/m_cloak_sha256.cpp
@@ -109,11 +109,11 @@ private:
 		unsigned int c = (unsigned int)(address >> 16) & 0xFF;
 		unsigned int d = (unsigned int)(address >> 24) & 0xFF;
 
-		const std::string alpha = Hash(InspIRCd::Format("%u.%u.%u.%u", a, b, c, d));
-		const std::string beta  = Hash(InspIRCd::Format("%u.%u.%u", a, b, c));
-		const std::string gamma = Hash(InspIRCd::Format("%u.%u", a, b));
+		const std::string alpha = Hash(INSP_FORMAT("{}.{}.{}.{}", a, b, c, d));
+		const std::string beta  = Hash(INSP_FORMAT("{}.{}.{}", a, b, c));
+		const std::string gamma = Hash(INSP_FORMAT("{}.{}", a, b));
 
-		return Wrap(InspIRCd::Format("%s.%s.%s", alpha.c_str(), beta.c_str(), gamma.c_str()), suffix, '.');
+		return Wrap(INSP_FORMAT("{}.{}.{}", alpha, beta, gamma), suffix, '.');
 	}
 
 	std::string CloakIPv6(const unsigned char* address)
@@ -133,11 +133,11 @@ private:
 		unsigned int g = ntohs(address16[6]);
 		unsigned int h = ntohs(address16[7]);
 
-		const std::string alpha = Hash(InspIRCd::Format("%x:%x:%x:%x:%x:%x:%x:%x", a, b, c, d, e, f, g, h));
-		const std::string beta  = Hash(InspIRCd::Format("%x:%x:%x:%x:%x:%x:%x", a, b, c, d, e, f, g));
-		const std::string gamma = Hash(InspIRCd::Format("%x:%x:%x:%x", a, b, c, d));
+		const std::string alpha = Hash(INSP_FORMAT("{:x}:{:x}:{:x}:{:x}:{:x}:{:x}:{:x}:{:x}", a, b, c, d, e, f, g, h));
+		const std::string beta  = Hash(INSP_FORMAT("{:x}:{:x}:{:x}:{:x}:{:x}:{:x}:{:x}", a, b, c, d, e, f, g));
+		const std::string gamma = Hash(INSP_FORMAT("{:x}:{:x}:{:x}:{:x}", a, b, c, d));
 
-		return Wrap(InspIRCd::Format("%s:%s:%s", alpha.c_str(), beta.c_str(), gamma.c_str()), suffix, ':');
+		return Wrap(INSP_FORMAT("{}:{}:{}", alpha, beta, gamma), suffix, ':');
 	}
 
 	std::string CloakHost(const std::string& host, char separator, unsigned long parts)
diff --git a/src/modules/m_codepage.cpp b/src/modules/m_codepage.cpp
index 83ae5a79d..245e86849 100644
--- a/src/modules/m_codepage.cpp
+++ b/src/modules/m_codepage.cpp
@@ -154,8 +154,7 @@ public:
 			data["map"].push_back(',');
 		}
 
-		compatdata = InspIRCd::Format("front=%s&middle=%s&map=%s", data["front"].c_str(),
-			data["middle"].c_str(), data["map"].c_str());
+		compatdata = INSP_FORMAT("front={}&middle={}&map={}", data["front"], data["middle"], data["map"]);
 	}
 
 	bool Map(unsigned long upper, unsigned long lower) override
@@ -285,12 +284,12 @@ public:
 						break;
 
 					case Codepage::AllowCharacterResult::NOT_VALID:
-						throw ModuleException(this, InspIRCd::Format("<cpchars> tag contains a forbidden character: %lu at %s",
-							pos, tag->source.str().c_str()));
+						throw ModuleException(this, INSP_FORMAT("<cpchars> tag contains a forbidden character: {} at {}",
+							pos, tag->source.str()));
 
 					case Codepage::AllowCharacterResult::NOT_VALID_AT_FRONT:
-						throw ModuleException(this, InspIRCd::Format("<cpchars> tag contains a forbidden front character: %lu at %s",
-							pos, tag->source.str().c_str()));
+						throw ModuleException(this, INSP_FORMAT("<cpchars> tag contains a forbidden front character: {} at {}",
+							pos, tag->source.str()));
 				}
 			}
 		}
diff --git a/src/modules/m_dccallow.cpp b/src/modules/m_dccallow.cpp
index b346c8641..b0dce6c2a 100644
--- a/src/modules/m_dccallow.cpp
+++ b/src/modules/m_dccallow.cpp
@@ -258,7 +258,7 @@ public:
 							if (i->nickname == target->nick)
 							{
 								dl->erase(i);
-								user->WriteNumeric(RPL_DCCALLOWREMOVED, user->nick, InspIRCd::Format("Removed %s from your DCCALLOW list", target->nick.c_str()));
+								user->WriteNumeric(RPL_DCCALLOWREMOVED, user->nick, INSP_FORMAT("Removed {} from your DCCALLOW list", target->nick));
 								break;
 							}
 						}
@@ -291,7 +291,7 @@ public:
 					{
 						if (dccallow.nickname == target->nick)
 						{
-							user->WriteNumeric(ERR_DCCALLOWINVALID, user->nick, InspIRCd::Format("%s is already on your DCCALLOW list", target->nick.c_str()));
+							user->WriteNumeric(ERR_DCCALLOWINVALID, user->nick, INSP_FORMAT("{} is already on your DCCALLOW list", target->nick));
 							return CmdResult::FAILURE;
 						}
 					}
@@ -304,7 +304,7 @@ public:
 					}
 					else if (!Duration::IsValid(parameters[1]))
 					{
-						user->WriteNumeric(ERR_DCCALLOWINVALID, user->nick, InspIRCd::Format("%s is not a valid DCCALLOW duration", parameters[1].c_str()));
+						user->WriteNumeric(ERR_DCCALLOWINVALID, user->nick, INSP_FORMAT("{} is not a valid DCCALLOW duration", parameters[1]));
 						return CmdResult::FAILURE;
 					}
 					else
@@ -325,11 +325,11 @@ public:
 
 					if (length > 0)
 					{
-						user->WriteNumeric(RPL_DCCALLOWTIMED, user->nick, InspIRCd::Format("Added %s to DCCALLOW list for %s", target->nick.c_str(), Duration::ToString(length).c_str()));
+						user->WriteNumeric(RPL_DCCALLOWTIMED, user->nick, INSP_FORMAT("Added {} to DCCALLOW list for {}", target->nick, Duration::ToString(length)));
 					}
 					else
 					{
-						user->WriteNumeric(RPL_DCCALLOWPERMANENT, user->nick, InspIRCd::Format("Added %s to DCCALLOW list for this session", target->nick.c_str()));
+						user->WriteNumeric(RPL_DCCALLOWPERMANENT, user->nick, INSP_FORMAT("Added {} to DCCALLOW list for this session", target->nick));
 					}
 
 					/* route it. */
@@ -373,8 +373,8 @@ public:
 		{
 			for (const auto& dccallow : *dl)
 			{
-				user->WriteNumeric(RPL_DCCALLOWLIST, user->nick, InspIRCd::Format("%s (%s)",
-					dccallow.nickname.c_str(), dccallow.hostmask.c_str()));
+				user->WriteNumeric(RPL_DCCALLOWLIST, user->nick, INSP_FORMAT("{} ({})",
+					dccallow.nickname, dccallow.hostmask));
 			}
 		}
 
@@ -539,7 +539,7 @@ public:
 						time_t expires = iter2->set_on + iter2->length;
 						if (iter2->length != 0 && expires <= ServerInstance->Time())
 						{
-							u->WriteNumeric(RPL_DCCALLOWEXPIRED, u->nick, InspIRCd::Format("DCCALLOW entry for %s has expired", iter2->nickname.c_str()));
+							u->WriteNumeric(RPL_DCCALLOWEXPIRED, u->nick, INSP_FORMAT("DCCALLOW entry for {} has expired", iter2->nickname));
 							iter2 = dl->erase(iter2);
 						}
 						else
@@ -574,7 +574,7 @@ public:
 						{
 
 							u->WriteNotice(i->nickname + " left the network or changed their nickname and has been removed from your DCCALLOW list");
-							u->WriteNumeric(RPL_DCCALLOWREMOVED, u->nick, InspIRCd::Format("Removed %s from your DCCALLOW list", i->nickname.c_str()));
+							u->WriteNumeric(RPL_DCCALLOWREMOVED, u->nick, INSP_FORMAT("Removed {} from your DCCALLOW list", i->nickname));
 							dl->erase(i);
 							break;
 						}
diff --git a/src/modules/m_delaymsg.cpp b/src/modules/m_delaymsg.cpp
index 25d744656..97c2f22e0 100644
--- a/src/modules/m_delaymsg.cpp
+++ b/src/modules/m_delaymsg.cpp
@@ -143,7 +143,7 @@ ModResult ModuleDelayMsg::HandleMessage(User* user, const MessageTarget& target,
 		if (user->HasPrivPermission("channels/ignore-delaymsg"))
 			return MOD_RES_PASSTHRU;
 
-		const std::string message = InspIRCd::Format("You cannot send messages to this channel until you have been a member for %ld seconds.", len);
+		const std::string message = INSP_FORMAT("You cannot send messages to this channel until you have been a member for {} seconds.", len);
 		user->WriteNumeric(Numerics::CannotSendTo(channel, message));
 		return MOD_RES_DENY;
 	}
diff --git a/src/modules/m_denychans.cpp b/src/modules/m_denychans.cpp
index 7f64a3289..c1d1b4a54 100644
--- a/src/modules/m_denychans.cpp
+++ b/src/modules/m_denychans.cpp
@@ -171,14 +171,14 @@ public:
 			if (badchan.redirect.empty() || user->IsModeSet(antiredirectmode)
 				|| ((target = ServerInstance->Channels.Find(badchan.redirect)) && target->IsModeSet(redirectmode)))
 			{
-				user->WriteNumeric(ERR_BADCHANNEL, cname, InspIRCd::Format("Channel %s is forbidden: %s",
-					cname.c_str(), badchan.reason.c_str()));
+				user->WriteNumeric(ERR_BADCHANNEL, cname, INSP_FORMAT("Channel {} is forbidden: {}", cname,
+					badchan.reason));
 				return MOD_RES_DENY;
 			}
 
 			// Redirect the user to the target channel.
-			user->WriteNumeric(ERR_BADCHANNEL, cname, InspIRCd::Format("Channel %s is forbidden, redirecting to %s: %s",
-				cname.c_str(), badchan.redirect.c_str(), badchan.reason.c_str()));
+			user->WriteNumeric(ERR_BADCHANNEL, cname, INSP_FORMAT("Channel {} is forbidden, redirecting to {}: {}",
+				cname, badchan.redirect, badchan.reason));
 			Channel::JoinUser(user, badchan.redirect);
 			return MOD_RES_DENY;
 		}
diff --git a/src/modules/m_disable.cpp b/src/modules/m_disable.cpp
index a264642ec..b7bc31892 100644
--- a/src/modules/m_disable.cpp
+++ b/src/modules/m_disable.cpp
@@ -48,14 +48,14 @@ private:
 		{
 			// Check that the character is a valid mode letter.
 			if (!ModeParser::IsModeChar(chr))
-				throw ModuleException(this, InspIRCd::Format("Invalid mode '%c' was specified in <disabled:%s> at %s",
-					chr, field.c_str(), tag->source.str().c_str()));
+				throw ModuleException(this, INSP_FORMAT("Invalid mode '{}' was specified in <disabled:{}> at {}",
+					chr, field, tag->source.str()));
 
 			// Check that the mode actually exists.
 			ModeHandler* mh = ServerInstance->Modes.FindMode(chr, type);
 			if (!mh)
-				throw ModuleException(this, InspIRCd::Format("Nonexistent mode '%c' was specified in <disabled:%s> at %s",
-					chr, field.c_str(), tag->source.str().c_str()));
+				throw ModuleException(this, INSP_FORMAT("Nonexistent mode '{}' was specified in <disabled:{}> at {}",
+					chr, field, tag->source.str()));
 
 			// Disable the mode.
 			ServerInstance->Logs.Debug(MODNAME, "The %c (%s) %s mode has been disabled",
@@ -93,8 +93,8 @@ public:
 			// Check that the command actually exists.
 			Command* handler = ServerInstance->Parser.GetHandler(command);
 			if (!handler)
-				throw ModuleException(this, InspIRCd::Format("Nonexistent command '%s' was specified in <disabled:commands> at %s",
-					command.c_str(), tag->source.str().c_str()));
+				throw ModuleException(this, INSP_FORMAT("Nonexistent command '{}' was specified in <disabled:commands> at {}",
+					command, tag->source.str()));
 
 			// Prevent admins from disabling MODULES for transparency reasons.
 			if (handler->name == "MODULES")
@@ -190,13 +190,13 @@ public:
 			// treated as if they do not exist.
 			int numeric = (change.mh->GetModeType() == MODETYPE_CHANNEL ? ERR_UNKNOWNMODE : ERR_UNKNOWNSNOMASK);
 			const char* typestr = (change.mh->GetModeType() == MODETYPE_CHANNEL ? "channel" : "user");
-			user->WriteNumeric(numeric, change.mh->GetModeChar(), InspIRCd::Format("is not a recognised %s mode.", typestr));
+			user->WriteNumeric(numeric, change.mh->GetModeChar(), INSP_FORMAT("is not a recognised {} mode.", typestr));
 			return MOD_RES_DENY;
 		}
 
 		// Inform the user that the mode they changed has been disabled.
-		user->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - %s mode %c (%s) is disabled",
-			what, change.mh->GetModeChar(), change.mh->name.c_str()));
+		user->WriteNumeric(ERR_NOPRIVILEGES, INSP_FORMAT("Permission Denied - {} mode {} ({}) is disabled",
+			what, change.mh->GetModeChar(), change.mh->name));
 		return MOD_RES_DENY;
 	}
 };
diff --git a/src/modules/m_dnsbl.cpp b/src/modules/m_dnsbl.cpp
index e7e16ba65..f28c277c6 100644
--- a/src/modules/m_dnsbl.cpp
+++ b/src/modules/m_dnsbl.cpp
@@ -572,8 +572,8 @@ public:
 			total_misses += dnsbl->stats_misses;
 			total_errors += dnsbl->stats_errors;
 
-			stats.AddGenericRow(InspIRCd::Format("The \"%s\" DNSBL had %lu hits, %lu misses, and %lu errors",
-				dnsbl->name.c_str(), dnsbl->stats_hits, dnsbl->stats_misses, dnsbl->stats_errors));
+			stats.AddGenericRow(INSP_FORMAT("The \"{}\" DNSBL had {} hits, {} misses, and {} errors",
+				dnsbl->name, dnsbl->stats_hits, dnsbl->stats_misses, dnsbl->stats_errors));
 		}
 
 		stats.AddGenericRow("Total DNSBL hits: " + ConvToStr(total_hits));
diff --git a/src/modules/m_exemptchanops.cpp b/src/modules/m_exemptchanops.cpp
index c08144f91..6df211a55 100644
--- a/src/modules/m_exemptchanops.cpp
+++ b/src/modules/m_exemptchanops.cpp
@@ -76,8 +76,8 @@ public:
 		if (channel->GetPrefixValue(source) >= pm->GetLevelRequired(change.adding))
 			return MOD_RES_PASSTHRU;
 
-		source->WriteNumeric(ERR_CHANOPRIVSNEEDED, channel->name, InspIRCd::Format("You must be able to %s mode %c (%s) to %s a restriction containing it",
-			change.adding ? "set" : "unset", pm->GetModeChar(), pm->name.c_str(), change.adding ? "add" : "remove"));
+		source->WriteNumeric(ERR_CHANOPRIVSNEEDED, channel->name, INSP_FORMAT("You must be able to {} mode {} ({}) to {} a restriction containing it",
+			change.adding ? "set" : "unset", pm->GetModeChar(), pm->name, change.adding ? "add" : "remove"));
 		return MOD_RES_DENY;
 	}
 
diff --git a/src/modules/m_filter.cpp b/src/modules/m_filter.cpp
index 70acc5099..4248b83f9 100644
--- a/src/modules/m_filter.cpp
+++ b/src/modules/m_filter.cpp
@@ -311,11 +311,9 @@ CmdResult CommandFilter::Handle(User* user, const Params& parameters)
 			std::pair<bool, std::string> result = static_cast<ModuleFilter*>(me)->AddFilter(freeform, type, parameters[reasonindex], duration, flags);
 			if (result.first)
 			{
-				const std::string message = InspIRCd::Format("'%s', type '%s'%s, flags '%s', reason: %s",
-					freeform.c_str(), parameters[1].c_str(),
-					(duration ? InspIRCd::Format(", duration '%s'",
-						Duration::ToString(duration).c_str()).c_str()
-					: ""), flags.c_str(), parameters[reasonindex].c_str());
+				const std::string message = INSP_FORMAT("'{}', type '{}'{}, flags '{}', reason: {}", freeform, parameters[1],
+					(duration ? INSP_FORMAT(", duration '{}'", Duration::ToString(duration)) : ""),
+					flags, parameters[reasonindex]);
 
 				user->WriteNotice("*** Added filter " + message);
 				ServerInstance->SNO.WriteToSnoMask(IS_LOCAL(user) ? 'f' : 'F',
@@ -422,26 +420,26 @@ ModResult ModuleFilter::OnUserPreMessage(User* user, const MessageTarget& msgtar
 
 		if (is_selfmsg && warnonselfmsg)
 		{
-			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("WARNING: %s's self message matched %s (%s)",
-				user->nick.c_str(), f->freeform.c_str(), f->reason.c_str()));
+			ServerInstance->SNO.WriteGlobalSno('f', "WARNING: %s's self message matched %s (%s)",
+				user->nick.c_str(), f->freeform.c_str(), f->reason.c_str());
 			return MOD_RES_PASSTHRU;
 		}
 		else if (f->action == FA_WARN)
 		{
-			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("WARNING: %s's message to %s matched %s (%s)",
-				user->nick.c_str(), msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str()));
+			ServerInstance->SNO.WriteGlobalSno('f', "WARNING: %s's message to %s matched %s (%s)",
+				user->nick.c_str(), msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str());
 			return MOD_RES_PASSTHRU;
 		}
 		else if (f->action == FA_BLOCK)
 		{
-			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s had their message to %s filtered as it matched %s (%s)",
-				user->nick.c_str(), msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str()));
+			ServerInstance->SNO.WriteGlobalSno('f', "%s had their message to %s filtered as it matched %s (%s)",
+				user->nick.c_str(), msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str());
 			if (notifyuser)
 			{
 				if (msgtarget.type == MessageTarget::TYPE_CHANNEL)
-					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<Channel>(), InspIRCd::Format("Your message to this channel was blocked: %s.", f->reason.c_str())));
+					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<Channel>(), INSP_FORMAT("Your message to this channel was blocked: {}.", f->reason)));
 				else
-					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<User>(), InspIRCd::Format("Your message to this user was blocked: %s.", f->reason.c_str())));
+					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<User>(), INSP_FORMAT("Your message to this user was blocked: {}.", f->reason)));
 			}
 			else
 				details.echo_original = true;
@@ -451,26 +449,26 @@ ModResult ModuleFilter::OnUserPreMessage(User* user, const MessageTarget& msgtar
 			if (notifyuser)
 			{
 				if (msgtarget.type == MessageTarget::TYPE_CHANNEL)
-					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<Channel>(), InspIRCd::Format("Your message to this channel was blocked: %s.", f->reason.c_str())));
+					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<Channel>(), INSP_FORMAT("Your message to this channel was blocked: {}.", f->reason)));
 				else
-					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<User>(), InspIRCd::Format("Your message to this user was blocked: %s.", f->reason.c_str())));
+					user->WriteNumeric(Numerics::CannotSendTo(msgtarget.Get<User>(), INSP_FORMAT("Your message to this user was blocked: {}.", f->reason)));
 			}
 			else
 				details.echo_original = true;
 		}
 		else if (f->action == FA_KILL)
 		{
-			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s was killed because their message to %s matched %s (%s)",
-				user->nick.c_str(), msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str()));
+			ServerInstance->SNO.WriteGlobalSno('f', "%s was killed because their message to %s matched %s (%s)",
+				user->nick.c_str(), msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str());
 			ServerInstance->Users.QuitUser(user, "Filtered: " + f->reason);
 		}
 		else if (f->action == FA_SHUN && (ServerInstance->XLines->GetFactory("SHUN")))
 		{
 			auto* sh = new Shun(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
-			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was shunned for %s (expires on %s) because their message to %s matched %s (%s)",
+			ServerInstance->SNO.WriteGlobalSno('f', "%s (%s) was shunned for %s (expires on %s) because their message to %s matched %s (%s)",
 				user->nick.c_str(), sh->Displayable().c_str(), Duration::ToString(f->duration).c_str(),
 				InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
-				msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str()));
+				msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str());
 			if (ServerInstance->XLines->AddLine(sh, nullptr))
 			{
 				ServerInstance->XLines->ApplyLines();
@@ -481,10 +479,10 @@ ModResult ModuleFilter::OnUserPreMessage(User* user, const MessageTarget& msgtar
 		else if (f->action == FA_GLINE)
 		{
 			auto* gl = new GLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, "*", user->GetIPString());
-			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was G-lined for %s (expires on %s) because their message to %s matched %s (%s)",
+			ServerInstance->SNO.WriteGlobalSno('f', "%s (%s) was G-lined for %s (expires on %s) because their message to %s matched %s (%s)",
 				user->nick.c_str(), gl->Displayable().c_str(), Duration::ToString(f->duration).c_str(),
 				InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
-				msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str()));
+				msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str());
 			if (ServerInstance->XLines->AddLine(gl, nullptr))
 			{
 				ServerInstance->XLines->ApplyLines();
@@ -495,10 +493,10 @@ ModResult ModuleFilter::OnUserPreMessage(User* user, const MessageTarget& msgtar
 		else if (f->action == FA_ZLINE)
 		{
 			auto* zl = new ZLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
-			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was Z-lined for %s (expires on %s) because their message to %s matched %s (%s)",
+			ServerInstance->SNO.WriteGlobalSno('f', "%s (%s) was Z-lined for %s (expires on %s) because their message to %s matched %s (%s)",
 				user->nick.c_str(), zl->Displayable().c_str(), Duration::ToString(f->duration).c_str(),
 				InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
-				msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str()));
+				msgtarget.GetName().c_str(), f->freeform.c_str(), f->reason.c_str());
 			if (ServerInstance->XLines->AddLine(zl, nullptr))
 			{
 				ServerInstance->XLines->ApplyLines();
@@ -572,11 +570,11 @@ ModResult ModuleFilter::OnPreCommand(std::string& command, CommandBase::Params&
 			{
 				/* Note: We G-line *@IP so that if their host doesn't resolve the G-line still applies. */
 				auto* gl = new GLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, "*", user->GetIPString());
-				ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was G-lined for %s (expires on %s) because their %s message matched %s (%s)",
+				ServerInstance->SNO.WriteGlobalSno('f', "%s (%s) was G-lined for %s (expires on %s) because their %s message matched %s (%s)",
 					user->nick.c_str(), gl->Displayable().c_str(),
 					Duration::ToString(f->duration).c_str(),
 					InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
-					command.c_str(), f->freeform.c_str(), f->reason.c_str()));
+					command.c_str(), f->freeform.c_str(), f->reason.c_str());
 
 				if (ServerInstance->XLines->AddLine(gl, nullptr))
 				{
@@ -588,11 +586,11 @@ ModResult ModuleFilter::OnPreCommand(std::string& command, CommandBase::Params&
 			if (f->action == FA_ZLINE)
 			{
 				auto* zl = new ZLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
-				ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was Z-lined for %s (expires on %s) because their %s message matched %s (%s)",
+				ServerInstance->SNO.WriteGlobalSno('f', "%s (%s) was Z-lined for %s (expires on %s) because their %s message matched %s (%s)",
 					user->nick.c_str(), zl->Displayable().c_str(),
 					Duration::ToString(f->duration).c_str(),
 					InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
-					command.c_str(), f->freeform.c_str(), f->reason.c_str()));
+					command.c_str(), f->freeform.c_str(), f->reason.c_str());
 
 				if (ServerInstance->XLines->AddLine(zl, nullptr))
 				{
@@ -605,11 +603,11 @@ ModResult ModuleFilter::OnPreCommand(std::string& command, CommandBase::Params&
 			{
 				/* Note: We shun *!*@IP so that if their host doesnt resolve the shun still applies. */
 				auto* sh = new Shun(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
-				ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was shunned for %s (expires on %s) because their %s message matched %s (%s)",
+				ServerInstance->SNO.WriteGlobalSno('f', "%s (%s) was shunned for %s (expires on %s) because their %s message matched %s (%s)",
 					user->nick.c_str(), sh->Displayable().c_str(),
 					Duration::ToString(f->duration).c_str(),
 					InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
-					command.c_str(), f->freeform.c_str(), f->reason.c_str()));
+					command.c_str(), f->freeform.c_str(), f->reason.c_str());
 
 				if (ServerInstance->XLines->AddLine(sh, nullptr))
 				{
diff --git a/src/modules/m_gateway.cpp b/src/modules/m_gateway.cpp
index a68ea5a07..bb6b23abe 100644
--- a/src/modules/m_gateway.cpp
+++ b/src/modules/m_gateway.cpp
@@ -150,21 +150,20 @@ public:
 			}
 
 			uint32_t addr = sa.in4.sin_addr.s_addr;
-			user->WriteNotice(InspIRCd::Format("*** HEXIP: %s encodes to %02x%02x%02x%02x.",
-				sa.addr().c_str(), (addr & 0xFF), ((addr >> 8) & 0xFF), ((addr >> 16) & 0xFF),
+			user->WriteNotice(INSP_FORMAT("*** HEXIP: {} encodes to {:02x}{:02x}{:02x}{:02x}.",
+				sa.addr(), (addr & 0xFF), ((addr >> 8) & 0xFF), ((addr >> 16) & 0xFF),
 				((addr >> 24) & 0xFF)));
 			return CmdResult::SUCCESS;
 		}
 
 		if (ParseIP(parameters[0], sa))
 		{
-			user->WriteNotice(InspIRCd::Format("*** HEXIP: %s decodes to %s.",
-				parameters[0].c_str(), sa.addr().c_str()));
+			user->WriteNotice(INSP_FORMAT("*** HEXIP: {} decodes to {}.", parameters[0], sa.addr()));
 			return CmdResult::SUCCESS;
 		}
 
-		user->WriteNotice(InspIRCd::Format("*** HEXIP: %s is not a valid raw or hex encoded IPv4 address.",
-			parameters[0].c_str()));
+		user->WriteNotice(INSP_FORMAT("*** HEXIP: {} is not a valid raw or hex encoded IPv4 address.",
+			parameters[0]));
 		return CmdResult::FAILURE;
 	}
 
diff --git a/src/modules/m_geoclass.cpp b/src/modules/m_geoclass.cpp
index c57073cc5..386aa31c4 100644
--- a/src/modules/m_geoclass.cpp
+++ b/src/modules/m_geoclass.cpp
@@ -85,12 +85,12 @@ public:
 
 		for (const auto& [location, count] : counts)
 		{
-			stats.AddGenericRow(InspIRCd::Format("%s (%s): %lu", location->GetName().c_str(),
-				location->GetCode().c_str(), count));
+			stats.AddGenericRow(INSP_FORMAT("{} ({}): {}", location->GetName(),
+				location->GetCode(), count));
 		}
 
 		if (unknown)
-			stats.AddGenericRow("Unknown Country: " + ConvToStr(unknown));
+			stats.AddGenericRow(INSP_FORMAT("Unknown Country: {}", unknown));
 
 		return MOD_RES_DENY;
 	}
diff --git a/src/modules/m_helpop.cpp b/src/modules/m_helpop.cpp
index 861347fa3..5fe3026ca 100644
--- a/src/modules/m_helpop.cpp
+++ b/src/modules/m_helpop.cpp
@@ -121,16 +121,16 @@ public:
 			// Attempt to read the help key.
 			const std::string key = tag->getString("key");
 			if (key.empty())
-				throw ModuleException(this, InspIRCd::Format("<helpop:key> is empty at %s", tag->source.str().c_str()));
+				throw ModuleException(this, INSP_FORMAT("<helpop:key> is empty at {}", tag->source.str()));
 			else if (irc::equals(key, "index"))
-				throw ModuleException(this, InspIRCd::Format("<helpop:key> is set to \"index\" which is reserved at %s", tag->source.str().c_str()));
+				throw ModuleException(this, INSP_FORMAT("<helpop:key> is set to \"index\" which is reserved at {}", tag->source.str()));
 			else if (key.length() > longestkey)
 				longestkey = key.length();
 
 			// Attempt to read the help value.
 			std::string value;
 			if (!tag->readString("value", value, true) || value.empty())
-				throw ModuleException(this, InspIRCd::Format("<helpop:value> is empty at %s", tag->source.str().c_str()));
+				throw ModuleException(this, INSP_FORMAT("<helpop:value> is empty at {}", tag->source.str()));
 
 			// Parse the help body. Empty lines are replaced with a single
 			// space because some clients are unable to show blank lines.
@@ -140,11 +140,11 @@ public:
 				helpmsg.push_back(line.empty() ? " " : line);
 
 			// Read the help title and store the topic.
-			const std::string title = tag->getString("title", InspIRCd::Format("*** Help for %s", key.c_str()), 1);
+			const std::string title = tag->getString("title", INSP_FORMAT("*** Help for {}", key), 1);
 			if (!newhelp.emplace(key, HelpTopic(helpmsg, title)).second)
 			{
-				throw ModuleException(this, InspIRCd::Format("<helpop> tag with duplicate key '%s' at %s",
-					key.c_str(), tag->source.str().c_str()));
+				throw ModuleException(this, INSP_FORMAT("<helpop> tag with duplicate key '{}' at {}",
+					key, tag->source.str()));
 			}
 		}
 
diff --git a/src/modules/m_hidelist.cpp b/src/modules/m_hidelist.cpp
index 8dec3855d..ba3cc0ae1 100644
--- a/src/modules/m_hidelist.cpp
+++ b/src/modules/m_hidelist.cpp
@@ -50,7 +50,7 @@ public:
 		if (user->HasPrivPermission("channels/auspex"))
 			return true;
 
-		user->WriteNumeric(Numerics::ChannelPrivilegesNeeded(chan, minrank, InspIRCd::Format("view the channel %s list", GetModeName().c_str())));
+		user->WriteNumeric(Numerics::ChannelPrivilegesNeeded(chan, minrank, INSP_FORMAT("view the channel {} list", GetModeName())));
 		return false;
 	}
 };
diff --git a/src/modules/m_hideoper.cpp b/src/modules/m_hideoper.cpp
index b0cc76005..6970ab2ce 100644
--- a/src/modules/m_hideoper.cpp
+++ b/src/modules/m_hideoper.cpp
@@ -161,8 +161,8 @@ public:
 			{
 				const std::string awayperiod = Duration::ToString(ServerInstance->Time() - oper->awaytime);
 				const std::string awaytime = InspIRCd::TimeString(oper->awaytime);
-				extra += InspIRCd::Format(": away for %s [since %s] (%s)", awayperiod.c_str(),
-					awaytime.c_str(), oper->awaymsg.c_str());
+
+				extra = INSP_FORMAT(": away for {} [since {}] ({})", awayperiod, awaytime, oper->awaymsg);
 			}
 
 			auto* loper = IS_LOCAL(oper);
@@ -170,14 +170,13 @@ public:
 			{
 				const std::string idleperiod = Duration::ToString(ServerInstance->Time() - loper->idle_lastmsg);
 				const std::string idletime = InspIRCd::TimeString(loper->idle_lastmsg);
-				extra += InspIRCd::Format("%c idle for %s [since %s]",  extra.empty() ? ':' : ',',
-					idleperiod.c_str(), idletime.c_str());
+
+				extra += INSP_FORMAT("{} idle for {} [since {}]", extra.empty() ? ':' : ',', idleperiod, idletime);
 			}
 
-			stats.AddGenericRow(InspIRCd::Format("\x02%s\x02 (%s)%s", oper->nick.c_str(),
-				oper->MakeHost().c_str(), extra.c_str()));
+			stats.AddGenericRow(INSP_FORMAT("\x02{}\x02 ({}){}", oper->nick, oper->MakeHost(), extra));
 		}
-		stats.AddGenericRow(InspIRCd::Format("%zu server operator%s total", opers, opers ? "s" : ""));
+		stats.AddGenericRow(INSP_FORMAT("{} server operator{} total", opers, opers ? "s" : ""));
 		return MOD_RES_DENY;
 	}
 };
diff --git a/src/modules/m_hostchange.cpp b/src/modules/m_hostchange.cpp
index 22df16eee..be2956c73 100644
--- a/src/modules/m_hostchange.cpp
+++ b/src/modules/m_hostchange.cpp
@@ -201,7 +201,7 @@ public:
 		{
 			// A hostname can not contain NUL, LF, CR, or SPACE.
 			if (chr == 0x00 || chr == 0x0A || chr == 0x0D || chr == 0x20)
-				throw ModuleException(this, InspIRCd::Format("<hostname:charmap> can not contain character 0x%02X (%c)", chr, chr));
+				throw ModuleException(this, INSP_FORMAT("<hostname:charmap> can not contain character 0x{:02X} ({})", chr, chr));
 			newhostmap.set(static_cast<unsigned char>(chr));
 		}
 		std::swap(newhostmap, hostmap);
diff --git a/src/modules/m_httpd.cpp b/src/modules/m_httpd.cpp
index 29c6ff41e..72af19738 100644
--- a/src/modules/m_httpd.cpp
+++ b/src/modules/m_httpd.cpp
@@ -256,9 +256,9 @@ public:
 
 		ServerInstance->Logs.Debug(MODNAME, "Sending HTTP error %u: %s", response, errstr);
 		static HTTPHeaders empty;
-		std::string data = InspIRCd::Format(
+		std::string data = INSP_FORMAT(
 			"<html><head></head><body style='font-family: sans-serif; text-align: center'>"
-			"<h1 style='font-size: 48pt'>Error %u</h1><h2 style='font-size: 24pt'>%s</h2><hr>"
+			"<h1 style='font-size: 48pt'>Error {}</h1><h2 style='font-size: 24pt'>{}</h2><hr>"
 			"<small>Powered by <a href='https://www.inspircd.org'>InspIRCd</a></small></body></html>",
 			response, errstr);
 
@@ -267,7 +267,7 @@ public:
 
 	void SendHeaders(unsigned long size, unsigned int response, HTTPHeaders& rheaders)
 	{
-		WriteData(InspIRCd::Format("HTTP/%u.%u %u %s\r\n", parser.http_major ? parser.http_major : 1, parser.http_major ? parser.http_minor : 1, response, http_status_str((http_status)response)));
+		WriteData(INSP_FORMAT("HTTP/{}.{} {} {}\r\n", parser.http_major ? parser.http_major : 1, parser.http_major ? parser.http_minor : 1, response, http_status_str((http_status)response)));
 
 		rheaders.CreateHeader("Date", InspIRCd::TimeString(ServerInstance->Time(), "%a, %d %b %Y %H:%M:%S GMT", true));
 		rheaders.CreateHeader("Server", INSPIRCD_BRANCH);
diff --git a/src/modules/m_ircv3_msgid.cpp b/src/modules/m_ircv3_msgid.cpp
index d6c603a6b..3e08d5e4a 100644
--- a/src/modules/m_ircv3_msgid.cpp
+++ b/src/modules/m_ircv3_msgid.cpp
@@ -47,7 +47,7 @@ class MsgIdGenerator final
 
 public:
 	MsgIdGenerator()
-		: strid(InspIRCd::Format("%s~%lu~", ServerInstance->Config->GetSID().c_str(), ServerInstance->startup_time))
+		: strid(INSP_FORMAT("{}~{}~", ServerInstance->Config->GetSID(), ServerInstance->startup_time))
 		, baselen(strid.length())
 	{
 	}
diff --git a/src/modules/m_joinflood.cpp b/src/modules/m_joinflood.cpp
index b6c5afb3d..08252532e 100644
--- a/src/modules/m_joinflood.cpp
+++ b/src/modules/m_joinflood.cpp
@@ -195,7 +195,8 @@ public:
 			{
 				f->clear();
 				f->lock();
-				memb->chan->WriteNotice(InspIRCd::Format("This channel has been closed to new users for %u seconds because there have been more than %d joins in %d seconds.", duration, f->joins, f->secs));
+				memb->chan->WriteNotice(INSP_FORMAT("This channel has been closed to new users for {} seconds because there have been more than {} joins in {} seconds.",
+					duration, f->joins, f->secs));
 			}
 		}
 	}
diff --git a/src/modules/m_kicknorejoin.cpp b/src/modules/m_kicknorejoin.cpp
index 588adf73c..8634fca10 100644
--- a/src/modules/m_kicknorejoin.cpp
+++ b/src/modules/m_kicknorejoin.cpp
@@ -145,7 +145,7 @@ public:
 			const KickRejoinData* data = kr.ext.Get(chan);
 			if ((data) && !invapi->IsInvited(user, chan) && (!data->canjoin(user)))
 			{
-				user->WriteNumeric(ERR_UNAVAILRESOURCE, chan->name, InspIRCd::Format("You must wait %u seconds after being kicked to rejoin (+J is set)", data->delay));
+				user->WriteNumeric(ERR_UNAVAILRESOURCE, chan->name, INSP_FORMAT("You must wait {} seconds after being kicked to rejoin (+J is set)", data->delay));
 				return MOD_RES_DENY;
 			}
 		}
diff --git a/src/modules/m_knock.cpp b/src/modules/m_knock.cpp
index a901b7721..330d50c58 100644
--- a/src/modules/m_knock.cpp
+++ b/src/modules/m_knock.cpp
@@ -89,19 +89,19 @@ public:
 
 		if (c->HasUser(user))
 		{
-			user->WriteNumeric(ERR_KNOCKONCHAN, c->name, InspIRCd::Format("Can't KNOCK on %s, you are already on that channel.", c->name.c_str()));
+			user->WriteNumeric(ERR_KNOCKONCHAN, c->name, INSP_FORMAT("Can't KNOCK on {}, you are already on that channel.", c->name));
 			return CmdResult::FAILURE;
 		}
 
 		if (c->IsModeSet(noknockmode))
 		{
-			user->WriteNumeric(ERR_CANNOTKNOCK, InspIRCd::Format("Can't KNOCK on %s, +K is set.", c->name.c_str()));
+			user->WriteNumeric(ERR_CANNOTKNOCK, INSP_FORMAT("Can't KNOCK on {}, +K is set.", c->name));
 			return CmdResult::FAILURE;
 		}
 
 		if (!c->IsModeSet(inviteonlymode))
 		{
-			user->WriteNumeric(ERR_CHANOPEN, c->name, InspIRCd::Format("Can't KNOCK on %s, channel is not invite only so knocking is pointless!", c->name.c_str()));
+			user->WriteNumeric(ERR_CHANOPEN, c->name, INSP_FORMAT("Can't KNOCK on {}, channel is not invite only so knocking is pointless!", c->name));
 			return CmdResult::FAILURE;
 		}
 
@@ -131,7 +131,7 @@ public:
 
 		if (notify & KN_SEND_NOTICE)
 		{
-			c->WriteNotice(InspIRCd::Format("User %s is KNOCKing on %s (%s)", user->nick.c_str(), c->name.c_str(), parameters[1].c_str()), status);
+			c->WriteNotice(INSP_FORMAT("User {} is KNOCKing on {} ({})", user->nick, c->name, parameters[1]), status);
 			user->WriteNotice("KNOCKing on " + c->name);
 		}
 
diff --git a/src/modules/m_monitor.cpp b/src/modules/m_monitor.cpp
index e5cbedc29..3e2b9d514 100644
--- a/src/modules/m_monitor.cpp
+++ b/src/modules/m_monitor.cpp
@@ -277,7 +277,7 @@ class CommandMonitor final
 			if (result == IRCv3::Monitor::Manager::WR_TOOMANY)
 			{
 				// List is full, send error which includes the remaining nicks that were not processed
-				user->WriteNumeric(ERR_MONLISTFULL, maxmonitor, InspIRCd::Format("%s%s%s", nick.c_str(), (ss.StreamEnd() ? "" : ","), ss.GetRemaining().c_str()), "Monitor list is full");
+				user->WriteNumeric(ERR_MONLISTFULL, maxmonitor, INSP_FORMAT("{}{}{}", nick, (ss.StreamEnd() ? "" : ","), ss.GetRemaining()), "Monitor list is full");
 				break;
 			}
 			else if (result != IRCv3::Monitor::Manager::WR_OK)
diff --git a/src/modules/m_nickflood.cpp b/src/modules/m_nickflood.cpp
index 7bd3fcc14..c830b5b8e 100644
--- a/src/modules/m_nickflood.cpp
+++ b/src/modules/m_nickflood.cpp
@@ -158,8 +158,8 @@ public:
 
 				if (f->islocked())
 				{
-					user->WriteNumeric(ERR_CANTCHANGENICK, InspIRCd::Format("%s has been locked for nickchanges for %u seconds because there have been more than %u nick changes in %u seconds",
-							memb->chan->name.c_str(), duration, f->nicks, f->secs));
+					user->WriteNumeric(ERR_CANTCHANGENICK, INSP_FORMAT("{} has been locked for nickchanges for {} seconds because there have been more than {} nick changes in {} seconds",
+							memb->chan->name, duration, f->nicks, f->secs));
 					return MOD_RES_DENY;
 				}
 
@@ -167,7 +167,7 @@ public:
 				{
 					f->clear();
 					f->lock();
-					memb->chan->WriteNotice(InspIRCd::Format("No nick changes are allowed for %u seconds because there have been more than %u nick changes in %u seconds.",
+					memb->chan->WriteNotice(INSP_FORMAT("No nick changes are allowed for {} seconds because there have been more than {} nick changes in {} seconds.",
 						duration, f->nicks, f->secs));
 					return MOD_RES_DENY;
 				}
diff --git a/src/modules/m_nokicks.cpp b/src/modules/m_nokicks.cpp
index 5bacd2584..a829a9ac9 100644
--- a/src/modules/m_nokicks.cpp
+++ b/src/modules/m_nokicks.cpp
@@ -49,8 +49,8 @@ public:
 		if (!extban.GetStatus(source, memb->chan).check(!modeset))
 		{
 			// Can't kick with Q in place, not even opers with override, and founders
-			source->WriteNumeric(ERR_RESTRICTED, memb->chan->name, InspIRCd::Format("Can't kick user %s from channel (%s)",
-				memb->user->nick.c_str(), modeset ? "+Q is set" : "you're extbanned"));
+			source->WriteNumeric(ERR_RESTRICTED, memb->chan->name, INSP_FORMAT("Can't kick user {} from channel ({})",
+				memb->user->nick, modeset ? "+Q is set" : "you're extbanned"));
 			return MOD_RES_DENY;
 		}
 		return MOD_RES_PASSTHRU;
diff --git a/src/modules/m_nonicks.cpp b/src/modules/m_nonicks.cpp
index 8b6ee9676..6064c883c 100644
--- a/src/modules/m_nonicks.cpp
+++ b/src/modules/m_nonicks.cpp
@@ -59,8 +59,8 @@ public:
 			bool modeset = memb->chan->IsModeSet(nn);
 			if (!extban.GetStatus(user, memb->chan).check(!modeset))
 			{
-				user->WriteNumeric(ERR_CANTCHANGENICK, InspIRCd::Format("Can't change nickname while on %s (%s)",
-					memb->chan->name.c_str(), modeset ? "+N is set" : "you're extbanned"));
+				user->WriteNumeric(ERR_CANTCHANGENICK, INSP_FORMAT("Can't change nickname while on {} ({})",
+					memb->chan->name, modeset ? "+N is set" : "you're extbanned"));
 				return MOD_RES_DENY;
 			}
 		}
diff --git a/src/modules/m_operchans.cpp b/src/modules/m_operchans.cpp
index 10e55a370..f5ed14e09 100644
--- a/src/modules/m_operchans.cpp
+++ b/src/modules/m_operchans.cpp
@@ -79,7 +79,7 @@ public:
 	{
 		if (!override && chan && chan->IsModeSet(oc) && !user->IsOper())
 		{
-			user->WriteNumeric(ERR_CANTJOINOPERSONLY, chan->name, InspIRCd::Format("Only server operators may join %s (+O is set)", chan->name.c_str()));
+			user->WriteNumeric(ERR_CANTJOINOPERSONLY, chan->name, INSP_FORMAT("Only server operators may join {} (+O is set)", chan->name));
 			return MOD_RES_DENY;
 		}
 		return MOD_RES_PASSTHRU;
diff --git a/src/modules/m_operlevels.cpp b/src/modules/m_operlevels.cpp
index ebdc86f16..aa9efdd20 100644
--- a/src/modules/m_operlevels.cpp
+++ b/src/modules/m_operlevels.cpp
@@ -51,7 +51,7 @@ public:
 						source->nick.c_str(), source_level, dest->nick.c_str(), dest_level, reason.c_str());
 				}
 				dest->WriteNotice("*** Oper " + source->nick + " attempted to /KILL you!");
-				source->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - Oper %s is a higher level than you", dest->nick.c_str()));
+				source->WriteNumeric(ERR_NOPRIVILEGES, INSP_FORMAT("Permission Denied - Oper {} is a higher level than you", dest->nick));
 				return MOD_RES_DENY;
 			}
 		}
diff --git a/src/modules/m_override.cpp b/src/modules/m_override.cpp
index 5c1125340..6c07a8a1d 100644
--- a/src/modules/m_override.cpp
+++ b/src/modules/m_override.cpp
@@ -119,7 +119,7 @@ private:
 		}
 
 		if (NoisyOverride)
-			chan->WriteRemoteNotice(InspIRCd::Format("%s used oper override to bypass %s", user->nick.c_str(), bypasswhat));
+			chan->WriteRemoteNotice(INSP_FORMAT("{} used oper override to bypass {}", user->nick, bypasswhat));
 		ServerInstance->SNO.WriteGlobalSno('v', user->nick+" used oper override to bypass " + mode + " on " + chan->name);
 		return MOD_RES_ALLOW;
 	}
diff --git a/src/modules/m_redirect.cpp b/src/modules/m_redirect.cpp
index 521ccb091..7cbe8d7e8 100644
--- a/src/modules/m_redirect.cpp
+++ b/src/modules/m_redirect.cpp
@@ -57,12 +57,12 @@ public:
 			auto* c = ServerInstance->Channels.Find(parameter);
 			if (!c)
 			{
-				source->WriteNumeric(690, InspIRCd::Format("Target channel %s must exist to be set as a redirect.", parameter.c_str()));
+				source->WriteNumeric(690, INSP_FORMAT("Target channel {} must exist to be set as a redirect.", parameter));
 				return false;
 			}
 			else if (c->GetPrefixValue(source) < OP_VALUE)
 			{
-				source->WriteNumeric(690, InspIRCd::Format("You must be opped on %s to set it as a redirect.", parameter.c_str()));
+				source->WriteNumeric(690, INSP_FORMAT("You must be opped on {} to set it as a redirect.", parameter));
 				return false;
 			}
 		}
diff --git a/src/modules/m_remove.cpp b/src/modules/m_remove.cpp
index 482477eb7..113062b30 100644
--- a/src/modules/m_remove.cpp
+++ b/src/modules/m_remove.cpp
@@ -83,7 +83,7 @@ public:
 
 		if (!channel->HasUser(target))
 		{
-			user->WriteNotice(InspIRCd::Format("*** User %s is not on channel %s", target->nick.c_str(), channel->name.c_str()));
+			user->WriteNotice(INSP_FORMAT("*** User {} is not on channel {}", target->nick, channel->name));
 			return CmdResult::FAILURE;
 		}
 
@@ -129,21 +129,21 @@ public:
 				/* Build up the part reason string. */
 				std::string reason = "Removed by " + user->nick + ": " + reasonparam;
 
-				channel->WriteRemoteNotice(InspIRCd::Format("%s removed %s from the channel", user->nick.c_str(), target->nick.c_str()));
+				channel->WriteRemoteNotice(INSP_FORMAT("{} removed {} from the channel", user->nick, target->nick));
 				target->WriteNotice("*** " + user->nick + " removed you from " + channel->name + " with the message: " + reasonparam);
 
 				channel->PartUser(target, reason);
 			}
 			else
 			{
-				user->WriteNotice(InspIRCd::Format("*** You do not have access to /REMOVE %s from %s", target->nick.c_str(), channel->name.c_str()));
+				user->WriteNotice(INSP_FORMAT("*** You do not have access to /REMOVE {} from {}", target->nick, channel->name));
 				return CmdResult::FAILURE;
 			}
 		}
 		else
 		{
 			/* m_nokicks.so was loaded and +Q was set, block! */
-			user->WriteNumeric(ERR_RESTRICTED, channel->name, InspIRCd::Format("Can't remove user %s from channel (+Q is set)", target->nick.c_str()));
+			user->WriteNumeric(ERR_RESTRICTED, channel->name, INSP_FORMAT("Can't remove user {} from channel (+Q is set)", target->nick));
 			return CmdResult::FAILURE;
 		}
 
diff --git a/src/modules/m_repeat.cpp b/src/modules/m_repeat.cpp
index 33c784a5b..ec2568779 100644
--- a/src/modules/m_repeat.cpp
+++ b/src/modules/m_repeat.cpp
@@ -318,15 +318,15 @@ private:
 	{
 		if (ms.MaxLines && settings.Lines > ms.MaxLines)
 		{
-			source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format(
-				"The line number you specified is too big. Maximum allowed is %lu.", ms.MaxLines)));
+			source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, INSP_FORMAT(
+				"The line number you specified is too big. Maximum allowed is {}.", ms.MaxLines)));
 			return false;
 		}
 
 		if (ms.MaxSecs && settings.Seconds > ms.MaxSecs)
 		{
-			source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format(
-				"The seconds you specified are too big. Maximum allowed is %lu.", ms.MaxSecs)));
+			source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, INSP_FORMAT(
+				"The seconds you specified are too big. Maximum allowed is {}.", ms.MaxSecs)));
 			return false;
 		}
 
@@ -336,8 +336,8 @@ private:
 				source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter,
 					"The server administrator has disabled matching on edit distance."));
 			else
-				source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format(
-					"The distance you specified is too big. Maximum allowed is %u.", ms.MaxDiff)));
+				source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, INSP_FORMAT(
+					"The distance you specified is too big. Maximum allowed is {}.", ms.MaxDiff)));
 			return false;
 		}
 
@@ -347,8 +347,8 @@ private:
 				source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter,
 					"The server administrator has disabled backlog matching."));
 			else
-				source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format(
-					"The backlog you specified is too big. Maximum allowed is %lu.", ms.MaxBacklog)));
+				source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, INSP_FORMAT(
+					"The backlog you specified is too big. Maximum allowed is {}.", ms.MaxBacklog)));
 			return false;
 		}
 
@@ -438,7 +438,7 @@ public:
 		data["max-diff"] = ConvToStr(rm.ms.MaxDiff);
 		data["max-backlog"] = ConvToStr(rm.ms.MaxBacklog);
 
-		compatdata = InspIRCd::Format("%lu:%lu:%u:%lu", rm.ms.MaxLines, rm.ms.MaxSecs,
+		compatdata = INSP_FORMAT("{}:{}:{}:{}", rm.ms.MaxLines, rm.ms.MaxSecs,
 			rm.ms.MaxDiff, rm.ms.MaxBacklog);
 	}
 };
diff --git a/src/modules/m_rmode.cpp b/src/modules/m_rmode.cpp
index dc1546ccc..4f6361efd 100644
--- a/src/modules/m_rmode.cpp
+++ b/src/modules/m_rmode.cpp
@@ -53,8 +53,8 @@ public:
 
 		if (chan->GetPrefixValue(user) < mh->GetLevelRequired(false))
 		{
-			user->WriteNumeric(Numerics::ChannelPrivilegesNeeded(chan, mh->GetLevelRequired(false), InspIRCd::Format("unset channel mode %c (%s)",
-				mh->GetModeChar(), mh->name.c_str())));
+			user->WriteNumeric(Numerics::ChannelPrivilegesNeeded(chan, mh->GetLevelRequired(false), INSP_FORMAT("unset channel mode {} ({})",
+				mh->GetModeChar(), mh->name)));
 			return CmdResult::FAILURE;
 		}
 
diff --git a/src/modules/m_satopic.cpp b/src/modules/m_satopic.cpp
index 88beb9274..0fba5b0af 100644
--- a/src/modules/m_satopic.cpp
+++ b/src/modules/m_satopic.cpp
@@ -51,7 +51,7 @@ public:
 			const std::string newTopic(parameters[1], 0, ServerInstance->Config->Limits.MaxTopic);
 			if (target->topic == newTopic)
 			{
-				user->WriteNotice(InspIRCd::Format("The topic on %s is already what you are trying to change it to.", target->name.c_str()));
+				user->WriteNotice(INSP_FORMAT("The topic on {} is already what you are trying to change it to.", target->name));
 				return CmdResult::SUCCESS;
 			}
 
diff --git a/src/modules/m_securelist.cpp b/src/modules/m_securelist.cpp
index 39401697c..e07c3b973 100644
--- a/src/modules/m_securelist.cpp
+++ b/src/modules/m_securelist.cpp
@@ -104,9 +104,9 @@ public:
 		// If <securehost:showmsg> is set then tell the user that they need to wait.
 		if (showmsg)
 		{
-			user->WriteNotice(InspIRCd::Format("*** You cannot view the channel list right now. Please %stry again in %s.",
+			user->WriteNotice(INSP_FORMAT("*** You cannot view the channel list right now. Please {}try again in {}.",
 				exemptregistered ? "log in to an account or " : "",
-				Duration::ToString(maxwaittime - ServerInstance->Time()).c_str()));
+				Duration::ToString(maxwaittime - ServerInstance->Time())));
 		}
 
 		// The client might be waiting on a response to do something so send them an
diff --git a/src/modules/m_servprotect.cpp b/src/modules/m_servprotect.cpp
index c9f25c45b..0cfb262e6 100644
--- a/src/modules/m_servprotect.cpp
+++ b/src/modules/m_servprotect.cpp
@@ -93,7 +93,7 @@ public:
 				if ((u->IsModeSet(bm)) && (memb) && (memb->HasMode(pm)))
 				{
 					/* BZZZT, Denied! */
-					user->WriteNumeric(ERR_RESTRICTED, chan->name, InspIRCd::Format("You are not permitted to remove privileges from %s services", ServerInstance->Config->Network.c_str()));
+					user->WriteNumeric(ERR_RESTRICTED, chan->name, INSP_FORMAT("You are not permitted to remove privileges from {} services", ServerInstance->Config->Network));
 					return MOD_RES_DENY;
 				}
 			}
@@ -109,7 +109,7 @@ public:
 
 		if (dst->IsModeSet(bm))
 		{
-			src->WriteNumeric(ERR_KILLDENY, InspIRCd::Format("You are not permitted to kill %s services!", ServerInstance->Config->Network.c_str()));
+			src->WriteNumeric(ERR_KILLDENY, INSP_FORMAT("You are not permitted to kill {} services!", ServerInstance->Config->Network));
 			ServerInstance->SNO.WriteGlobalSno('a', src->nick+" tried to kill service "+dst->nick+" ("+reason+")");
 			return MOD_RES_DENY;
 		}
diff --git a/src/modules/m_sethost.cpp b/src/modules/m_sethost.cpp
index e1534f8dd..00bd92580 100644
--- a/src/modules/m_sethost.cpp
+++ b/src/modules/m_sethost.cpp
@@ -88,7 +88,7 @@ public:
 		{
 			// A hostname can not contain NUL, LF, CR, or SPACE.
 			if (chr == 0x00 || chr == 0x0A || chr == 0x0D || chr == 0x20)
-				throw ModuleException(this, InspIRCd::Format("<hostname:charmap> can not contain character 0x%02X (%c)", chr, chr));
+				throw ModuleException(this, INSP_FORMAT("<hostname:charmap> can not contain character 0x{:02X} ({})", chr, chr));
 			newhostmap.set(static_cast<unsigned char>(chr));
 		}
 		std::swap(newhostmap, cmd.hostmap);
diff --git a/src/modules/m_spanningtree/fjoin.cpp b/src/modules/m_spanningtree/fjoin.cpp
index c2152cf54..ca06755ca 100644
--- a/src/modules/m_spanningtree/fjoin.cpp
+++ b/src/modules/m_spanningtree/fjoin.cpp
@@ -22,7 +22,9 @@
  */
 
 
+
 #include "inspircd.h"
+
 #include "commands.h"
 #include "treeserver.h"
 #include "treesocket.h"
@@ -272,8 +274,8 @@ void CommandFJoin::LowerTS(Channel* chan, time_t TS, const std::string& newname)
 	if (Utils->AnnounceTSChange)
 	{
 		// WriteRemoteNotice is not used here because the message only needs to go to the local server.
-		chan->WriteNotice(InspIRCd::Format("Creation time of %s changed from %s to %s", newname.c_str(),
-			InspIRCd::TimeString(chan->age).c_str(), InspIRCd::TimeString(TS).c_str()));
+		chan->WriteNotice(INSP_FORMAT("Creation time of {} changed from {} to {}", newname,
+			InspIRCd::TimeString(chan->age), InspIRCd::TimeString(TS)));
 	}
 
 	// While the name is equal in case-insensitive compare, it might differ in case; use the remote version
diff --git a/src/modules/m_spanningtree/main.cpp b/src/modules/m_spanningtree/main.cpp
index 138a369d6..833e633df 100644
--- a/src/modules/m_spanningtree/main.cpp
+++ b/src/modules/m_spanningtree/main.cpp
@@ -166,7 +166,7 @@ void ModuleSpanningTree::ShowLinks(TreeServer* Current, User* user, int hops)
 
 	user->WriteNumeric(RPL_LINKS, Current->GetName(),
 			(((Utils->FlatLinks) && (!user->IsOper())) ? ServerInstance->Config->GetServerName() : Parent),
-			InspIRCd::Format("%d %s", (((Utils->FlatLinks) && (!user->IsOper())) ? 0 : hops), Current->GetDesc().c_str()));
+			INSP_FORMAT("{} {}", (((Utils->FlatLinks) && (!user->IsOper())) ? 0 : hops), Current->GetDesc()));
 }
 
 void ModuleSpanningTree::HandleLinks(const CommandBase::Params& parameters, User* user)
@@ -356,25 +356,25 @@ ModResult ModuleSpanningTree::HandleConnect(const CommandBase::Params& parameter
 		{
 			if (InspIRCd::Match(ServerInstance->Config->ServerName, x->Name, ascii_case_insensitive_map))
 			{
-				user->WriteRemoteNotice(InspIRCd::Format("*** CONNECT: Server \002%s\002 is ME, not connecting.", x->Name.c_str()));
+				user->WriteRemoteNotice(INSP_FORMAT("*** CONNECT: Server \002{}\002 is ME, not connecting.", x->Name));
 				return MOD_RES_DENY;
 			}
 
 			TreeServer* CheckDupe = Utils->FindServer(x->Name);
 			if (!CheckDupe)
 			{
-				user->WriteRemoteNotice(InspIRCd::Format("*** CONNECT: Connecting to server: \002%s\002 (%s:%hu)", x->Name.c_str(), (x->HiddenFromStats ? "<hidden>" : x->IPAddr.c_str()), x->Port));
+				user->WriteRemoteNotice(INSP_FORMAT("*** CONNECT: Connecting to server: \002{}\002 ({}:{})", x->Name, (x->HiddenFromStats ? "<hidden>" : x->IPAddr), x->Port));
 				ConnectServer(x);
 				return MOD_RES_DENY;
 			}
 			else
 			{
-				user->WriteRemoteNotice(InspIRCd::Format("*** CONNECT: Server \002%s\002 already exists on the network and is connected via \002%s\002", x->Name.c_str(), CheckDupe->GetParent()->GetName().c_str()));
+				user->WriteRemoteNotice(INSP_FORMAT("*** CONNECT: Server \002{}\002 already exists on the network and is connected via \002{}\002", x->Name, CheckDupe->GetParent()->GetName()));
 				return MOD_RES_DENY;
 			}
 		}
 	}
-	user->WriteRemoteNotice(InspIRCd::Format("*** CONNECT: No server matching \002%s\002 could be found in the config file.", parameters[0].c_str()));
+	user->WriteRemoteNotice(INSP_FORMAT("*** CONNECT: No server matching \002{}\002 could be found in the config file.", parameters[0]));
 	return MOD_RES_DENY;
 }
 
diff --git a/src/modules/m_spanningtree/netburst.cpp b/src/modules/m_spanningtree/netburst.cpp
index da4a60fc6..9e9d66bb7 100644
--- a/src/modules/m_spanningtree/netburst.cpp
+++ b/src/modules/m_spanningtree/netburst.cpp
@@ -24,8 +24,8 @@
 
 
 #include "inspircd.h"
-#include "xline.h"
 #include "listmode.h"
+#include "xline.h"
 
 #include "treesocket.h"
 #include "treeserver.h"
@@ -133,10 +133,11 @@ void TreeSocket::SendServerInfo(TreeServer* from)
 
 	if (proto_version < PROTO_INSPIRCD_4)
 	{
-		this->WriteLine(CommandSInfo::Builder(from, "version", InspIRCd::Format("%s. %s :%s", from->rawbranch.c_str(),
-			from->GetPublicName().c_str(), from->customversion.c_str())));
-		this->WriteLine(CommandSInfo::Builder(from, "fullversion", InspIRCd::Format("%s. %s :[%s] %s", from->rawversion.c_str(),
-			from->GetName().c_str(), from->GetId().c_str(), from->customversion.c_str())));
+		this->WriteLine(CommandSInfo::Builder(from, "version", INSP_FORMAT("{}. {} :{}", from->rawbranch,
+			from->GetPublicName(), from->customversion)));
+
+		this->WriteLine(CommandSInfo::Builder(from, "fullversion", INSP_FORMAT("{}. {} :[{}] {}", from->rawversion,
+			from->GetName(), from->GetId(), from->customversion)));
 	}
 }
 
diff --git a/src/modules/m_spanningtree/num.cpp b/src/modules/m_spanningtree/num.cpp
index 13d951508..e7dd93231 100644
--- a/src/modules/m_spanningtree/num.cpp
+++ b/src/modules/m_spanningtree/num.cpp
@@ -52,7 +52,7 @@ CommandNum::Builder::Builder(SpanningTree::RemoteUser* target, const Numeric::Nu
 	: CmdBuilder("NUM")
 {
 	TreeServer* const server = (numeric.GetServer() ? (static_cast<TreeServer*>(numeric.GetServer())) : Utils->TreeRoot);
-	push(server->GetId()).push(target->uuid).push(InspIRCd::Format("%03u", numeric.GetNumeric()));
+	push(server->GetId()).push(target->uuid).push(INSP_FORMAT("{:03}", numeric.GetNumeric()));
 	const CommandBase::Params& params = numeric.GetParams();
 	if (!params.empty())
 	{
diff --git a/src/modules/m_spanningtree/opertype.cpp b/src/modules/m_spanningtree/opertype.cpp
index 792245669..36fedb94d 100644
--- a/src/modules/m_spanningtree/opertype.cpp
+++ b/src/modules/m_spanningtree/opertype.cpp
@@ -21,7 +21,9 @@
  */
 
 
+
 #include "inspircd.h"
+
 #include "commands.h"
 #include "treeserver.h"
 #include "utils.h"
@@ -103,7 +105,7 @@ CmdResult CommandOpertype::HandleRemote(RemoteUser* u, CommandBase::Params& para
 	std::string extra;
 	if (params.GetTags().find("~name") != params.GetTags().end())
 	{
-		extra += InspIRCd::Format(" (%susing account \x02%s\x02)", automatic ? "automatically " : "",
+		extra += INSP_FORMAT(" ({}using account \x02{}\x02)", automatic ? "automatically " : "",
 			u->oper->GetName().c_str());
 	}
 
diff --git a/src/modules/m_spanningtree/override_map.cpp b/src/modules/m_spanningtree/override_map.cpp
index da17bf12d..7ec4828be 100644
--- a/src/modules/m_spanningtree/override_map.cpp
+++ b/src/modules/m_spanningtree/override_map.cpp
@@ -96,7 +96,7 @@ static std::vector<std::string> GetMap(User* user, TreeServer* current, size_t m
 	// Pad with spaces until its at max len, max_len must always be >= my names length
 	buffer.append(max_len - current->GetName().length(), ' ');
 
-	buffer += InspIRCd::Format("%5zu [%5.2f%%]", current->UserCount, percent);
+	buffer += INSP_FORMAT("{:5} [{:5.2}%]", current->UserCount, percent);
 
 	if (user->IsOper())
 	{
@@ -219,8 +219,10 @@ CmdResult CommandMap::Handle(User* user, const Params& parameters)
 	size_t totusers = ServerInstance->Users.GetUsers().size();
 	float avg_users = (float) totusers / Utils->serverlist.size();
 
-	user->WriteRemoteNumeric(RPL_MAPUSERS, InspIRCd::Format("%u server%s and %u user%s, average %.2f users per server",
-		(unsigned int)Utils->serverlist.size(), (Utils->serverlist.size() > 1 ? "s" : ""), (unsigned int)totusers, (totusers > 1 ? "s" : ""), avg_users));
+	user->WriteRemoteNumeric(RPL_MAPUSERS, INSP_FORMAT("{} server{} and {} user{}, average {:.2} users per server",
+		Utils->serverlist.size(), (Utils->serverlist.size() > 1 ? "s" : ""), totusers,
+		(totusers > 1 ? "s" : ""), avg_users));
+
 	user->WriteRemoteNumeric(RPL_ENDMAP, "End of /MAP");
 
 	return CmdResult::SUCCESS;
diff --git a/src/modules/m_spanningtree/rconnect.cpp b/src/modules/m_spanningtree/rconnect.cpp
index 7a0df868e..e8e145f25 100644
--- a/src/modules/m_spanningtree/rconnect.cpp
+++ b/src/modules/m_spanningtree/rconnect.cpp
@@ -42,7 +42,7 @@ CmdResult CommandRConnect::Handle(User* user, const Params& parameters)
 	/* First see if the server which is being asked to connect to another server in fact exists */
 	if (!Utils->FindServerMask(parameters[0]))
 	{
-		user->WriteRemoteNotice(InspIRCd::Format("*** RCONNECT: Server \002%s\002 isn't connected to the network!", parameters[0].c_str()));
+		user->WriteRemoteNotice(INSP_FORMAT("*** RCONNECT: Server \002{}\002 isn't connected to the network!", parameters[0]));
 		return CmdResult::FAILURE;
 	}
 
diff --git a/src/modules/m_spanningtree/rsquit.cpp b/src/modules/m_spanningtree/rsquit.cpp
index 437b25324..d938a6225 100644
--- a/src/modules/m_spanningtree/rsquit.cpp
+++ b/src/modules/m_spanningtree/rsquit.cpp
@@ -44,13 +44,13 @@ CmdResult CommandRSQuit::Handle(User* user, const Params& parameters)
 	server_target = Utils->FindServerMask(parameters[0]);
 	if (!server_target)
 	{
-		user->WriteRemoteNotice(InspIRCd::Format("*** RSQUIT: Server \002%s\002 isn't connected to the network!", parameters[0].c_str()));
+		user->WriteRemoteNotice(INSP_FORMAT("*** RSQUIT: Server \002{}\002 isn't connected to the network!", parameters[0]));
 		return CmdResult::FAILURE;
 	}
 
 	if (server_target->IsRoot())
 	{
-		user->WriteRemoteNotice(InspIRCd::Format("*** RSQUIT: Foolish mortal, you cannot make a server SQUIT itself! (%s matches local server name)", parameters[0].c_str()));
+		user->WriteRemoteNotice(INSP_FORMAT("*** RSQUIT: Foolish mortal, you cannot make a server SQUIT itself! ({} matches local server name)", parameters[0]));
 		return CmdResult::FAILURE;
 	}
 
diff --git a/src/modules/m_sslinfo.cpp b/src/modules/m_sslinfo.cpp
index a30da84c8..4b9817c23 100644
--- a/src/modules/m_sslinfo.cpp
+++ b/src/modules/m_sslinfo.cpp
@@ -181,17 +181,17 @@ private:
 		ssl_cert* cert = sslapi.GetCertificate(target);
 		if (!cert)
 		{
-			source->WriteNotice(InspIRCd::Format("*** %s is not connected using TLS.", target->nick.c_str()));
+			source->WriteNotice(INSP_FORMAT("*** {} is not connected using TLS.", target->nick));
 		}
 		else if (cert->GetError().length())
 		{
-			source->WriteNotice(InspIRCd::Format("*** %s is connected using TLS but has not specified a valid client certificate (%s).",
-				target->nick.c_str(), cert->GetError().c_str()));
+			source->WriteNotice(INSP_FORMAT("*** {} is connected using TLS but has not specified a valid client certificate ({}).",
+				target->nick, cert->GetError()));
 		}
 		else if (!verbose)
 		{
-			source->WriteNotice(InspIRCd::Format("*** %s is connected using TLS with a valid client certificate (%s).",
-				target->nick.c_str(), cert->GetFingerprint().c_str()));
+			source->WriteNotice(INSP_FORMAT("*** {} is connected using TLS with a valid client certificate ({}).",
+				target->nick, cert->GetFingerprint()));
 		}
 		else
 		{
@@ -243,9 +243,9 @@ private:
 
 		if (sslonlymode)
 		{
-			source->WriteNotice(InspIRCd::Format("*** %s %s have channel mode +%c (%s) set.",
-				chan->name.c_str(), chan->IsModeSet(sslonlymode) ? "does" : "does not",
-				sslonlymode->GetModeChar(), sslonlymode->name.c_str()));
+			source->WriteNotice(INSP_FORMAT("*** {} {} have channel mode +{} ({}) set.",
+				chan->name, chan->IsModeSet(sslonlymode) ? "does" : "does not",
+				sslonlymode->GetModeChar(), sslonlymode->name));
 		}
 
 		for (const auto& [u, _] : chan->GetUsers())
@@ -317,7 +317,7 @@ public:
 		{
 			whois.SendLine(RPL_WHOISSECURE, "is using a secure connection");
 			if ((!cmd.operonlyfp || whois.IsSelfWhois() || whois.GetSource()->IsOper()) && !cert->fingerprint.empty())
-				whois.SendLine(RPL_WHOISCERTFP, InspIRCd::Format("has TLS client certificate fingerprint %s", cert->fingerprint.c_str()));
+				whois.SendLine(RPL_WHOISCERTFP, INSP_FORMAT("has TLS client certificate fingerprint {}", cert->fingerprint));
 		}
 	}
 
diff --git a/src/modules/m_sslmodes.cpp b/src/modules/m_sslmodes.cpp
index d0a184cf3..150aca0b5 100644
--- a/src/modules/m_sslmodes.cpp
+++ b/src/modules/m_sslmodes.cpp
@@ -100,7 +100,7 @@ public:
 
 					if (nonssl)
 					{
-						source->WriteNumeric(ERR_ALLMUSTSSL, channel->name, InspIRCd::Format("All members of the channel must be connected via TLS (%zu/%zu are non-TLS)",
+						source->WriteNumeric(ERR_ALLMUSTSSL, channel->name, INSP_FORMAT("All members of the channel must be connected via TLS ({}/{} are non-TLS)",
 							nonssl, channel->GetUsers().size()));
 						return false;
 					}
diff --git a/src/modules/m_svshold.cpp b/src/modules/m_svshold.cpp
index 81562d78c..291ded353 100644
--- a/src/modules/m_svshold.cpp
+++ b/src/modules/m_svshold.cpp
@@ -217,7 +217,7 @@ public:
 
 		if (rl)
 		{
-			user->WriteNumeric(ERR_ERRONEUSNICKNAME, newnick, InspIRCd::Format("Services reserved nickname: %s", rl->reason.c_str()));
+			user->WriteNumeric(ERR_ERRONEUSNICKNAME, newnick, INSP_FORMAT("Services reserved nickname: {}", rl->reason));
 			return MOD_RES_DENY;
 		}
 
diff --git a/src/modules/m_timedbans.cpp b/src/modules/m_timedbans.cpp
index db41acaff..c3986ac70 100644
--- a/src/modules/m_timedbans.cpp
+++ b/src/modules/m_timedbans.cpp
@@ -151,8 +151,8 @@ public:
 
 		if (sendnotice)
 		{
-			const std::string message = InspIRCd::Format("Timed ban %s added by %s on %s lasting for %s.",
-			mask.c_str(), user->nick.c_str(), channel->name.c_str(), Duration::ToString(duration).c_str());
+			const std::string message = INSP_FORMAT("Timed ban {} added by {} on {} lasting for {}.",
+				mask, user->nick, channel->name, Duration::ToString(duration));
 
 			// If halfop is loaded, send notice to halfops and above, otherwise send to ops and above
 			PrefixMode* mh = ServerInstance->Modes.FindNearestPrefixMode(HALFOP_VALUE);
@@ -256,8 +256,8 @@ public:
 		{
 			if (cmd.sendnotice)
 			{
-				const std::string message = InspIRCd::Format("Timed ban %s set by %s on %s has expired.",
-				timedban.mask.c_str(), timedban.setter.c_str(), timedban.chan->name.c_str());
+				const std::string message = INSP_FORMAT("Timed ban {} set by {} on {} has expired.",
+					timedban.mask, timedban.setter, timedban.chan->name);
 
 				// If halfop is loaded, send notice to halfops and above, otherwise send to ops and above
 				PrefixMode* mh = ServerInstance->Modes.FindNearestPrefixMode(HALFOP_VALUE);
diff --git a/src/modules/m_tline.cpp b/src/modules/m_tline.cpp
index caa942ec9..52bb3cec4 100644
--- a/src/modules/m_tline.cpp
+++ b/src/modules/m_tline.cpp
@@ -63,10 +63,11 @@ public:
 		if (n_matched)
 		{
 			float p = (n_matched / (float)n_counted) * 100;
-			user->WriteNotice(InspIRCd::Format("*** TLINE: Counted %lu user(s). Matched '%s' against %u user(s) (%0.2f%% of the userbase). %u by hostname and %u by IP address.", n_counted, parameters[0].c_str(), n_matched, p, n_match_host, n_match_ip));
+			user->WriteNotice(INSP_FORMAT("*** TLINE: Counted {} user(s). Matched '{}' against {} user(s) ({:0.2}% of the userbase). {} by hostname and {} by IP address.",
+				n_counted, parameters[0], n_matched, p, n_match_host, n_match_ip));
 		}
 		else
-			user->WriteNotice(InspIRCd::Format("*** TLINE: Counted %lu user(s). Matched '%s' against no user(s).", n_counted, parameters[0].c_str()));
+			user->WriteNotice(INSP_FORMAT("*** TLINE: Counted {} user(s). Matched '{}' against no user(s).", n_counted, parameters[0]));
 
 		return CmdResult::SUCCESS;
 	}
diff --git a/src/modules/m_uninvite.cpp b/src/modules/m_uninvite.cpp
index 6071e30bf..a4a7ad1c1 100644
--- a/src/modules/m_uninvite.cpp
+++ b/src/modules/m_uninvite.cpp
@@ -95,7 +95,7 @@ public:
 			{
 				Numeric::Numeric n(ERR_NOTINVITED);
 				n.SetServer(user->server);
-				n.push(u->nick).push(c->name).push(InspIRCd::Format("Is not invited to channel %s", c->name.c_str()));
+				n.push(u->nick).push(c->name).push(INSP_FORMAT("Is not invited to channel {}", c->name));
 				user->WriteRemoteNumeric(n);
 				return CmdResult::FAILURE;
 			}
@@ -105,8 +105,8 @@ public:
 			n.push(c->name).push(u->nick).push("Uninvited");
 			user->WriteRemoteNumeric(n);
 
-			lu->WriteNumeric(RPL_UNINVITED, InspIRCd::Format("You were uninvited from %s by %s", c->name.c_str(), user->nick.c_str()));
-			c->WriteRemoteNotice(InspIRCd::Format("*** %s uninvited %s.", user->nick.c_str(), u->nick.c_str()));
+			lu->WriteNumeric(RPL_UNINVITED, INSP_FORMAT("You were uninvited from {} by {}", c->name, user->nick));
+			c->WriteRemoteNotice(INSP_FORMAT("*** {} uninvited {}.", user->nick, u->nick));
 		}
 
 		return CmdResult::SUCCESS;
diff --git a/src/modules/m_watch.cpp b/src/modules/m_watch.cpp
index 6299bdc17..61b20bcf6 100644
--- a/src/modules/m_watch.cpp
+++ b/src/modules/m_watch.cpp
@@ -113,7 +113,7 @@ class CommandWatch final
 
 		// Do not show how many clients are watching this nick, it's pointless
 		const IRCv3::Monitor::WatchedList& list = manager.GetWatched(user);
-		user->WriteNumeric(RPL_WATCHSTAT, InspIRCd::Format("You have %lu and are on 0 WATCH entries", (unsigned long)list.size()));
+		user->WriteNumeric(RPL_WATCHSTAT, INSP_FORMAT("You have {} and are on 0 WATCH entries", list.size()));
 
 		Numeric::Builder<' '> out(user, RPL_WATCHLIST);
 		for (const auto* entry : list)
diff --git a/src/snomasks.cpp b/src/snomasks.cpp
index 9d3097710..2f4a50948 100644
--- a/src/snomasks.cpp
+++ b/src/snomasks.cpp
@@ -129,7 +129,7 @@ void Snomask::Flush()
 void Snomask::Send(char letter, const std::string& desc, const std::string& msg)
 {
 	ServerInstance->Logs.Normal(desc, msg);
-	const std::string finalmsg = InspIRCd::Format("*** %s: %s", desc.c_str(), msg.c_str());
+	const std::string finalmsg = INSP_FORMAT("*** {}: {}", desc, msg);
 
 	/* Only opers can receive snotices, so we iterate the oper list */
 	for (auto* user : ServerInstance->Users.all_opers)
@@ -148,6 +148,6 @@ std::string Snomask::GetDescription(char letter) const
 	if (!Description.empty())
 		ret += Description;
 	else
-		ret += InspIRCd::Format("SNO-%c", tolower(letter));
+		ret += INSP_FORMAT("SNO-{}", tolower(letter));
 	return ret;
 }
diff --git a/src/socket.cpp b/src/socket.cpp
index 67ca267a4..7f6057ef5 100644
--- a/src/socket.cpp
+++ b/src/socket.cpp
@@ -327,13 +327,13 @@ std::string irc::sockets::sockaddrs::str() const
 			char ip4addr[INET_ADDRSTRLEN];
 			if (!inet_ntop(AF_INET, static_cast<const void*>(&in4.sin_addr), ip4addr, sizeof(ip4addr)))
 				strcpy(ip4addr, "0.0.0.0");
-			return InspIRCd::Format("%s:%u", ip4addr, ntohs(in4.sin_port));
+			return INSP_FORMAT("{}:{}", ip4addr, ntohs(in4.sin_port));
 
 		case AF_INET6:
 			char ip6addr[INET6_ADDRSTRLEN];
 			if (!inet_ntop(AF_INET6, static_cast<const void*>(&in6.sin6_addr), ip6addr, sizeof(ip6addr)))
 				strcpy(ip6addr, "0:0:0:0:0:0:0:0");
-			return InspIRCd::Format("[%s]:%u", ip6addr, ntohs(in6.sin6_port));
+			return INSP_FORMAT("[{}]:{}", ip6addr, ntohs(in6.sin6_port));
 
 		case AF_UNIX:
 			return un.sun_path;
diff --git a/src/usermanager.cpp b/src/usermanager.cpp
index eb881c664..2977d20e7 100644
--- a/src/usermanager.cpp
+++ b/src/usermanager.cpp
@@ -164,7 +164,7 @@ void UserManager::AddUser(int socket, ListenSocket* via, const irc::sockets::soc
 			const char* hooktype = i == via->iohookprovs.begin() ? "hook" : "sslprofile";
 			ServerInstance->Logs.Warning("USERS", "Non-existent I/O hook '%s' in <bind:%s> tag at %s",
 				iohookprovref.GetProvider().c_str(), hooktype, via->bind_tag->source.str().c_str());
-			this->QuitUser(New, InspIRCd::Format("Internal error handling connection (misconfigured %s)", hooktype));
+			this->QuitUser(New, INSP_FORMAT("Internal error handling connection (misconfigured {})", hooktype));
 			return;
 		}
 
@@ -279,7 +279,7 @@ void UserManager::QuitUser(User* user, const std::string& quitmessage, const std
 	ServerInstance->Logs.Debug("USERS", "QuitUser: %s=%s '%s'", user->uuid.c_str(), user->nick.c_str(), quitmessage.c_str());
 	if (localuser)
 	{
-		ClientProtocol::Messages::Error errormsg(InspIRCd::Format("Closing link: (%s) [%s]", user->MakeHost().c_str(), operquitmsg.c_str()));
+		ClientProtocol::Messages::Error errormsg(INSP_FORMAT("Closing link: ({}) [{}]", user->MakeHost(), operquitmsg));
 		localuser->Send(ServerInstance->GetRFCEvents().error, errormsg);
 	}