diff --git a/include/ircd/mods/mapi.h b/include/ircd/mods/mapi.h
index 05498079b..75129bd2d 100644
--- a/include/ircd/mods/mapi.h
+++ b/include/ircd/mods/mapi.h
@@ -29,8 +29,8 @@ namespace ircd::mapi
 {
 	struct header;
 	struct metablock;
-	using magic_t = uint16_t;
-	using version_t = uint16_t;
+	using magic_t = uint32_t;
+	using version_t = uint32_t;
 	using meta_data = std::map<string_view, string_view, std::less<>>;
 	using init_func = std::function<void ()>;
 	using fini_func = std::function<void ()>;
@@ -53,7 +53,7 @@ namespace ircd::mapi
 constexpr const ircd::mapi::magic_t
 IRCD_MAPI_MAGIC
 {
-	0x4D41
+	0x112Cd
 };
 
 /// The version number of this module's header.
@@ -74,7 +74,6 @@ struct ircd::mapi::header
 {
 	const magic_t magic {IRCD_MAPI_MAGIC};       // The magic must match
 	const version_t version {IRCD_MAPI_VERSION}; // Version indicator
-	const int32_t _reserved_ {0};                // MBZ
 	const int64_t timestamp {RB_DATECODE};       // Module's compile epoch
 	std::unique_ptr<metablock> meta;             // Non-standard-layout header data
 	mods::mod *self {nullptr};                   // Point to mod instance once loaded
@@ -112,6 +111,6 @@ static_assert
 
 static_assert
 (
-	sizeof(ircd::mapi::header) == 2 + 2 + 4 + 8 + 8 + 8,
+	sizeof(ircd::mapi::header) == 4 + 4 + 8 + 8 + 8,
 	"The MAPI header size has changed on this platform."
 );