diff --git a/src/js/export_module.zig b/src/js/export_module.zig
index 1b9a3ae..0a4b4a2 100644
--- a/src/js/export_module.zig
+++ b/src/js/export_module.zig
@@ -34,7 +34,8 @@ const class_runtime = @import("class_runtime.zig");
 ///
 /// The DSL internally manages an atomic refcount for module instances across
 /// different N-API environments, and uses the same env lifecycle to retain a
-/// shared `js.io()` handle for the addon.
+/// shared `js.io()` handle for the addon. Modules with lifecycle hooks also
+/// serialize initialization and cleanup across environments.
 ///
 /// Usage Examples:
 /// ```zig
@@ -66,6 +67,7 @@ pub fn exportModule(comptime Module: type, comptime options: anytype) void {
 
     const State = struct {
         var env_refcount: std.atomic.Value(u32) = std.atomic.Value(u32).init(0);
+        var lifecycle_mutex: std.Io.Mutex = .init;
 
         // addEnvCleanupHook requires a non-null *Data pointer.
         const CleanupData = struct {
@@ -75,6 +77,10 @@ pub fn exportModule(comptime Module: type, comptime options: anytype) void {
 
         fn cleanupHook(_: *CleanupData) void {
             if (has_lifecycle) {
+                const io = io_context.io();
+                lifecycle_mutex.lockUncancelable(io);
+                defer lifecycle_mutex.unlock(io);
+
                 const prev = env_refcount.fetchSub(1, .acq_rel);
                 const new_refcount = prev - 1;
                 if (has_cleanup) {
@@ -96,6 +102,12 @@ pub fn exportModule(comptime Module: type, comptime options: anytype) void {
                 io_context.release();
             };
 
+            const io = io_context.io();
+            if (has_lifecycle) {
+                State.lifecycle_mutex.lockUncancelable(io);
+            }
+            defer if (has_lifecycle) State.lifecycle_mutex.unlock(io);
+
             var prev_refcount: u32 = 0;
             if (has_lifecycle) {
                 prev_refcount = State.env_refcount.fetchAdd(1, .monotonic);