diff --git a/system/lib/compiler-rt/stack_limits.S b/system/lib/compiler-rt/stack_limits.S
index 1c4c719fa18af..d6906fe61ab71 100644
--- a/system/lib/compiler-rt/stack_limits.S
+++ b/system/lib/compiler-rt/stack_limits.S
@@ -15,6 +15,7 @@
 #endif
 
 .globaltype __stack_pointer, PTR
+.globl __stack_pointer
 
 .section .globals,"",@
 
@@ -22,7 +23,9 @@
 # using PTR.const rather than using the `emscripten_stack_init`
 .globaltype __stack_end, PTR
 __stack_end:
+.globl __stack_end
 .globaltype __stack_base, PTR
+.globl __stack_base
 __stack_base:
 
 .section .text,"",@
@@ -82,57 +85,6 @@ emscripten_stack_get_free:
   PTR.sub
   end_function
 
-#ifdef __EMSCRIPTEN_WASM_WORKERS__
-# TODO: Relocate the following to its own file wasm_worker.S, but need to figure out how to reference
-# __stack_base and __stack_end globals from a separate file as externs in order for that to work.
-.globl _emscripten_wasm_worker_initialize
-_emscripten_wasm_worker_initialize:
-  .functype _emscripten_wasm_worker_initialize (PTR /*stackLowestAddress*/, i32 /*stackSize*/) -> ()
-
-  // __stack_end = stackLowestAddress + (__builtin_wasm_tls_size() + 15) & -16;
-  local.get 0
-  .globaltype __tls_size, PTR, immutable
-  global.get __tls_size
-  PTR.add
-  PTR.const 0xf
-  PTR.add
-  PTR.const -0x10
-  PTR.and
-  global.set __stack_end
-
-  // __stack_base = stackLowestAddress + stackSize;
-  local.get 0
-  local.get 1
-#ifdef __wasm64__
-  i64.extend_i32_u
-#endif
-  PTR.add
-  global.set __stack_base
-
-// TODO: We'd like to do this here to avoid JS side calls to __set_stack_limits.
-//       (or even better, we'd like to avoid duplicate versions of the stack variables)
-// See https://github.com/emscripten-core/emscripten/issues/16496
-//  global.get __stack_base
-//  global.get __stack_end
-//  .functype __set_stack_limits (PTR, PTR) -> ()
-//  call __set_stack_limits
-
-  // __wasm_init_tls(stackLowestAddress);
-  local.get 0
-  .functype __wasm_init_tls (PTR) -> ()
-  call __wasm_init_tls
-
-  // N.b. The function __wasm_init_tls above does not need
-  // __stack_pointer initialized, and it destroys the value it was set to.
-  // So we must initialize __stack_pointer only *after* completing __wasm_init_tls:
-
-  // __stack_pointer = __stack_base;
-  global.get __stack_base
-  global.set __stack_pointer
-
-  end_function
-#endif
-
 # Add emscripten_stack_init to static ctors
 .section .init_array.1,"",@
 .p2align ALIGN
diff --git a/system/lib/dlmalloc.c b/system/lib/dlmalloc.c
index 68fbe7f332756..f55ff649cfefb 100644
--- a/system/lib/dlmalloc.c
+++ b/system/lib/dlmalloc.c
@@ -21,13 +21,12 @@
 /* XXX Emscripten Tracing API. This defines away the code if tracing is disabled. */
 #include <emscripten/trace.h>
 
-#ifdef __EMSCRIPTEN_WASM_WORKERS__
+#ifdef __EMSCRIPTEN_SHARED_MEMORY__
 #define USE_LOCKS 1
 #endif
 
 /* Make malloc() and free() threadsafe by securing the memory allocations with pthread mutexes. */
 #if __EMSCRIPTEN_PTHREADS__
-#define USE_LOCKS 1
 #define USE_SPIN_LOCKS 0 // Ensure we use pthread_mutex_t.
 #endif
 
diff --git a/system/lib/wasm_worker/wasm_worker_initialize.S b/system/lib/wasm_worker/wasm_worker_initialize.S
new file mode 100644
index 0000000000000..8e144158a3f82
--- /dev/null
+++ b/system/lib/wasm_worker/wasm_worker_initialize.S
@@ -0,0 +1,64 @@
+.extern __stack_pointer
+.extern __stack_base
+.extern __stack_end
+
+#ifdef __wasm64__
+#define PTR i64
+#define ALIGN 3
+#define PTRSTORE .int64
+#else
+#define PTR i32
+#define ALIGN 2
+#define PTRSTORE .int32
+#endif
+
+.globaltype __stack_pointer, PTR
+.globaltype __stack_end, PTR
+.globaltype __stack_base, PTR
+
+.globl _emscripten_wasm_worker_initialize
+_emscripten_wasm_worker_initialize:
+  .functype _emscripten_wasm_worker_initialize (PTR /*stackLowestAddress*/, i32 /*stackSize*/) -> ()
+
+  // __stack_end = stackLowestAddress + (__builtin_wasm_tls_size() + 15) & -16;
+  local.get 0
+  .globaltype __tls_size, PTR, immutable
+  global.get __tls_size
+  PTR.add
+  PTR.const 0xf
+  PTR.add
+  PTR.const -0x10
+  PTR.and
+  global.set __stack_end
+
+  // __stack_base = stackLowestAddress + stackSize;
+  local.get 0
+  local.get 1
+#ifdef __wasm64__
+  i64.extend_i32_u
+#endif
+  PTR.add
+  global.set __stack_base
+
+// TODO: We'd like to do this here to avoid JS side calls to __set_stack_limits.
+//       (or even better, we'd like to avoid duplicate versions of the stack variables)
+// See https://github.com/emscripten-core/emscripten/issues/16496
+//  global.get __stack_base
+//  global.get __stack_end
+//  .functype __set_stack_limits (PTR, PTR) -> ()
+//  call __set_stack_limits
+
+  // __wasm_init_tls(stackLowestAddress);
+  local.get 0
+  .functype __wasm_init_tls (PTR) -> ()
+  call __wasm_init_tls
+
+  // N.b. The function __wasm_init_tls above does not need
+  // __stack_pointer initialized, and it destroys the value it was set to.
+  // So we must initialize __stack_pointer only *after* completing __wasm_init_tls:
+
+  // __stack_pointer = __stack_base;
+  global.get __stack_base
+  global.set __stack_pointer
+
+  end_function
diff --git a/test/core/test_dlfcn_self.exports b/test/core/test_dlfcn_self.exports
index 778003379ab0f..0017bb938a99b 100644
--- a/test/core/test_dlfcn_self.exports
+++ b/test/core/test_dlfcn_self.exports
@@ -9,7 +9,9 @@ __progname_full
 __sig_actions
 __sig_pending
 __signgam
+__stack_base
 __stack_chk_guard
+__stack_end
 __threwValue
 __timezone
 __tzname
diff --git a/test/core/test_em_asm_unicode.out b/test/core/test_em_asm_unicode.out
index 4ef53eab9a770..31caff8090468 100644
--- a/test/core/test_em_asm_unicode.out
+++ b/test/core/test_em_asm_unicode.out
@@ -1 +1 @@
-hello world…
\ No newline at end of file
+hello world…
diff --git a/test/core/test_longjmp.out b/test/core/test_longjmp.out
index 4a412fef09f74..e9cc75258d28d 100644
--- a/test/core/test_longjmp.out
+++ b/test/core/test_longjmp.out
@@ -1,4 +1,4 @@
 first
 result: 1 1
 second
-result: 2 -1
\ No newline at end of file
+result: 2 -1
diff --git a/tools/link.py b/tools/link.py
index 22a8b7494fb04..44fee4acef50e 100644
--- a/tools/link.py
+++ b/tools/link.py
@@ -1413,7 +1413,7 @@ def phase_linker_setup(options, state, newargs):
       'removeRunDependency',
     ]
 
-  if settings.SHARED_MEMORY or settings.RELOCATABLE or settings.ASYNCIFY_LAZY_LOAD_CODE:
+  if settings.PTHREADS or settings.WASM_WORKERS or settings.RELOCATABLE or settings.ASYNCIFY_LAZY_LOAD_CODE:
     settings.IMPORTED_MEMORY = 1
 
   set_initial_memory()
diff --git a/tools/system_libs.py b/tools/system_libs.py
index c202d3770747a..13413638054d4 100644
--- a/tools/system_libs.py
+++ b/tools/system_libs.py
@@ -742,12 +742,17 @@ def vary_on(cls):
 
   @classmethod
   def get_default_variation(cls, **kwargs):
-    return super().get_default_variation(is_mt=settings.PTHREADS, is_ww=settings.WASM_WORKERS and not settings.PTHREADS, **kwargs)
+    return super().get_default_variation(
+      is_mt=settings.PTHREADS,
+      is_ww=settings.SHARED_MEMORY and not settings.PTHREADS,
+      **kwargs
+    )
 
   @classmethod
   def variations(cls):
     combos = super(MTLibrary, cls).variations()
-    # To save on # of variations, pthreads and Wasm workers when used together, just use pthreads variation.
+
+    # These are mutually exclusive, only one flag will be set at any give time.
     return [combo for combo in combos if not combo['is_mt'] or not combo['is_ww']]
 
 
@@ -1452,9 +1457,19 @@ def get_default_variation(cls, **kwargs):
     return super().get_default_variation(stub=not settings.WASM_WORKERS, **kwargs)
 
   def get_files(self):
+    files = []
+    if self.is_stub:
+      files = [
+        'library_wasm_worker_stub.c'
+      ]
+    else:
+      files = [
+        'library_wasm_worker.c',
+        'wasm_worker_initialize.S',
+      ]
     return files_in_path(
         path='system/lib/wasm_worker',
-        filenames=['library_wasm_worker_stub.c' if self.is_stub else 'library_wasm_worker.c'])
+        filenames=files)
 
   def can_use(self):
     # see src/library_wasm_worker.js