diff --git a/ext/opcache/ZendAccelerator.c b/ext/opcache/ZendAccelerator.c
index 6cc3c5c4190a..a3a3e5e85b5c 100644
--- a/ext/opcache/ZendAccelerator.c
+++ b/ext/opcache/ZendAccelerator.c
@@ -46,6 +46,7 @@
 #include "zend_accelerator_util_funcs.h"
 #include "zend_accelerator_hash.h"
 #include "zend_file_cache.h"
+#include "zend_atomic.h"
 #include "ext/pcre/php_pcre.h"
 #include "ext/standard/md5.h"
 #include "ext/hash/php_hash.h"
@@ -143,6 +144,12 @@ static void preload_restart(void);
 # define INCREMENT(v) InterlockedIncrement64(&ZCSG(v))
 # define DECREMENT(v) InterlockedDecrement64(&ZCSG(v))
 # define LOCKVAL(v)   (ZCSG(v))
+#elif defined(__wasi__)
+static uint32_t accel_wasi_mem_usage = 0;
+static uint32_t accel_wasi_restart_in = 0;
+# define INCREMENT(v) __atomic_add_fetch(&accel_wasi_##v, 1, __ATOMIC_SEQ_CST)
+# define DECREMENT(v) __atomic_sub_fetch(&accel_wasi_##v, 1, __ATOMIC_SEQ_CST)
+# define LOCKVAL(v)   __atomic_load_n(&accel_wasi_##v, __ATOMIC_SEQ_CST)
 #endif
 
 #define ZCG_KEY_LEN (MAXPATHLEN * 8)
@@ -266,7 +273,7 @@ static ZEND_INI_MH(accel_include_path_on_modify)
 
 static inline void accel_restart_enter(void)
 {
-#ifdef ZEND_WIN32
+#if defined(ZEND_WIN32) || defined(__wasi__)
 	INCREMENT(restart_in);
 #elif !defined(__wasi__)
 	struct flock restart_in_progress;
@@ -285,7 +292,7 @@ static inline void accel_restart_enter(void)
 
 static inline void accel_restart_leave(void)
 {
-#ifdef ZEND_WIN32
+#if defined(ZEND_WIN32) || defined(__wasi__)
 	ZCSG(restart_in_progress) = false;
 	DECREMENT(restart_in);
 #elif !defined(__wasi__)
@@ -306,7 +313,7 @@ static inline void accel_restart_leave(void)
 static inline int accel_restart_is_active(void)
 {
 	if (ZCSG(restart_in_progress)) {
-#ifdef ZEND_WIN32
+#if defined(ZEND_WIN32) || defined(__wasi__)
 		return LOCKVAL(restart_in) != 0;
 #elif !defined(__wasi__)
 		struct flock restart_check;
@@ -334,7 +341,7 @@ static inline int accel_restart_is_active(void)
 /* Creates a read lock for SHM access */
 static inline zend_result accel_activate_add(void)
 {
-#ifdef ZEND_WIN32
+#if defined(ZEND_WIN32) || defined(__wasi__)
 	SHM_UNPROTECT();
 	INCREMENT(mem_usage);
 	SHM_PROTECT();
@@ -357,7 +364,7 @@ static inline zend_result accel_activate_add(void)
 /* Releases a lock for SHM access */
 static inline void accel_deactivate_sub(void)
 {
-#ifdef ZEND_WIN32
+#if defined(ZEND_WIN32) || defined(__wasi__)
 	if (ZCG(counted)) {
 		SHM_UNPROTECT();
 		DECREMENT(mem_usage);
@@ -380,7 +387,7 @@ static inline void accel_deactivate_sub(void)
 
 static inline void accel_unlock_all(void)
 {
-#ifdef ZEND_WIN32
+#if defined(ZEND_WIN32) || defined(__wasi__)
 	accel_deactivate_sub();
 #elif !defined(__wasi__)
 	if (lock_file == -1) {
@@ -892,7 +899,7 @@ static inline void kill_all_lockers(struct flock *mem_usage_check)
 
 static inline bool accel_is_inactive(void)
 {
-#ifdef ZEND_WIN32
+#if defined(ZEND_WIN32) || defined(__wasi__)
 	/* on Windows, we don't need kill_all_lockers() because SAPIs
 	   that work on Windows don't manage child processes (and we
 	   can't do anything about hanging threads anyway); therefore
@@ -2922,6 +2929,10 @@ static zend_result zend_accel_init_shm(void)
 	ZCSG(start_time) = zend_accel_get_time();
 	ZCSG(last_restart_time) = 0;
 	ZCSG(restart_in_progress) = false;
+#ifdef __wasi__
+	__atomic_store_n(&accel_wasi_mem_usage, 0, __ATOMIC_SEQ_CST);
+	__atomic_store_n(&accel_wasi_restart_in, 0, __ATOMIC_SEQ_CST);
+#endif
 
 	for (i = 0; i < -HT_MIN_MASK; i++) {
 		ZCSG(uninitialized_bucket)[i] = HT_INVALID_IDX;
diff --git a/ext/opcache/zend_file_cache.c b/ext/opcache/zend_file_cache.c
index edcaf689ab7f..011c6a4f7d39 100644
--- a/ext/opcache/zend_file_cache.c
+++ b/ext/opcache/zend_file_cache.c
@@ -96,9 +96,15 @@ static int zend_file_cache_flock(int fd, int op)
 #elif defined(HAVE_FLOCK)
 # define zend_file_cache_flock flock
 #else
-# define LOCK_SH 0
-# define LOCK_EX 1
-# define LOCK_UN 2
+# ifndef LOCK_SH
+#  define LOCK_SH 0
+# endif
+# ifndef LOCK_EX
+#  define LOCK_EX 1
+# endif
+# ifndef LOCK_UN
+#  define LOCK_UN 2
+# endif
 static int zend_file_cache_flock(int fd, int type)
 {
 	return 0;
diff --git a/ext/opcache/zend_shared_alloc.c b/ext/opcache/zend_shared_alloc.c
index 4d97081fb053..c20033b4c5c5 100644
--- a/ext/opcache/zend_shared_alloc.c
+++ b/ext/opcache/zend_shared_alloc.c
@@ -29,6 +29,7 @@
 #include <errno.h>
 #include "ZendAccelerator.h"
 #include "zend_shared_alloc.h"
+#include "zend_atomic.h"
 #ifdef HAVE_UNISTD_H
 # include <unistd.h>
 #endif
@@ -63,6 +64,14 @@ int lock_file = -1;
 static char lockfile_name[MAXPATHLEN];
 #endif
 
+#ifdef __wasi__
+# ifdef ZTS
+static MUTEX_T zend_shared_alloc_wasi_mutex;
+# else
+static zend_atomic_bool zend_shared_alloc_wasi_lock;
+# endif
+#endif
+
 static const zend_shared_memory_handler_entry handler_table[] = {
 #ifdef USE_MMAP
 	{ "mmap", &zend_alloc_mmap_handlers },
@@ -181,12 +190,18 @@ int zend_shared_alloc_startup(size_t requested_size, size_t reserved_size)
 	smm_shared_globals = &tmp_shared_globals;
 	ZSMMG(shared_free) = requested_size - reserved_size; /* goes to tmp_shared_globals.shared_free */
 
-#ifndef __wasi__
 #ifndef ZEND_WIN32
+#ifdef __wasi__
+#ifdef ZTS
+	zend_shared_alloc_wasi_mutex = tsrm_mutex_alloc();
+#else
+	ZEND_ATOMIC_BOOL_INIT(&zend_shared_alloc_wasi_lock, false);
+#endif
+#else
 	zend_shared_alloc_create_lock(ZCG(accel_directives).lockfile_path);
+#endif
 #else
 	zend_shared_alloc_create_lock();
-#endif
 #endif
 
 	if (ZCG(accel_directives).memory_model && ZCG(accel_directives).memory_model[0]) {
@@ -325,10 +340,17 @@ void zend_shared_alloc_shutdown(void)
 	ZSMMG(shared_segments) = NULL;
 	g_shared_alloc_handler = NULL;
 #ifndef ZEND_WIN32
-	close(lock_file);
+	if (lock_file >= 0) {
+		close(lock_file);
+		lock_file = -1;
+	}
 
 # ifdef ZTS
+#  ifdef __wasi__
+	tsrm_mutex_free(zend_shared_alloc_wasi_mutex);
+#  else
 	tsrm_mutex_free(zts_lock);
+#  endif
 # endif
 #endif
 }
@@ -481,7 +503,14 @@ void zend_shared_alloc_lock(void)
 
 #ifdef ZEND_WIN32
 	zend_shared_alloc_lock_win32();
-#elif !defined(__wasi__)
+#elif defined(__wasi__)
+#ifdef ZTS
+	tsrm_mutex_lock(zend_shared_alloc_wasi_mutex);
+#else
+	while (zend_atomic_bool_exchange_ex(&zend_shared_alloc_wasi_lock, true)) {
+	}
+#endif
+#else
 	struct flock mem_write_lock;
 
 	mem_write_lock.l_type = F_WRLCK;
@@ -531,7 +560,13 @@ void zend_shared_alloc_unlock(void)
 
 #ifdef ZEND_WIN32
 	zend_shared_alloc_unlock_win32();
-#elif !defined(__wasi__)
+#elif defined(__wasi__)
+#ifdef ZTS
+	tsrm_mutex_unlock(zend_shared_alloc_wasi_mutex);
+#else
+	zend_atomic_bool_store_ex(&zend_shared_alloc_wasi_lock, false);
+#endif
+#else
 	if (fcntl(lock_file, F_SETLK, &mem_write_unlock) == -1) {
 		zend_accel_error_noreturn(ACCEL_LOG_ERROR, "Cannot remove lock - %s (%d)", strerror(errno), errno);
 	}