diff --git a/README.md b/README.md
index 031a5e8..7f73be2 100644
--- a/README.md
+++ b/README.md
@@ -67,18 +67,14 @@ Performance is tested by running
   - [x] nested transactions
   - [x] incremental BLOB I/O
   - [x] online backup
-  - [ ] snapshots
   - [ ] session extension
-  - [ ] resumable bulk update
-  - [ ] shared-cache mode
-  - [ ] unlock-notify
 - [ ] custom SQL functions
 - [ ] custom VFSes
+  - [ ] in-memory VFS
   - [ ] read-only VFS, wrapping an [`io.ReaderAt`](https://pkg.go.dev/io#ReaderAt)
-  - [ ] in-memory VFS, wrapping a [`bytes.Buffer`](https://pkg.go.dev/bytes#Buffer)
   - [ ] cloud-based VFS, based on [Cloud Backed SQLite](https://sqlite.org/cloudsqlite/doc/trunk/www/index.wiki)
   - [ ] custom VFS API
-  
+
 ### Alternatives
 
 - [`modernc.org/sqlite`](https://pkg.go.dev/modernc.org/sqlite)
diff --git a/embed/build.sh b/embed/build.sh
index f99d560..c0736ec 100755
--- a/embed/build.sh
+++ b/embed/build.sh
@@ -10,5 +10,6 @@ zig cc --target=wasm32-wasi -flto -g0 -O2 \
 	-mmutable-globals \
 	-mbulk-memory -mreference-types \
 	-mnontrapping-fptoint -msign-ext \
+	-mexec-model=reactor \
 	-D_HAVE_SQLITE_CONFIG_H \
 	$(awk '{print "-Wl,--export="$0}' exports.txt)
\ No newline at end of file
diff --git a/embed/sqlite3.wasm b/embed/sqlite3.wasm
index 4353beb..007c8bc 100755
Binary files a/embed/sqlite3.wasm and b/embed/sqlite3.wasm differ
diff --git a/go.mod b/go.mod
index 9310a08..03361db 100644
--- a/go.mod
+++ b/go.mod
@@ -4,7 +4,7 @@ go 1.19
 
 require (
 	github.com/ncruces/julianday v0.1.5
-	github.com/tetratelabs/wazero v1.0.0-rc.2
+	github.com/tetratelabs/wazero v1.0.0
 	golang.org/x/sync v0.1.0
 	golang.org/x/sys v0.6.0
 )
diff --git a/go.sum b/go.sum
index 8b541d0..8200a38 100644
--- a/go.sum
+++ b/go.sum
@@ -1,7 +1,7 @@
 github.com/ncruces/julianday v0.1.5 h1:hDJ9ejiMp3DHsoZ5KW4c1lwfMjbARS7u/gbYcd0FBZk=
 github.com/ncruces/julianday v0.1.5/go.mod h1:Dusn2KvZrrovOMJuOt0TNXL6tB7U2E8kvza5fFc9G7g=
-github.com/tetratelabs/wazero v1.0.0-rc.2 h1:OA3UUynnoqxrjCQ94mpAtdO4/oMxFQVNL2BXDMOc66Q=
-github.com/tetratelabs/wazero v1.0.0-rc.2/go.mod h1:wYx2gNRg8/WihJfSDxA1TIL8H+GkfLYm+bIfbblu9VQ=
+github.com/tetratelabs/wazero v1.0.0 h1:sCE9+mjFex95Ki6hdqwvhyF25x5WslADjDKIFU5BXzI=
+github.com/tetratelabs/wazero v1.0.0/go.mod h1:wYx2gNRg8/WihJfSDxA1TIL8H+GkfLYm+bIfbblu9VQ=
 golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.6.0 h1:MVltZSvRTcU2ljQOhs94SXPftV6DCNnZViHeQps87pQ=
diff --git a/module.go b/module.go
index a742e2d..a3b7a1f 100644
--- a/module.go
+++ b/module.go
@@ -3,14 +3,10 @@ package sqlite3
 
 import (
 	"context"
-	"crypto/rand"
 	"io"
 	"math"
 	"os"
-	"runtime"
-	"strconv"
 	"sync"
-	"sync/atomic"
 
 	"github.com/tetratelabs/wazero"
 	"github.com/tetratelabs/wazero/api"
@@ -28,11 +24,10 @@ var (
 )
 
 var sqlite3 struct {
-	once      sync.Once
-	runtime   wazero.Runtime
-	compiled  wazero.CompiledModule
-	instances atomic.Uint64
-	err       error
+	once     sync.Once
+	runtime  wazero.Runtime
+	compiled wazero.CompiledModule
+	err      error
 }
 
 func instantiateModule() (*module, error) {
@@ -43,12 +38,7 @@ func instantiateModule() (*module, error) {
 		return nil, sqlite3.err
 	}
 
-	name := "sqlite3-" + strconv.FormatUint(sqlite3.instances.Add(1), 10)
-
-	cfg := wazero.NewModuleConfig().WithName(name).
-		WithSysWalltime().WithSysNanotime().WithSysNanosleep().
-		WithOsyield(runtime.Gosched).
-		WithRandSource(rand.Reader)
+	cfg := wazero.NewModuleConfig().WithStartFunctions("_initialize")
 
 	mod, err := sqlite3.runtime.InstantiateModule(ctx, sqlite3.compiled, cfg)
 	if err != nil {
diff --git a/sqlite3/main.c b/sqlite3/main.c
index 755e9e0..657cae9 100644
--- a/sqlite3/main.c
+++ b/sqlite3/main.c
@@ -21,10 +21,8 @@ int sqlite3_os_init() {
   return sqlite3_vfs_register(os_vfs(), /*default=*/true);
 }
 
-int main() {
-  int rc = sqlite3_initialize();
-  if (rc != SQLITE_OK) return 1;
-
+__attribute__((constructor)) void premain() {
+  sqlite3_initialize();
   sqlite3_auto_extension((void (*)(void))sqlite3_base_init);
   sqlite3_auto_extension((void (*)(void))sqlite3_decimal_init);
   sqlite3_auto_extension((void (*)(void))sqlite3_regexp_init);
diff --git a/sqlite3/os.c b/sqlite3/os.c
index 932b90f..46dee16 100644
--- a/sqlite3/os.c
+++ b/sqlite3/os.c
@@ -2,7 +2,7 @@
 
 #include "sqlite3.h"
 
-int os_localtime(sqlite3_int64, struct tm *);
+int os_localtime(struct tm *, sqlite3_int64);
 
 int os_randomness(sqlite3_vfs *, int nByte, char *zOut);
 int os_sleep(sqlite3_vfs *, int microseconds);
@@ -140,5 +140,5 @@ sqlite3_vfs *os_vfs() {
 }
 
 int localtime_s(struct tm *const pTm, time_t const *const pTime) {
-  return os_localtime((sqlite3_int64)*pTime, pTm);
+  return os_localtime(pTm, (sqlite3_int64)*pTime);
 }
diff --git a/tests/mptest/testdata/mptest.wasm b/tests/mptest/testdata/mptest.wasm
index 8e0f152..f8c5650 100755
--- a/tests/mptest/testdata/mptest.wasm
+++ b/tests/mptest/testdata/mptest.wasm
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:eaf30c1ff0cf5acc241c9f7c1ae4c71401ea2be1bd565d67ca913449ef81e542
-size 1630832
+oid sha256:f81ce390812d944d1fa9b2cc607a3629febab0bc0e4473dad3170134509c1751
+size 1630826
diff --git a/tests/speedtest1/testdata/speedtest1.wasm b/tests/speedtest1/testdata/speedtest1.wasm
index b29deb5..cecf3b6 100755
--- a/tests/speedtest1/testdata/speedtest1.wasm
+++ b/tests/speedtest1/testdata/speedtest1.wasm
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:20619ab46d578da689d08c2e6b1d08b7d4919eb7de20f8220bf3a49014083c87
-size 1676135
+oid sha256:0e02a26b86832a4703cd2a86c98ff8041d9d889b865a61f324b512a15d2d361e
+size 1676129
diff --git a/vfs.go b/vfs.go
index e40acfb..eeaed65 100644
--- a/vfs.go
+++ b/vfs.go
@@ -14,19 +14,11 @@ import (
 	"github.com/ncruces/julianday"
 	"github.com/tetratelabs/wazero"
 	"github.com/tetratelabs/wazero/api"
-	"github.com/tetratelabs/wazero/sys"
 )
 
 func vfsInstantiate(ctx context.Context, r wazero.Runtime) {
-	wasi := r.NewHostModuleBuilder("wasi_snapshot_preview1")
-	vfsRegisterFunc(wasi, "proc_exit", vfsExit)
-	_, err := wasi.Instantiate(ctx)
-	if err != nil {
-		panic(err)
-	}
-
 	env := vfsNewEnvModuleBuilder(r)
-	_, err = env.Instantiate(ctx)
+	_, err := env.Instantiate(ctx)
 	if err != nil {
 		panic(err)
 	}
@@ -34,7 +26,7 @@ func vfsInstantiate(ctx context.Context, r wazero.Runtime) {
 
 func vfsNewEnvModuleBuilder(r wazero.Runtime) wazero.HostModuleBuilder {
 	env := r.NewHostModuleBuilder("env")
-	vfsRegisterFunc(env, "os_localtime", vfsLocaltime)
+	vfsRegisterFuncT(env, "os_localtime", vfsLocaltime)
 	vfsRegisterFunc3(env, "os_randomness", vfsRandomness)
 	vfsRegisterFunc2(env, "os_sleep", vfsSleep)
 	vfsRegisterFunc2(env, "os_current_time", vfsCurrentTime)
@@ -46,7 +38,7 @@ func vfsNewEnvModuleBuilder(r wazero.Runtime) wazero.HostModuleBuilder {
 	vfsRegisterFunc1(env, "os_close", vfsClose)
 	vfsRegisterFuncRW(env, "os_read", vfsRead)
 	vfsRegisterFuncRW(env, "os_write", vfsWrite)
-	vfsRegisterFunc(env, "os_truncate", vfsTruncate)
+	vfsRegisterFuncT(env, "os_truncate", vfsTruncate)
 	vfsRegisterFunc2(env, "os_sync", vfsSync)
 	vfsRegisterFunc2(env, "os_file_size", vfsFileSize)
 	vfsRegisterFunc2(env, "os_lock", vfsLock)
@@ -87,14 +79,7 @@ func (vfs *vfsState) Close() error {
 	return nil
 }
 
-func vfsExit(ctx context.Context, mod api.Module, exitCode uint32) {
-	// Ensure other callers see the exit code.
-	_ = mod.CloseWithExitCode(ctx, exitCode)
-	// Prevent any code from executing after this function.
-	panic(sys.NewExitError(mod.Name(), exitCode))
-}
-
-func vfsLocaltime(ctx context.Context, mod api.Module, t uint64, pTm uint32) uint32 {
+func vfsLocaltime(ctx context.Context, mod api.Module, pTm uint32, t uint64) uint32 {
 	tm := time.Unix(int64(t), 0)
 	var isdst int
 	if tm.IsDST() {
@@ -362,10 +347,6 @@ func vfsFileMoved(ctx context.Context, mod api.Module, pFile, pResOut uint32) ui
 	return _OK
 }
 
-func vfsRegisterFunc(mod wazero.HostModuleBuilder, name string, fn any) {
-	mod.NewFunctionBuilder().WithFunc(fn).Export(name)
-}
-
 func vfsRegisterFunc1(mod wazero.HostModuleBuilder, name string, fn func(ctx context.Context, mod api.Module, _ uint32) uint32) {
 	mod.NewFunctionBuilder().
 		WithGoModuleFunction(api.GoModuleFunc(
@@ -425,3 +406,13 @@ func vfsRegisterFuncRW(mod wazero.HostModuleBuilder, name string, fn func(ctx co
 			[]api.ValueType{api.ValueTypeI32, api.ValueTypeI32, api.ValueTypeI32, api.ValueTypeI64}, []api.ValueType{api.ValueTypeI32}).
 		Export(name)
 }
+
+func vfsRegisterFuncT(mod wazero.HostModuleBuilder, name string, fn func(ctx context.Context, mod api.Module, _ uint32, _ uint64) uint32) {
+	mod.NewFunctionBuilder().
+		WithGoModuleFunction(api.GoModuleFunc(
+			func(ctx context.Context, mod api.Module, stack []uint64) {
+				stack[0] = uint64(fn(ctx, mod, uint32(stack[0]), stack[1]))
+			}),
+			[]api.ValueType{api.ValueTypeI32, api.ValueTypeI64}, []api.ValueType{api.ValueTypeI32}).
+		Export(name)
+}
diff --git a/vfs_test.go b/vfs_test.go
index e8770c9..881e11b 100644
--- a/vfs_test.go
+++ b/vfs_test.go
@@ -14,19 +14,11 @@ import (
 	"github.com/ncruces/julianday"
 )
 
-func Test_vfsExit(t *testing.T) {
-	mem := newMemory(128)
-	ctx := context.TODO()
-	defer func() { _ = recover() }()
-	vfsExit(ctx, mem.mod, 1)
-	t.Error("want panic")
-}
-
 func Test_vfsLocaltime(t *testing.T) {
 	mem := newMemory(128)
 	ctx := context.TODO()
 
-	rc := vfsLocaltime(ctx, mem.mod, 0, 4)
+	rc := vfsLocaltime(ctx, mem.mod, 4, 0)
 	if rc != 0 {
 		t.Fatal("returned", rc)
 	}