diff --git a/conn.go b/conn.go
index 0b6b3fa..ed45ade 100644
--- a/conn.go
+++ b/conn.go
@@ -40,7 +40,7 @@ func OpenFlags(filename string, flags OpenFlag) (conn *Conn, err error) {
 	c := newConn(module)
 	c.ctx = context.Background()
 	namePtr := c.newString(filename)
-	connPtr := c.new(ptrSize)
+	connPtr := c.new(wordSize)
 	defer c.free(namePtr)
 	defer c.free(connPtr)
 
@@ -86,8 +86,8 @@ func (c *Conn) Prepare(sql string) (stmt *Stmt, tail string, err error) {
 
 func (c *Conn) PrepareFlags(sql string, flags PrepareFlag) (stmt *Stmt, tail string, err error) {
 	sqlPtr := c.newString(sql)
-	stmtPtr := c.new(ptrSize)
-	tailPtr := c.new(ptrSize)
+	stmtPtr := c.new(wordSize)
+	tailPtr := c.new(wordSize)
 	defer c.free(sqlPtr)
 	defer c.free(stmtPtr)
 	defer c.free(tailPtr)
@@ -218,4 +218,4 @@ func getString(memory api.Memory, ptr, maxlen uint32) string {
 	}
 }
 
-const ptrSize = 4
+const wordSize = 4
diff --git a/embed/build.sh b/embed/build.sh
index 647c9d8..70d0b3a 100755
--- a/embed/build.sh
+++ b/embed/build.sh
@@ -12,22 +12,7 @@ zig cc --target=wasm32-wasi -flto -g0 -O2 \
 	-mmutable-globals \
 	-mbulk-memory -mreference-types \
 	-mnontrapping-fptoint -msign-ext \
-	-DSQLITE_OS_OTHER=1 -DSQLITE_BYTEORDER=1234 \
-	-DHAVE_ISNAN -DHAVE_USLEEP -DHAVE_MALLOC_USABLE_SIZE \
-	-DSQLITE_DQS=0 \
-	-DSQLITE_THREADSAFE=0 \
-	-DSQLITE_DEFAULT_MEMSTATUS=0 \
-	-DSQLITE_DEFAULT_LOCKING_MODE=1 \
-	-DSQLITE_DEFAULT_WAL_SYNCHRONOUS=1 \
-	-DSQLITE_LIKE_DOESNT_MATCH_BLOBS \
-	-DSQLITE_MAX_EXPR_DEPTH=0 \
-	-DSQLITE_OMIT_DECLTYPE \
-	-DSQLITE_OMIT_DEPRECATED \
-	-DSQLITE_OMIT_PROGRESS_CALLBACK \
-	-DSQLITE_OMIT_SHARED_CACHE \
-	-DSQLITE_OMIT_AUTOINIT \
-	-DSQLITE_OMIT_UTF16 \
-	-DSQLITE_USE_ALLOCA \
+	-D_HAVE_SQLITE_CONFIG_H \
 	-Wl,--export=malloc \
 	-Wl,--export=free \
 	-Wl,--export=malloc_destructor \
diff --git a/sqlite3/main.c b/sqlite3/main.c
index 2f6d24c..b2cf92f 100644
--- a/sqlite3/main.c
+++ b/sqlite3/main.c
@@ -1,4 +1,5 @@
 #include <stdlib.h>
+#include <time.h>
 
 #include "sqlite3.h"
 
@@ -7,6 +8,8 @@ int main() {
   if (rc != SQLITE_OK) return 1;
 }
 
+int go_localtime(sqlite3_int64, struct tm *);
+
 int go_randomness(sqlite3_vfs *, int nByte, char *zOut);
 int go_sleep(sqlite3_vfs *, int microseconds);
 int go_current_time(sqlite3_vfs *, double *);
@@ -48,6 +51,10 @@ static int no_file_control(sqlite3_file *pFile, int op, void *pArg) {
 static int no_sector_size(sqlite3_file *pFile) { return 0; }
 static int no_device_characteristics(sqlite3_file *pFile) { return 0; }
 
+int localtime_s(struct tm *const pTm, time_t const *const pTime) {
+  return go_localtime((sqlite3_int64)*pTime, pTm);
+}
+
 static int go_open_c(sqlite3_vfs *vfs, sqlite3_filename zName,
                      sqlite3_file *file, int flags, int *pOutFlags) {
   static const sqlite3_io_methods go_io = {
diff --git a/sqlite3/sqlite_cfg.h b/sqlite3/sqlite_cfg.h
new file mode 100644
index 0000000..e558235
--- /dev/null
+++ b/sqlite3/sqlite_cfg.h
@@ -0,0 +1,36 @@
+#include <time.h>
+
+// Platform Configuration
+
+#define SQLITE_OS_OTHER 1
+#define SQLITE_BYTEORDER 1234
+
+#define HAVE_ISNAN 1
+#define HAVE_USLEEP 1
+#define HAVE_LOCALTIME_S 1
+#define HAVE_MALLOC_USABLE_SIZE 1
+
+// Recommended Options
+
+#define SQLITE_DQS 0
+#define SQLITE_THREADSAFE 0
+#define SQLITE_DEFAULT_MEMSTATUS 0
+#define SQLITE_DEFAULT_WAL_SYNCHRONOUS 1
+#define SQLITE_LIKE_DOESNT_MATCH_BLOBS
+#define SQLITE_MAX_EXPR_DEPTH 0
+#define SQLITE_OMIT_DECLTYPE
+#define SQLITE_OMIT_DEPRECATED
+#define SQLITE_OMIT_PROGRESS_CALLBACK
+#define SQLITE_OMIT_SHARED_CACHE
+#define SQLITE_OMIT_AUTOINIT
+#define SQLITE_USE_ALLOCA
+
+// Need this to access WAL databases without the use of shared memory.
+#define SQLITE_DEFAULT_LOCKING_MODE 1
+// Go uses UTF-8 everywhere.
+#define SQLITE_OMIT_UTF16
+// Remove some testing code.
+#define SQLITE_UNTESTABLE
+
+// Implemented in Go.
+int localtime_s(struct tm *const pTm, time_t const *const pTime);
\ No newline at end of file
diff --git a/vfs.go b/vfs.go
index cdbe4f7..a3a6582 100644
--- a/vfs.go
+++ b/vfs.go
@@ -26,6 +26,7 @@ func vfsInstantiate(ctx context.Context, r wazero.Runtime) (err error) {
 	}
 
 	env := r.NewHostModuleBuilder("env")
+	env.NewFunctionBuilder().WithFunc(vfsLocaltime).Export("go_localtime")
 	env.NewFunctionBuilder().WithFunc(vfsRandomness).Export("go_randomness")
 	env.NewFunctionBuilder().WithFunc(vfsSleep).Export("go_sleep")
 	env.NewFunctionBuilder().WithFunc(vfsCurrentTime).Export("go_current_time")
@@ -54,6 +55,29 @@ func vfsExit(ctx context.Context, mod api.Module, exitCode uint32) {
 	panic(sys.NewExitError(mod.Name(), exitCode))
 }
 
+func vfsLocaltime(ctx context.Context, mod api.Module, t uint64, pTm uint32) uint32 {
+	tm := time.Unix(int64(t), 0)
+	var isdst int
+	if tm.IsDST() {
+		isdst = 1
+	}
+
+	// https://pubs.opengroup.org/onlinepubs/7908799/xsh/time.h.html
+	if mem := mod.Memory(); true &&
+		mem.WriteUint32Le(pTm+0*wordSize, uint32(tm.Second())) &&
+		mem.WriteUint32Le(pTm+1*wordSize, uint32(tm.Minute())) &&
+		mem.WriteUint32Le(pTm+2*wordSize, uint32(tm.Hour())) &&
+		mem.WriteUint32Le(pTm+3*wordSize, uint32(tm.Day())) &&
+		mem.WriteUint32Le(pTm+4*wordSize, uint32(tm.Month()-time.January)) &&
+		mem.WriteUint32Le(pTm+5*wordSize, uint32(tm.Year()-1900)) &&
+		mem.WriteUint32Le(pTm+6*wordSize, uint32(tm.Weekday()-time.Sunday)) &&
+		mem.WriteUint32Le(pTm+7*wordSize, uint32(tm.YearDay()-1)) &&
+		mem.WriteUint32Le(pTm+8*wordSize, uint32(isdst)) {
+		return _OK
+	}
+	panic(rangeErr)
+}
+
 func vfsRandomness(ctx context.Context, mod api.Module, pVfs, nByte, zByte uint32) uint32 {
 	mem, ok := mod.Memory().Read(zByte, nByte)
 	if !ok {
diff --git a/vfs_files.go b/vfs_files.go
index 656fd89..8b96c18 100644
--- a/vfs_files.go
+++ b/vfs_files.go
@@ -92,7 +92,7 @@ func (p vfsFilePtr) OSFile() *os.File {
 }
 
 func (p vfsFilePtr) ID() uint32 {
-	id, ok := p.Memory().ReadUint32Le(p.ptr + ptrSize)
+	id, ok := p.Memory().ReadUint32Le(p.ptr + wordSize)
 	if !ok {
 		panic(rangeErr)
 	}
@@ -100,7 +100,7 @@ func (p vfsFilePtr) ID() uint32 {
 }
 
 func (p vfsFilePtr) Lock() uint32 {
-	lk, ok := p.Memory().ReadUint32Le(p.ptr + 2*ptrSize)
+	lk, ok := p.Memory().ReadUint32Le(p.ptr + 2*wordSize)
 	if !ok {
 		panic(rangeErr)
 	}
@@ -108,14 +108,14 @@ func (p vfsFilePtr) Lock() uint32 {
 }
 
 func (p vfsFilePtr) SetID(id uint32) vfsFilePtr {
-	if ok := p.Memory().WriteUint32Le(p.ptr+ptrSize, id); !ok {
+	if ok := p.Memory().WriteUint32Le(p.ptr+wordSize, id); !ok {
 		panic(rangeErr)
 	}
 	return p
 }
 
 func (p vfsFilePtr) SetLock(lock uint32) vfsFilePtr {
-	if ok := p.Memory().WriteUint32Le(p.ptr+2*ptrSize, lock); !ok {
+	if ok := p.Memory().WriteUint32Le(p.ptr+2*wordSize, lock); !ok {
 		panic(rangeErr)
 	}
 	return p