diff --git a/doc/DESIGN.md b/doc/DESIGN.md
index 6661f10..67a40e2 100644
--- a/doc/DESIGN.md
+++ b/doc/DESIGN.md
@@ -68,9 +68,9 @@ bkt/
 				snapshots/                    # snapshots w/ timestamp+offset
 					20000101T000000Z-000000000000023.snapshot
 				wal/                          # compressed WAL files
-					000000000000001-0.wal.gz    
-					000000000000001-<offset>.wal.gz
-					000000000000002-0.wal.gz
+					000000000000001-0.wal.lz4    
+					000000000000001-<offset>.wal.lz4
+					000000000000002-0.wal.lz4
 		00000002/
 			snapshot/
 				000000000000000.snapshot
@@ -82,7 +82,7 @@ bkt/
 						20000101T000000Z-000000000000023.snapshot
 
 			wal/
-				000000000000001.wal.gz
+				000000000000001.wal.lz4
 ```
 
 
diff --git a/go.mod b/go.mod
index 4e8ab2c..127151a 100644
--- a/go.mod
+++ b/go.mod
@@ -6,6 +6,7 @@ require (
 	github.com/aws/aws-sdk-go v1.27.0
 	github.com/davecgh/go-spew v1.1.1
 	github.com/mattn/go-sqlite3 v1.14.5
+	github.com/pierrec/lz4/v4 v4.1.3
 	github.com/prometheus/client_golang v1.9.0
 	gopkg.in/yaml.v2 v2.4.0
 )
diff --git a/go.sum b/go.sum
index 40988cd..3793bf7 100644
--- a/go.sum
+++ b/go.sum
@@ -197,7 +197,11 @@ github.com/pascaldekloe/goe v0.0.0-20180627143212-57f6aae5913c/go.mod h1:lzWF7FI
 github.com/pborman/uuid v1.2.0/go.mod h1:X/NO0urCmaxf9VXbdlT7C2Yzkj2IKimNn4k+gtPdI/k=
 github.com/performancecopilot/speed v3.0.0+incompatible/go.mod h1:/CLtqpZ5gBg1M9iaPbIdPPGyKcA8hKdoy6hAWba7Yac=
 github.com/pierrec/lz4 v1.0.2-0.20190131084431-473cd7ce01a1/go.mod h1:3/3N9NVKO0jef7pBehbT1qWhCMrIgbYNnFAZCqQ5LRc=
+github.com/pierrec/lz4 v2.0.5+incompatible h1:2xWsjqPFWcplujydGg4WmhC/6fZqK42wMM8aXeqhl0I=
 github.com/pierrec/lz4 v2.0.5+incompatible/go.mod h1:pdkljMzZIN41W+lC3N2tnIh5sFi+IEE17M5jbnwPHcY=
+github.com/pierrec/lz4 v2.6.0+incompatible h1:Ix9yFKn1nSPBLFl/yZknTp8TU5G4Ps0JDmguYK6iH1A=
+github.com/pierrec/lz4/v4 v4.1.3 h1:/dvQpkb0o1pVlSgKNQqfkavlnXaIK+hJ0LXsKRUN9D4=
+github.com/pierrec/lz4/v4 v4.1.3/go.mod h1:gZWDp/Ze/IJXGXf23ltt2EXimqmTUXEy0GFuRQyBid4=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
diff --git a/litestream.go b/litestream.go
index 0321124..98c89ed 100644
--- a/litestream.go
+++ b/litestream.go
@@ -219,7 +219,7 @@ func ParseSnapshotPath(s string) (index int, ext string, err error) {
 	return int(i64), a[2], nil
 }
 
-var snapshotPathRegex = regexp.MustCompile(`^([0-9a-f]{8})(.snapshot(?:.gz)?)$`)
+var snapshotPathRegex = regexp.MustCompile(`^([0-9a-f]{8})(.snapshot(?:.lz4)?)$`)
 
 // IsWALPath returns true if s is a path to a WAL file.
 func IsWALPath(s string) bool {
@@ -254,7 +254,7 @@ func FormatWALPathWithOffset(index int, offset int64) string {
 	return fmt.Sprintf("%08x_%08x%s", index, offset, WALExt)
 }
 
-var walPathRegex = regexp.MustCompile(`^([0-9a-f]{8})(?:_([0-9a-f]{8}))?(.wal(?:.gz)?)$`)
+var walPathRegex = regexp.MustCompile(`^([0-9a-f]{8})(?:_([0-9a-f]{8}))?(.wal(?:.lz4)?)$`)
 
 // isHexChar returns true if ch is a lowercase hex character.
 func isHexChar(ch rune) bool {
diff --git a/replica.go b/replica.go
index 6253e4f..495ea1d 100644
--- a/replica.go
+++ b/replica.go
@@ -1,7 +1,6 @@
 package litestream
 
 import (
-	"compress/gzip"
 	"context"
 	"fmt"
 	"io"
@@ -15,6 +14,7 @@ import (
 	"time"
 
 	"github.com/benbjohnson/litestream/internal"
+	"github.com/pierrec/lz4/v4"
 	"github.com/prometheus/client_golang/prometheus"
 )
 
@@ -176,7 +176,7 @@ func (r *FileReplica) SnapshotDir(generation string) string {
 
 // SnapshotPath returns the path to a snapshot file.
 func (r *FileReplica) SnapshotPath(generation string, index int) string {
-	return filepath.Join(r.SnapshotDir(generation), fmt.Sprintf("%08x.snapshot.gz", index))
+	return filepath.Join(r.SnapshotDir(generation), fmt.Sprintf("%08x.snapshot.lz4", index))
 }
 
 // MaxSnapshotIndex returns the highest index for the snapshots.
@@ -622,7 +622,7 @@ func (r *FileReplica) Sync(ctx context.Context) (err error) {
 		}
 	}
 
-	// Gzip any old WAL files.
+	// Compress any old WAL files.
 	if generation != "" {
 		if err := r.compress(ctx, generation); err != nil {
 			return fmt.Errorf("cannot compress: %s", err)
@@ -683,7 +683,7 @@ func (r *FileReplica) syncWAL(ctx context.Context) (err error) {
 	return nil
 }
 
-// compress gzips all WAL files before the current one.
+// compress compresses all WAL files before the current one.
 func (r *FileReplica) compress(ctx context.Context, generation string) error {
 	filenames, err := filepath.Glob(filepath.Join(r.WALDir(generation), "**/*.wal"))
 	if err != nil {
@@ -704,7 +704,7 @@ func (r *FileReplica) compress(ctx context.Context, generation string) error {
 		default:
 		}
 
-		dst := filename + ".gz"
+		dst := filename + ".lz4"
 		if err := compressFile(filename, dst, r.db.uid, r.db.gid); err != nil {
 			return err
 		} else if err := os.Remove(filename); err != nil {
@@ -738,16 +738,11 @@ func (r *FileReplica) SnapshotReader(ctx context.Context, generation string, ind
 		} else if ext == ".snapshot" {
 			return f, nil // not compressed, return as-is.
 		}
-		assert(ext == ".snapshot.gz", "invalid snapshot extension")
+		assert(ext == ".snapshot.lz4", "invalid snapshot extension")
 
-		// If compressed, wrap in a gzip reader and return with wrapper to
+		// If compressed, wrap in an lz4 reader and return with wrapper to
 		// ensure that the underlying file is closed.
-		r, err := gzip.NewReader(f)
-		if err != nil {
-			f.Close()
-			return nil, err
-		}
-		return internal.NewReadCloser(r, f), nil
+		return internal.NewReadCloser(lz4.NewReader(f), f), nil
 	}
 	return nil, os.ErrNotExist
 }
@@ -766,19 +761,14 @@ func (r *FileReplica) WALReader(ctx context.Context, generation string, index in
 	}
 
 	// Otherwise read the compressed file. Return error if file doesn't exist.
-	f, err = os.Open(filename + ".gz")
+	f, err = os.Open(filename + ".lz4")
 	if err != nil {
 		return nil, err
 	}
 
-	// If compressed, wrap in a gzip reader and return with wrapper to
+	// If compressed, wrap in an lz4 reader and return with wrapper to
 	// ensure that the underlying file is closed.
-	rd, err := gzip.NewReader(f)
-	if err != nil {
-		f.Close()
-		return nil, err
-	}
-	return internal.NewReadCloser(rd, f), nil
+	return internal.NewReadCloser(lz4.NewReader(f), f), nil
 }
 
 // EnforceRetention forces a new snapshot once the retention interval has passed.
@@ -950,7 +940,7 @@ func WALIndexAt(ctx context.Context, r Replica, generation string, maxIndex int,
 	return index, nil
 }
 
-// compressFile compresses a file and replaces it with a new file with a .gz extension.
+// compressFile compresses a file and replaces it with a new file with a .lz4 extension.
 func compressFile(src, dst string, uid, gid int) error {
 	r, err := os.Open(src)
 	if err != nil {
@@ -964,13 +954,13 @@ func compressFile(src, dst string, uid, gid int) error {
 	}
 	defer w.Close()
 
-	gz := gzip.NewWriter(w)
-	defer gz.Close()
+	zr := lz4.NewWriter(w)
+	defer zr.Close()
 
 	// Copy & compress file contents to temporary file.
-	if _, err := io.Copy(gz, r); err != nil {
+	if _, err := io.Copy(zr, r); err != nil {
 		return err
-	} else if err := gz.Close(); err != nil {
+	} else if err := zr.Close(); err != nil {
 		return err
 	} else if err := w.Sync(); err != nil {
 		return err
diff --git a/s3/s3.go b/s3/s3.go
index 60b8634..becfb67 100644
--- a/s3/s3.go
+++ b/s3/s3.go
@@ -2,7 +2,6 @@ package s3
 
 import (
 	"bytes"
-	"compress/gzip"
 	"context"
 	"fmt"
 	"io"
@@ -20,6 +19,7 @@ import (
 	"github.com/aws/aws-sdk-go/service/s3/s3manager"
 	"github.com/benbjohnson/litestream"
 	"github.com/benbjohnson/litestream/internal"
+	"github.com/pierrec/lz4/v4"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
 )
@@ -155,7 +155,7 @@ func (r *Replica) SnapshotDir(generation string) string {
 
 // SnapshotPath returns the path to a snapshot file.
 func (r *Replica) SnapshotPath(generation string, index int) string {
-	return path.Join(r.SnapshotDir(generation), fmt.Sprintf("%08x.snapshot.gz", index))
+	return path.Join(r.SnapshotDir(generation), fmt.Sprintf("%08x.snapshot.lz4", index))
 }
 
 // MaxSnapshotIndex returns the highest index for the snapshots.
@@ -588,13 +588,13 @@ func (r *Replica) snapshot(ctx context.Context, generation string, index int) er
 	}
 
 	pr, pw := io.Pipe()
-	gw := gzip.NewWriter(pw)
+	zw := lz4.NewWriter(pw)
 	go func() {
-		if _, err := io.Copy(gw, f); err != nil {
+		if _, err := io.Copy(zw, f); err != nil {
 			_ = pw.CloseWithError(err)
 			return
 		}
-		_ = pw.CloseWithError(gw.Close())
+		_ = pw.CloseWithError(zw.Close())
 	}()
 
 	snapshotPath := r.SnapshotPath(generation, index)
@@ -770,11 +770,11 @@ func (r *Replica) syncWAL(ctx context.Context) (err error) {
 	}
 
 	var buf bytes.Buffer
-	gw := gzip.NewWriter(&buf)
-	n, err := gw.Write(b)
+	zw := lz4.NewWriter(&buf)
+	n, err := zw.Write(b)
 	if err != nil {
 		return err
-	} else if err := gw.Close(); err != nil {
+	} else if err := zw.Close(); err != nil {
 		return err
 	}
 
@@ -782,7 +782,7 @@ func (r *Replica) syncWAL(ctx context.Context) (err error) {
 	// that files are contiguous without having to decompress.
 	walPath := path.Join(
 		r.WALDir(rd.Pos().Generation),
-		litestream.FormatWALPathWithOffset(pos.Index, pos.Offset)+".gz",
+		litestream.FormatWALPathWithOffset(pos.Index, pos.Offset)+".lz4",
 	)
 
 	if _, err := r.uploader.UploadWithContext(ctx, &s3manager.UploadInput{
@@ -826,12 +826,7 @@ func (r *Replica) SnapshotReader(ctx context.Context, generation string, index i
 	r.getOperationBytesCounter.Add(float64(*out.ContentLength))
 
 	// Decompress the snapshot file.
-	gr, err := gzip.NewReader(out.Body)
-	if err != nil {
-		out.Body.Close()
-		return nil, err
-	}
-	return internal.NewReadCloser(gr, out.Body), nil
+	return internal.NewReadCloser(lz4.NewReader(out.Body), out.Body), nil
 }
 
 // WALReader returns a reader for WAL data at the given index.
@@ -886,13 +881,9 @@ func (r *Replica) WALReader(ctx context.Context, generation string, index int) (
 		r.getOperationTotalCounter.Inc()
 		r.getOperationTotalCounter.Add(float64(*out.ContentLength))
 
-		gr, err := gzip.NewReader(out.Body)
-		if err != nil {
-			return nil, err
-		}
-		defer gr.Close()
+		zr := lz4.NewReader(out.Body)
 
-		n, err := io.Copy(&buf, gr)
+		n, err := io.Copy(&buf, zr)
 		if err != nil {
 			return nil, err
 		}