diff --git a/cmd/tsconnect/build-pkg.go b/cmd/tsconnect/build-pkg.go
index e0220b42f..8b0b6a79b 100644
--- a/cmd/tsconnect/build-pkg.go
+++ b/cmd/tsconnect/build-pkg.go
@@ -12,6 +12,7 @@ import (
 	"path"
 
 	"github.com/tailscale/hujson"
+	"tailscale.com/util/precompress"
 	"tailscale.com/version"
 )
 
@@ -37,6 +38,10 @@ func runBuildPkg() {
 
 	runEsbuild(*buildOptions)
 
+	if err := precompressWasm(); err != nil {
+		log.Fatalf("Could not pre-recompress wasm: %v", err)
+	}
+
 	log.Printf("Generating types...\n")
 	if err := runYarn("pkg-types"); err != nil {
 		log.Fatalf("Type generation failed: %v", err)
@@ -49,6 +54,13 @@ func runBuildPkg() {
 	log.Printf("Built package version %s", version.Long)
 }
 
+func precompressWasm() error {
+	log.Printf("Pre-compressing main.wasm...\n")
+	return precompress.Precompress(path.Join(*pkgDir, "main.wasm"), precompress.Options{
+		FastCompression: *fastCompression,
+	})
+}
+
 func updateVersion() error {
 	packageJSONBytes, err := os.ReadFile("package.json.tmpl")
 	if err != nil {
diff --git a/util/precompress/precompress.go b/util/precompress/precompress.go
index e5caeca13..32181dffa 100644
--- a/util/precompress/precompress.go
+++ b/util/precompress/precompress.go
@@ -42,7 +42,7 @@ func PrecompressDir(dirPath string, options Options) error {
 		}
 
 		eg.Go(func() error {
-			return precompress(p, options)
+			return Precompress(p, options)
 		})
 		return nil
 	})
@@ -81,12 +81,11 @@ func OpenPrecompressedFile(w http.ResponseWriter, r *http.Request, path string,
 }
 
 var compressibleExtensions = map[string]bool{
-	".js":   true,
-	".css":  true,
-	".wasm": true,
+	".js":  true,
+	".css": true,
 }
 
-func precompress(path string, options Options) error {
+func Precompress(path string, options Options) error {
 	contents, err := os.ReadFile(path)
 	if err != nil {
 		return err