diff --git a/builder/config.go b/builder/config.go
index afada914c..e773ecbf1 100644
--- a/builder/config.go
+++ b/builder/config.go
@@ -26,7 +26,7 @@ func NewConfig(options *compileopts.Options) (*compileopts.Config, error) {
 
 	// Version range supported by TinyGo.
 	const minorMin = 24 // when updating the min version, also update .github/workflows/compat.yml
-	const minorMax = 26
+	const minorMax = 27
 
 	// Check that we support this Go toolchain version.
 	gorootMajor, gorootMinor, err := goenv.GetGorootVersion()
diff --git a/builder/sizes_test.go b/builder/sizes_test.go
index 342d14e1d..fb9193126 100644
--- a/builder/sizes_test.go
+++ b/builder/sizes_test.go
@@ -42,8 +42,8 @@ func TestBinarySize(t *testing.T) {
 	// This is a small number of very diverse targets that we want to test.
 	tests := []sizeTest{
 		// microcontrollers
-		{"hifive1b", "examples/echo", 3771, 309, 0, 2260},
-		{"microbit", "examples/serial", 2832, 368, 8, 2256},
+		{"hifive1b", "examples/echo", 3769, 307, 0, 2260},
+		{"microbit", "examples/serial", 2828, 368, 8, 2256},
 		{"wioterminal", "examples/pininterrupt", 8065, 1663, 132, 7488},
 
 		// TODO: also check wasm. Right now this is difficult, because