diff --git a/lang/README.md b/lang/README.md
index ee8f1a5..fa595d4 100644
--- a/lang/README.md
+++ b/lang/README.md
@@ -707,40 +707,24 @@ main := fn(): void {
 
 #### very_nested_loops
 ```hb
-$W := 200
-$H := 200
-$MAX_ITER := 20
-$ZOOM := 0.5
+
+$H := 3
+$W := 3
 
 main := fn(): int {
-	mv_x := 0.5
-	mv_y := 0.0
-
-	y := 0
-	loop if y < H break else {
-		x := 0
-		loop if x < W break else {
-			i := MAX_ITER - 1
-
-			c_i := (2.0 * @floatcast(@itf(@as(i32, @intcast(x)))) - @floatcast(@itf(@as(i32, @intcast(W))))) / (W * ZOOM) + mv_x
-			c_r := (2.0 * @floatcast(@itf(@as(i32, @intcast(y)))) - @floatcast(@itf(@as(i32, @intcast(H))))) / (H * ZOOM) + mv_y
-
-			z_i := c_i
-			z_r := c_r
-
-			// iteration
-			loop if (z_r + z_i) * (z_r + z_i) >= 4 | i == 0 break else {
-				// z = z * z + c
-				z_i = z_i * z_i + c_i
-				z_r = z_r * z_r + c_r
-				i -= 1
-			}
-			//   b g r
-			put_pixel(.(x, y), .(@intcast(i), @intcast(i), @intcast(i), 255))
+	y := @as(int, 0)
+	loop if y == H break else {
+		x := @as(int, 0)
+		loop if x == W break else {
+			c_r := @itf(x)
+			c_i := @itf(y)
+			if c_i * c_r >= 10.0 return 0
+			x += 1
 		}
+		y += 1
 	}
 
-	return 0
+	return 1
 }
 
 Color := struct {r: u8, g: u8, b: u8, a: u8}
diff --git a/lang/src/son.rs b/lang/src/son.rs
index 9208ed0..080638e 100644
--- a/lang/src/son.rs
+++ b/lang/src/son.rs
@@ -4844,7 +4844,7 @@ mod tests {
     fn generate(ident: &'static str, input: &'static str, output: &mut String) {
         _ = log::set_logger(&crate::fs::Logger);
         log::set_max_level(log::LevelFilter::Info);
-        //log::set_max_level(log::LevelFilter::Trace);
+        log::set_max_level(log::LevelFilter::Trace);
 
         let mut ctx = CodegenCtx::default();
         let (ref files, embeds) = crate::test_parse_files(ident, input, &mut ctx.parser);
diff --git a/xtask/src/main.rs b/xtask/src/main.rs
index 1c544c2..6e73341 100644
--- a/xtask/src/main.rs
+++ b/xtask/src/main.rs
@@ -25,7 +25,7 @@ fn build_cmd(cmd: impl AsRef<str>) -> std::process::Command {
 }
 
 fn exec(mut cmd: std::process::Command) -> io::Result<()> {
-    if !cmd.status()?.success() {
+    if !cmd.status().inspect_err(|e| println!("failed to execute '{cmd:?}': {e}"))?.success() {
         return Err(io::Error::other(format!("command failed: {:?}", cmd)));
     }
     Ok(())