diff --git a/compiler/test_gen/src/gen_num.rs b/compiler/test_gen/src/gen_num.rs
index 88480c6310..11ae54b991 100644
--- a/compiler/test_gen/src/gen_num.rs
+++ b/compiler/test_gen/src/gen_num.rs
@@ -2745,6 +2745,130 @@ fn num_to_str() {
     );
 }
 
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_u8() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr 0u8"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1u8"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10u8"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", u8::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxU8"#, RocStr::from(max.as_str()), RocStr);
+}
+
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_u16() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr 0u16"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1u16"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10u16"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", u16::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxU16"#, RocStr::from(max.as_str()), RocStr);
+}
+
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_u32() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr 0u32"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1u32"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10u32"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", u32::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxU32"#, RocStr::from(max.as_str()), RocStr);
+}
+
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_u64() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr 0u64"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1u64"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10u64"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", u64::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxU64"#, RocStr::from(max.as_str()), RocStr);
+}
+
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_i8() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr -10i8"#, RocStr::from("-10"), RocStr);
+    assert_evals_to!(r#"Num.toStr -1i8"#, RocStr::from("-1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 0i8"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1i8"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10i8"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", i8::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxI8"#, RocStr::from(max.as_str()), RocStr);
+
+    let max = format!("{}", i8::MIN);
+    assert_evals_to!(r#"Num.toStr Num.minI8"#, RocStr::from(max.as_str()), RocStr);
+}
+
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_i16() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr -10i16"#, RocStr::from("-10"), RocStr);
+    assert_evals_to!(r#"Num.toStr -1i16"#, RocStr::from("-1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 0i16"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1i16"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10i16"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", i16::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxI16"#, RocStr::from(max.as_str()), RocStr);
+
+    let max = format!("{}", i16::MIN);
+    assert_evals_to!(r#"Num.toStr Num.minI16"#, RocStr::from(max.as_str()), RocStr);
+}
+
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_i32() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr -10i32"#, RocStr::from("-10"), RocStr);
+    assert_evals_to!(r#"Num.toStr -1i32"#, RocStr::from("-1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 0i32"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1i32"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10i32"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", i32::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxI32"#, RocStr::from(max.as_str()), RocStr);
+
+    let max = format!("{}", i32::MIN);
+    assert_evals_to!(r#"Num.toStr Num.minI32"#, RocStr::from(max.as_str()), RocStr);
+}
+
+#[test]
+#[cfg(any(feature = "gen-llvm"))]
+fn num_to_str_i64() {
+    use roc_std::RocStr;
+
+    assert_evals_to!(r#"Num.toStr -10i64"#, RocStr::from("-10"), RocStr);
+    assert_evals_to!(r#"Num.toStr -1i64"#, RocStr::from("-1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 0i64"#, RocStr::from("0"), RocStr);
+    assert_evals_to!(r#"Num.toStr 1i64"#, RocStr::from("1"), RocStr);
+    assert_evals_to!(r#"Num.toStr 10i64"#, RocStr::from("10"), RocStr);
+
+    let max = format!("{}", i64::MAX);
+    assert_evals_to!(r#"Num.toStr Num.maxI64"#, RocStr::from(max.as_str()), RocStr);
+
+    let max = format!("{}", i64::MIN);
+    assert_evals_to!(r#"Num.toStr Num.minI64"#, RocStr::from(max.as_str()), RocStr);
+}
+
 #[test]
 #[cfg(any(feature = "gen-llvm", feature = "gen-wasm"))]
 fn u8_addition_greater_than_i8() {