diff --git a/packages/squiggle-lang/src/rescript/ForTS/ForTS_Result.res b/packages/squiggle-lang/src/rescript/ForTS/ForTS_Result.res
index 19bf6ee0..7ace5c9c 100644
--- a/packages/squiggle-lang/src/rescript/ForTS/ForTS_Result.res
+++ b/packages/squiggle-lang/src/rescript/ForTS/ForTS_Result.res
@@ -16,3 +16,16 @@ let getValue = (r: result_<'a, 'e>): option<'a> =>
   | Ok(v) => Some(v)
   | Error(_) => None
   }
+
+@module("ForTS_Result_tag") @scope("ResultTag")
+external rtOk_: int = "RtOk"
+
+@module("ForTS_Result_tag") @scope("ResultTag")
+external rtError_: int = "RtError"
+
+@genType
+let getTag = (r: result_<'a, 'e>): int =>
+  switch r {
+  | Ok(_) => rtOk_
+  | Error(_) => rtError_
+  }
diff --git a/packages/squiggle-lang/src/rescript/ForTS/ForTS_Result_tag.ts b/packages/squiggle-lang/src/rescript/ForTS/ForTS_Result_tag.ts
new file mode 100644
index 00000000..571de93a
--- /dev/null
+++ b/packages/squiggle-lang/src/rescript/ForTS/ForTS_Result_tag.ts
@@ -0,0 +1,4 @@
+enum ResultTag {
+    Ok,
+    Error,
+}
\ No newline at end of file