diff --git a/packages/squiggle-lang/src/js/index.ts b/packages/squiggle-lang/src/js/index.ts
index 5e4cf2c1..acee005c 100644
--- a/packages/squiggle-lang/src/js/index.ts
+++ b/packages/squiggle-lang/src/js/index.ts
@@ -120,77 +120,86 @@ function createTsExport(
   x: expressionValue,
   environment: environment
 ): squiggleExpression {
-  switch (x.tag) {
-    case "EvArray":
-      // genType doesn't convert anything more than 2 layers down into {tag: x, value: x}
-      // format, leaving it as the raw values. This converts the raw values
-      // directly into typescript values.
-      //
-      // The casting here is because genType is about the types of the returned
-      // values, claiming they are fully recursive when that's not actually the
-      // case
-      return tag(
-        "array",
-        x.value.map(
-          (arrayItem): squiggleExpression =>
-            convertRawToTypescript(
-              arrayItem as unknown as rescriptExport,
-              environment
+  switch (x) {
+    case "EvVoid":
+      return tag("void", "");
+    default: {
+      switch (x.tag) {
+        case "EvArray":
+          // genType doesn't convert anything more than 2 layers down into {tag: x, value: x}
+          // format, leaving it as the raw values. This converts the raw values
+          // directly into typescript values.
+          //
+          // The casting here is because genType is about the types of the returned
+          // values, claiming they are fully recursive when that's not actually the
+          // case
+          return tag(
+            "array",
+            x.value.map(
+              (arrayItem): squiggleExpression =>
+                convertRawToTypescript(
+                  arrayItem as unknown as rescriptExport,
+                  environment
+                )
             )
-        )
-      );
-    case "EvArrayString":
-      return tag("arraystring", x.value);
-    case "EvBool":
-      return tag("boolean", x.value);
-    case "EvCall":
-      return tag("call", x.value);
-    case "EvLambda":
-      return tag("lambda", x.value);
-    case "EvDistribution":
-      return tag("distribution", new Distribution(x.value, environment));
-    case "EvNumber":
-      return tag("number", x.value);
-    case "EvRecord":
-      // genType doesn't support records, so we have to do the raw conversion ourself
-      let result: tagged<"record", { [key: string]: squiggleExpression }> = tag(
-        "record",
-        _.mapValues(x.value, (x: unknown) =>
-          convertRawToTypescript(x as rescriptExport, environment)
-        )
-      );
-      return result;
-    case "EvString":
-      return tag("string", x.value);
-    case "EvSymbol":
-      return tag("symbol", x.value);
-    case "EvDate":
-      return tag("date", x.value);
-    case "EvTimeDuration":
-      return tag("timeDuration", x.value);
-    case "EvDeclaration":
-      return tag("lambdaDeclaration", x.value);
-    case "EvTypeIdentifier":
-      return tag("typeIdentifier", x.value);
-    case "EvType":
-      let typeResult: tagged<"type", { [key: string]: squiggleExpression }> =
-        tag(
-          "type",
-          _.mapValues(x.value, (x: unknown) =>
-            convertRawToTypescript(x as rescriptExport, environment)
-          )
-        );
-      return typeResult;
-    case "EvModule":
-      let moduleResult: tagged<
-        "module",
-        { [key: string]: squiggleExpression }
-      > = tag(
-        "module",
-        _.mapValues(x.value, (x: unknown) =>
-          convertRawToTypescript(x as rescriptExport, environment)
-        )
-      );
-      return moduleResult;
+          );
+        case "EvArrayString":
+          return tag("arraystring", x.value);
+        case "EvBool":
+          return tag("boolean", x.value);
+        case "EvCall":
+          return tag("call", x.value);
+        case "EvLambda":
+          return tag("lambda", x.value);
+        case "EvDistribution":
+          return tag("distribution", new Distribution(x.value, environment));
+        case "EvNumber":
+          return tag("number", x.value);
+        case "EvRecord":
+          // genType doesn't support records, so we have to do the raw conversion ourself
+          let result: tagged<"record", { [key: string]: squiggleExpression }> =
+            tag(
+              "record",
+              _.mapValues(x.value, (x: unknown) =>
+                convertRawToTypescript(x as rescriptExport, environment)
+              )
+            );
+          return result;
+        case "EvString":
+          return tag("string", x.value);
+        case "EvSymbol":
+          return tag("symbol", x.value);
+        case "EvDate":
+          return tag("date", x.value);
+        case "EvTimeDuration":
+          return tag("timeDuration", x.value);
+        case "EvDeclaration":
+          return tag("lambdaDeclaration", x.value);
+        case "EvTypeIdentifier":
+          return tag("typeIdentifier", x.value);
+        case "EvType":
+          let typeResult: tagged<
+            "type",
+            { [key: string]: squiggleExpression }
+          > = tag(
+            "type",
+            _.mapValues(x.value, (x: unknown) =>
+              convertRawToTypescript(x as rescriptExport, environment)
+            )
+          );
+          return typeResult;
+        case "EvModule":
+          let moduleResult: tagged<
+            "module",
+            { [key: string]: squiggleExpression }
+          > = tag(
+            "module",
+            _.mapValues(x.value, (x: unknown) =>
+              convertRawToTypescript(x as rescriptExport, environment)
+            )
+          );
+          return moduleResult;
+      }
+    }
   }
 }
diff --git a/packages/squiggle-lang/src/js/rescript_interop.ts b/packages/squiggle-lang/src/js/rescript_interop.ts
index dcba24e6..80548a7f 100644
--- a/packages/squiggle-lang/src/js/rescript_interop.ts
+++ b/packages/squiggle-lang/src/js/rescript_interop.ts
@@ -131,7 +131,8 @@ export type squiggleExpression =
   | tagged<"record", { [key: string]: squiggleExpression }>
   | tagged<"type", { [key: string]: squiggleExpression }>
   | tagged<"typeIdentifier", string>
-  | tagged<"module", { [key: string]: squiggleExpression }>;
+  | tagged<"module", { [key: string]: squiggleExpression }>
+  | tagged<"void", string>;
 
 export { lambdaValue };