diff --git a/.github/workflows/on_pull_request.yml b/.github/workflows/on_pull_request.yml
index 21cc5d17795c..0d4cfc2040cd 100644
--- a/.github/workflows/on_pull_request.yml
+++ b/.github/workflows/on_pull_request.yml
@@ -88,6 +88,7 @@ jobs:
               - scripts/ci/*
               - "**/*.html"
               - "**/*.js"
+              - "**/*.mjs"
               - "**/*.json"
               - "**/*.rs"
               - "**/*.toml"
diff --git a/rerun_js/web-viewer/build-wasm.mjs b/rerun_js/web-viewer/build-wasm.mjs
index 70522e6f59b0..38f1da99b377 100644
--- a/rerun_js/web-viewer/build-wasm.mjs
+++ b/rerun_js/web-viewer/build-wasm.mjs
@@ -15,20 +15,26 @@ const exec = (cmd) => {
 };
 
 function buildWebViewer(mode) {
+  let modeFlags = "";
   switch (mode) {
-    case "debug": {
-      return exec(
-        "cargo run -p re_dev_tools -- build-web-viewer --debug --target no-modules-base -o rerun_js/web-viewer",
-      );
-    }
-    case "release": {
-      return exec(
-        "cargo run -p re_dev_tools -- build-web-viewer --release -g --target no-modules-base -o rerun_js/web-viewer",
-      );
-    }
+    case "debug":
+      modeFlags = "--debug";
+      break;
+    case "release":
+      modeFlags = "--release -g";
+      break;
     default:
       throw new Error(`Unknown mode: ${mode}`);
   }
+  return exec(
+    [
+      "cargo run -p re_dev_tools -- build-web-viewer",
+      modeFlags,
+      "--target no-modules-base",
+      "--features map_view,grpc",
+      "-o rerun_js/web-viewer",
+    ].join(" "),
+  );
 }
 
 function re_viewer_js() {