diff --git a/hosts/javascript/platform.py b/hosts/javascript/platform.py
index 92fb08d..2605f52 100644
--- a/hosts/javascript/platform.py
+++ b/hosts/javascript/platform.py
@@ -1175,17 +1175,6 @@ PRIMITIVES_JS_MODULES: dict[str, str] = {
     lst[idx] = val;
     return NIL;
   };
-  // Cookie access — isomorphic state persistence
-  PRIMITIVES["set-cookie"] = function(name, value, days) {
-    var d = days || 365;
-    var expires = new Date(Date.now() + d * 864e5).toUTCString();
-    document.cookie = name + "=" + encodeURIComponent(value) + ";expires=" + expires + ";path=/;SameSite=Lax";
-    return NIL;
-  };
-  PRIMITIVES["get-cookie"] = function(name) {
-    var m = document.cookie.match(new RegExp("(?:^|;\\\\s*)" + name + "=([^;]*)"));
-    return m ? decodeURIComponent(m[1]) : NIL;
-  };
 
   PRIMITIVES["env-parent"] = function(env) {
     if (env && Object.getPrototypeOf(env) !== Object.prototype &&
@@ -1734,20 +1723,6 @@ CEK_FIXUPS_JS = '''
   PRIMITIVES["is-html-tag?"] = function(n) { return HTML_TAGS.indexOf(n) >= 0; };
   function makeEnv() { return merge(componentEnv, PRIMITIVES); }
   PRIMITIVES["make-env"] = makeEnv;
-
-  // localStorage — defined here (before boot) so islands can use at hydration
-  PRIMITIVES["local-storage-get"] = function(key) {
-    try { var v = localStorage.getItem(key); return v === null ? NIL : v; }
-    catch (e) { return NIL; }
-  };
-  PRIMITIVES["local-storage-set"] = function(key, val) {
-    try { localStorage.setItem(key, val); } catch (e) {}
-    return NIL;
-  };
-  PRIMITIVES["local-storage-remove"] = function(key) {
-    try { localStorage.removeItem(key); } catch (e) {}
-    return NIL;
-  };
 '''
 
 
@@ -3223,127 +3198,18 @@ def fixups_js(has_html, has_sx, has_dom, has_signals=False, has_deps=False, has_
     return _rawCallLambda(f, args, callerEnv);
   };
 
-  // Expose render functions as primitives so SX code can call them''']
-    if has_html:
-        lines.append('  if (typeof renderToHtml === "function") PRIMITIVES["render-to-html"] = renderToHtml;')
-    if has_sx:
-        lines.append('  if (typeof renderToSx === "function") PRIMITIVES["render-to-sx"] = renderToSx;')
-        lines.append('  if (typeof aser === "function") PRIMITIVES["aser"] = aser;')
-    if has_dom:
-        lines.append('  if (typeof renderToDom === "function") PRIMITIVES["render-to-dom"] = renderToDom;')
-    if has_signals:
-        lines.append('''
-  // Expose signal functions as primitives so runtime-evaluated SX code
-  // (e.g. island bodies from .sx files) can call them
-  PRIMITIVES["signal"] = signal;
-  PRIMITIVES["signal?"] = isSignal;
-  PRIMITIVES["deref"] = deref;
-  PRIMITIVES["reset!"] = reset_b;
-  PRIMITIVES["swap!"] = swap_b;
-  PRIMITIVES["computed"] = computed;
-  PRIMITIVES["effect"] = effect;
-  PRIMITIVES["batch"] = batch;
-  // Timer primitives for island code
-  PRIMITIVES["set-interval"] = setInterval_;
-  PRIMITIVES["clear-interval"] = clearInterval_;
-  // Reactive DOM helpers for island code
-  PRIMITIVES["reactive-text"] = reactiveText;
-  PRIMITIVES["create-text-node"] = createTextNode;
-  PRIMITIVES["dom-set-text-content"] = domSetTextContent;
-  PRIMITIVES["dom-listen"] = domListen;
-  PRIMITIVES["dom-dispatch"] = domDispatch;
-  PRIMITIVES["event-detail"] = eventDetail;
-  PRIMITIVES["resource"] = resource;
-  PRIMITIVES["promise-delayed"] = promiseDelayed;
-  PRIMITIVES["promise-then"] = promiseThen;
-  PRIMITIVES["def-store"] = defStore;
-  PRIMITIVES["use-store"] = useStore;
-  PRIMITIVES["emit-event"] = emitEvent;
-  PRIMITIVES["on-event"] = onEvent;
-  PRIMITIVES["bridge-event"] = bridgeEvent;
-  // DOM primitives for island code
-  PRIMITIVES["dom-focus"] = domFocus;
-  PRIMITIVES["dom-tag-name"] = domTagName;
-  PRIMITIVES["dom-get-prop"] = domGetProp;
-  PRIMITIVES["dom-set-prop"] = domSetProp;
-  PRIMITIVES["dom-call-method"] = domCallMethod;
-  PRIMITIVES["dom-post-message"] = domPostMessage;
-  PRIMITIVES["stop-propagation"] = stopPropagation_;
-  PRIMITIVES["error-message"] = errorMessage;
-  PRIMITIVES["schedule-idle"] = scheduleIdle;
-  PRIMITIVES["error"] = function(msg) { throw new Error(msg); };
-  PRIMITIVES["filter"] = filter;
-  // DOM primitives for sx-on:* handlers and data-init scripts
-  if (typeof domBody === "function") PRIMITIVES["dom-body"] = domBody;
-  if (typeof domQuery === "function") PRIMITIVES["dom-query"] = domQuery;
-  if (typeof domQueryAll === "function") PRIMITIVES["dom-query-all"] = domQueryAll;
-  if (typeof domQueryById === "function") PRIMITIVES["dom-query-by-id"] = domQueryById;
-  if (typeof domSetAttr === "function") PRIMITIVES["dom-set-attr"] = domSetAttr;
-  if (typeof domGetAttr === "function") PRIMITIVES["dom-get-attr"] = domGetAttr;
-  if (typeof domRemoveAttr === "function") PRIMITIVES["dom-remove-attr"] = domRemoveAttr;
-  if (typeof domHasAttr === "function") PRIMITIVES["dom-has-attr?"] = domHasAttr;
-  if (typeof domAddClass === "function") PRIMITIVES["dom-add-class"] = domAddClass;
-  if (typeof domRemoveClass === "function") PRIMITIVES["dom-remove-class"] = domRemoveClass;
-  if (typeof domHasClass === "function") PRIMITIVES["dom-has-class?"] = domHasClass;
-  if (typeof domClosest === "function") PRIMITIVES["dom-closest"] = domClosest;
-  if (typeof domMatches === "function") PRIMITIVES["dom-matches?"] = domMatches;
-  if (typeof preventDefault_ === "function") PRIMITIVES["prevent-default"] = preventDefault_;
-  if (typeof eventModifierKey_p === "function") PRIMITIVES["event-modifier-key?"] = eventModifierKey_p;
-  if (typeof elementValue === "function") PRIMITIVES["element-value"] = elementValue;
-  if (typeof domOuterHtml === "function") PRIMITIVES["dom-outer-html"] = domOuterHtml;
-  if (typeof domInnerHtml === "function") PRIMITIVES["dom-inner-html"] = domInnerHtml;
-  if (typeof domTextContent === "function") PRIMITIVES["dom-text-content"] = domTextContent;
-  if (typeof domCreateElement === "function") PRIMITIVES["dom-create-element"] = domCreateElement;
-  if (typeof domAppend === "function") PRIMITIVES["dom-append"] = domAppend;
-  if (typeof domAppendToHead === "function") PRIMITIVES["dom-append-to-head"] = domAppendToHead;
-  if (typeof jsonParse === "function") PRIMITIVES["json-parse"] = jsonParse;
-  if (typeof nowMs === "function") PRIMITIVES["now-ms"] = nowMs;
-  PRIMITIVES["sx-parse"] = sxParse;
-  PRIMITIVES["console-log"] = function() { console.log.apply(console, ["[sx]"].concat(Array.prototype.slice.call(arguments))); return arguments.length > 0 ? arguments[0] : NIL; };''')
+  // -----------------------------------------------------------------------
+  // Core primitives that require native JS (cannot be expressed via FFI)
+  // -----------------------------------------------------------------------
+  PRIMITIVES["error"] = function(msg) { throw new Error(msg); };''']
     if has_deps:
         lines.append('''
-  // Expose deps module functions as primitives so runtime-evaluated SX code
-  // (e.g. test-deps.sx in browser) can call them
-  // Platform functions (from PLATFORM_DEPS_JS)
+  // Platform deps functions (native JS, not transpiled — need explicit registration)
   PRIMITIVES["component-deps"] = componentDeps;
   PRIMITIVES["component-set-deps!"] = componentSetDeps;
   PRIMITIVES["component-css-classes"] = componentCssClasses;
-  PRIMITIVES["env-components"] = envComponents;
   PRIMITIVES["regex-find-all"] = regexFindAll;
-  PRIMITIVES["scan-css-classes"] = scanCssClasses;
-  // Transpiled functions (from deps.sx)
-  PRIMITIVES["scan-refs"] = scanRefs;
-  PRIMITIVES["scan-refs-walk"] = scanRefsWalk;
-  PRIMITIVES["transitive-deps"] = transitiveDeps;
-  PRIMITIVES["transitive-deps-walk"] = transitiveDepsWalk;
-  PRIMITIVES["compute-all-deps"] = computeAllDeps;
-  PRIMITIVES["scan-components-from-source"] = scanComponentsFromSource;
-  PRIMITIVES["components-needed"] = componentsNeeded;
-  PRIMITIVES["page-component-bundle"] = pageComponentBundle;
-  PRIMITIVES["page-css-classes"] = pageCssClasses;
-  PRIMITIVES["scan-io-refs-walk"] = scanIoRefsWalk;
-  PRIMITIVES["scan-io-refs"] = scanIoRefs;
-  PRIMITIVES["transitive-io-refs-walk"] = transitiveIoRefsWalk;
-  PRIMITIVES["transitive-io-refs"] = transitiveIoRefs;
-  PRIMITIVES["compute-all-io-refs"] = computeAllIoRefs;
-  PRIMITIVES["component-io-refs-cached"] = componentIoRefsCached;
-  PRIMITIVES["component-pure?"] = componentPure_p;
-  PRIMITIVES["render-target"] = renderTarget;
-  PRIMITIVES["page-render-plan"] = pageRenderPlan;''')
-    if has_page_helpers:
-        lines.append('''
-  // Expose page-helper functions as primitives
-  PRIMITIVES["categorize-special-forms"] = categorizeSpecialForms;
-  PRIMITIVES["extract-define-kwargs"] = extractDefineKwargs;
-  PRIMITIVES["build-reference-data"] = buildReferenceData;
-  PRIMITIVES["build-ref-items-with-href"] = buildRefItemsWithHref;
-  PRIMITIVES["build-attr-detail"] = buildAttrDetail;
-  PRIMITIVES["build-header-detail"] = buildHeaderDetail;
-  PRIMITIVES["build-event-detail"] = buildEventDetail;
-  PRIMITIVES["build-component-source"] = buildComponentSource;
-  PRIMITIVES["build-bundle-analysis"] = buildBundleAnalysis;
-  PRIMITIVES["build-routing-analysis"] = buildRoutingAnalysis;
-  PRIMITIVES["build-affinity-analysis"] = buildAffinityAnalysis;''')
+  PRIMITIVES["scan-css-classes"] = scanCssClasses;''')
     return "\n".join(lines)
 
 
diff --git a/hosts/javascript/transpiler.sx b/hosts/javascript/transpiler.sx
index 0fc612e..d426810 100644
--- a/hosts/javascript/transpiler.sx
+++ b/hosts/javascript/transpiler.sx
@@ -624,6 +624,7 @@
   "scope-push!" "scopePush"
   "scope-pop!" "scopePop"
   "scope-emit!" "scopeEmit"
+  "scope-emitted" "sxEmitted"
   "scope-peek" "scopePeek"
   "provide-push!" "providePush"
   "provide-pop!" "providePop"
diff --git a/shared/static/scripts/sx-browser.js b/shared/static/scripts/sx-browser.js
index 1f6aeb0..c7b0c2b 100644
--- a/shared/static/scripts/sx-browser.js
+++ b/shared/static/scripts/sx-browser.js
@@ -14,7 +14,7 @@
   // =========================================================================
 
   var NIL = Object.freeze({ _nil: true, toString: function() { return "nil"; } });
-  var SX_VERSION = "2026-03-24T10:16:21Z";
+  var SX_VERSION = "2026-03-24T11:14:33Z";
 
   function isNil(x) { return x === NIL || x === null || x === undefined; }
   function isSxTruthy(x) { return x !== false && !isNil(x); }
@@ -555,17 +555,6 @@
     lst[idx] = val;
     return NIL;
   };
-  // Cookie access — isomorphic state persistence
-  PRIMITIVES["set-cookie"] = function(name, value, days) {
-    var d = days || 365;
-    var expires = new Date(Date.now() + d * 864e5).toUTCString();
-    document.cookie = name + "=" + encodeURIComponent(value) + ";expires=" + expires + ";path=/;SameSite=Lax";
-    return NIL;
-  };
-  PRIMITIVES["get-cookie"] = function(name) {
-    var m = document.cookie.match(new RegExp("(?:^|;\\s*)" + name + "=([^;]*)"));
-    return m ? decodeURIComponent(m[1]) : NIL;
-  };
 
   PRIMITIVES["env-parent"] = function(env) {
     if (env && Object.getPrototypeOf(env) !== Object.prototype &&
@@ -2648,7 +2637,7 @@ PRIMITIVES["render-html-component"] = renderHtmlComponent;
   var isVoid = contains(VOID_ELEMENTS, tag);
   return (isSxTruthy(isVoid) ? (String("<") + String(tag) + String(renderAttrs(attrs)) + String(" />")) : (scopePush("element-attrs", NIL), (function() {
   var content = join("", map(function(c) { return renderToHtml(c, env); }, children));
-  { var _c = scopeEmitted("element-attrs"); for (var _i = 0; _i < _c.length; _i++) { var spreadDict = _c[_i]; mergeSpreadAttrs(attrs, spreadDict); } }
+  { var _c = sxEmitted("element-attrs"); for (var _i = 0; _i < _c.length; _i++) { var spreadDict = _c[_i]; mergeSpreadAttrs(attrs, spreadDict); } }
   scopePop("element-attrs");
   return (String("<") + String(tag) + String(renderAttrs(attrs)) + String(">") + String(content) + String("</") + String(tag) + String(">"));
 })()));
@@ -2674,7 +2663,7 @@ PRIMITIVES["render-html-element"] = renderHtmlElement;
   scopePush("element-attrs", NIL);
   return (function() {
   var content = join("", map(function(c) { return renderToHtml(c, env); }, children));
-  { var _c = scopeEmitted("element-attrs"); for (var _i = 0; _i < _c.length; _i++) { var spreadDict = _c[_i]; mergeSpreadAttrs(lakeAttrs, spreadDict); } }
+  { var _c = sxEmitted("element-attrs"); for (var _i = 0; _i < _c.length; _i++) { var spreadDict = _c[_i]; mergeSpreadAttrs(lakeAttrs, spreadDict); } }
   scopePop("element-attrs");
   return (String("<") + String(lakeTag) + String(renderAttrs(lakeAttrs)) + String(">") + String(content) + String("</") + String(lakeTag) + String(">"));
 })();
@@ -2701,7 +2690,7 @@ PRIMITIVES["render-html-lake"] = renderHtmlLake;
   scopePush("element-attrs", NIL);
   return (function() {
   var content = join("", map(function(c) { return renderToHtml(c, env); }, children));
-  { var _c = scopeEmitted("element-attrs"); for (var _i = 0; _i < _c.length; _i++) { var spreadDict = _c[_i]; mergeSpreadAttrs(marshAttrs, spreadDict); } }
+  { var _c = sxEmitted("element-attrs"); for (var _i = 0; _i < _c.length; _i++) { var spreadDict = _c[_i]; mergeSpreadAttrs(marshAttrs, spreadDict); } }
   scopePop("element-attrs");
   return (String("<") + String(marshTag) + String(renderAttrs(marshAttrs)) + String(">") + String(content) + String("</") + String(marshTag) + String(">"));
 })();
@@ -5823,121 +5812,17 @@ PRIMITIVES["resource"] = resource;
     return _rawCallLambda(f, args, callerEnv);
   };
 
-  // Expose render functions as primitives so SX code can call them
-  if (typeof renderToHtml === "function") PRIMITIVES["render-to-html"] = renderToHtml;
-  if (typeof renderToSx === "function") PRIMITIVES["render-to-sx"] = renderToSx;
-  if (typeof aser === "function") PRIMITIVES["aser"] = aser;
-  if (typeof renderToDom === "function") PRIMITIVES["render-to-dom"] = renderToDom;
-
-  // Expose signal functions as primitives so runtime-evaluated SX code
-  // (e.g. island bodies from .sx files) can call them
-  PRIMITIVES["signal"] = signal;
-  PRIMITIVES["signal?"] = isSignal;
-  PRIMITIVES["deref"] = deref;
-  PRIMITIVES["reset!"] = reset_b;
-  PRIMITIVES["swap!"] = swap_b;
-  PRIMITIVES["computed"] = computed;
-  PRIMITIVES["effect"] = effect;
-  PRIMITIVES["batch"] = batch;
-  // Timer primitives for island code
-  PRIMITIVES["set-interval"] = setInterval_;
-  PRIMITIVES["clear-interval"] = clearInterval_;
-  // Reactive DOM helpers for island code
-  PRIMITIVES["reactive-text"] = reactiveText;
-  PRIMITIVES["create-text-node"] = createTextNode;
-  PRIMITIVES["dom-set-text-content"] = domSetTextContent;
-  PRIMITIVES["dom-listen"] = domListen;
-  PRIMITIVES["dom-dispatch"] = domDispatch;
-  PRIMITIVES["event-detail"] = eventDetail;
-  PRIMITIVES["resource"] = resource;
-  PRIMITIVES["promise-delayed"] = promiseDelayed;
-  PRIMITIVES["promise-then"] = promiseThen;
-  PRIMITIVES["def-store"] = defStore;
-  PRIMITIVES["use-store"] = useStore;
-  PRIMITIVES["emit-event"] = emitEvent;
-  PRIMITIVES["on-event"] = onEvent;
-  PRIMITIVES["bridge-event"] = bridgeEvent;
-  // DOM primitives for island code
-  PRIMITIVES["dom-focus"] = domFocus;
-  PRIMITIVES["dom-tag-name"] = domTagName;
-  PRIMITIVES["dom-get-prop"] = domGetProp;
-  PRIMITIVES["dom-set-prop"] = domSetProp;
-  PRIMITIVES["dom-call-method"] = domCallMethod;
-  PRIMITIVES["dom-post-message"] = domPostMessage;
-  PRIMITIVES["stop-propagation"] = stopPropagation_;
-  PRIMITIVES["error-message"] = errorMessage;
-  PRIMITIVES["schedule-idle"] = scheduleIdle;
+  // -----------------------------------------------------------------------
+  // Core primitives that require native JS (cannot be expressed via FFI)
+  // -----------------------------------------------------------------------
   PRIMITIVES["error"] = function(msg) { throw new Error(msg); };
-  PRIMITIVES["filter"] = filter;
-  // DOM primitives for sx-on:* handlers and data-init scripts
-  if (typeof domBody === "function") PRIMITIVES["dom-body"] = domBody;
-  if (typeof domQuery === "function") PRIMITIVES["dom-query"] = domQuery;
-  if (typeof domQueryAll === "function") PRIMITIVES["dom-query-all"] = domQueryAll;
-  if (typeof domQueryById === "function") PRIMITIVES["dom-query-by-id"] = domQueryById;
-  if (typeof domSetAttr === "function") PRIMITIVES["dom-set-attr"] = domSetAttr;
-  if (typeof domGetAttr === "function") PRIMITIVES["dom-get-attr"] = domGetAttr;
-  if (typeof domRemoveAttr === "function") PRIMITIVES["dom-remove-attr"] = domRemoveAttr;
-  if (typeof domHasAttr === "function") PRIMITIVES["dom-has-attr?"] = domHasAttr;
-  if (typeof domAddClass === "function") PRIMITIVES["dom-add-class"] = domAddClass;
-  if (typeof domRemoveClass === "function") PRIMITIVES["dom-remove-class"] = domRemoveClass;
-  if (typeof domHasClass === "function") PRIMITIVES["dom-has-class?"] = domHasClass;
-  if (typeof domClosest === "function") PRIMITIVES["dom-closest"] = domClosest;
-  if (typeof domMatches === "function") PRIMITIVES["dom-matches?"] = domMatches;
-  if (typeof preventDefault_ === "function") PRIMITIVES["prevent-default"] = preventDefault_;
-  if (typeof eventModifierKey_p === "function") PRIMITIVES["event-modifier-key?"] = eventModifierKey_p;
-  if (typeof elementValue === "function") PRIMITIVES["element-value"] = elementValue;
-  if (typeof domOuterHtml === "function") PRIMITIVES["dom-outer-html"] = domOuterHtml;
-  if (typeof domInnerHtml === "function") PRIMITIVES["dom-inner-html"] = domInnerHtml;
-  if (typeof domTextContent === "function") PRIMITIVES["dom-text-content"] = domTextContent;
-  if (typeof domCreateElement === "function") PRIMITIVES["dom-create-element"] = domCreateElement;
-  if (typeof domAppend === "function") PRIMITIVES["dom-append"] = domAppend;
-  if (typeof domAppendToHead === "function") PRIMITIVES["dom-append-to-head"] = domAppendToHead;
-  if (typeof jsonParse === "function") PRIMITIVES["json-parse"] = jsonParse;
-  if (typeof nowMs === "function") PRIMITIVES["now-ms"] = nowMs;
-  PRIMITIVES["sx-parse"] = sxParse;
-  PRIMITIVES["console-log"] = function() { console.log.apply(console, ["[sx]"].concat(Array.prototype.slice.call(arguments))); return arguments.length > 0 ? arguments[0] : NIL; };
 
-  // Expose deps module functions as primitives so runtime-evaluated SX code
-  // (e.g. test-deps.sx in browser) can call them
-  // Platform functions (from PLATFORM_DEPS_JS)
+  // Platform deps functions (native JS, not transpiled — need explicit registration)
   PRIMITIVES["component-deps"] = componentDeps;
   PRIMITIVES["component-set-deps!"] = componentSetDeps;
   PRIMITIVES["component-css-classes"] = componentCssClasses;
-  PRIMITIVES["env-components"] = envComponents;
   PRIMITIVES["regex-find-all"] = regexFindAll;
   PRIMITIVES["scan-css-classes"] = scanCssClasses;
-  // Transpiled functions (from deps.sx)
-  PRIMITIVES["scan-refs"] = scanRefs;
-  PRIMITIVES["scan-refs-walk"] = scanRefsWalk;
-  PRIMITIVES["transitive-deps"] = transitiveDeps;
-  PRIMITIVES["transitive-deps-walk"] = transitiveDepsWalk;
-  PRIMITIVES["compute-all-deps"] = computeAllDeps;
-  PRIMITIVES["scan-components-from-source"] = scanComponentsFromSource;
-  PRIMITIVES["components-needed"] = componentsNeeded;
-  PRIMITIVES["page-component-bundle"] = pageComponentBundle;
-  PRIMITIVES["page-css-classes"] = pageCssClasses;
-  PRIMITIVES["scan-io-refs-walk"] = scanIoRefsWalk;
-  PRIMITIVES["scan-io-refs"] = scanIoRefs;
-  PRIMITIVES["transitive-io-refs-walk"] = transitiveIoRefsWalk;
-  PRIMITIVES["transitive-io-refs"] = transitiveIoRefs;
-  PRIMITIVES["compute-all-io-refs"] = computeAllIoRefs;
-  PRIMITIVES["component-io-refs-cached"] = componentIoRefsCached;
-  PRIMITIVES["component-pure?"] = componentPure_p;
-  PRIMITIVES["render-target"] = renderTarget;
-  PRIMITIVES["page-render-plan"] = pageRenderPlan;
-
-  // Expose page-helper functions as primitives
-  PRIMITIVES["categorize-special-forms"] = categorizeSpecialForms;
-  PRIMITIVES["extract-define-kwargs"] = extractDefineKwargs;
-  PRIMITIVES["build-reference-data"] = buildReferenceData;
-  PRIMITIVES["build-ref-items-with-href"] = buildRefItemsWithHref;
-  PRIMITIVES["build-attr-detail"] = buildAttrDetail;
-  PRIMITIVES["build-header-detail"] = buildHeaderDetail;
-  PRIMITIVES["build-event-detail"] = buildEventDetail;
-  PRIMITIVES["build-component-source"] = buildComponentSource;
-  PRIMITIVES["build-bundle-analysis"] = buildBundleAnalysis;
-  PRIMITIVES["build-routing-analysis"] = buildRoutingAnalysis;
-  PRIMITIVES["build-affinity-analysis"] = buildAffinityAnalysis;
 
   // Override recursive cekRun with iterative loop (avoids stack overflow)
   cekRun = function(state) {
@@ -5974,20 +5859,6 @@ PRIMITIVES["resource"] = resource;
   function makeEnv() { return merge(componentEnv, PRIMITIVES); }
   PRIMITIVES["make-env"] = makeEnv;
 
-  // localStorage — defined here (before boot) so islands can use at hydration
-  PRIMITIVES["local-storage-get"] = function(key) {
-    try { var v = localStorage.getItem(key); return v === null ? NIL : v; }
-    catch (e) { return NIL; }
-  };
-  PRIMITIVES["local-storage-set"] = function(key, val) {
-    try { localStorage.setItem(key, val); } catch (e) {}
-    return NIL;
-  };
-  PRIMITIVES["local-storage-remove"] = function(key) {
-    try { localStorage.removeItem(key); } catch (e) {}
-    return NIL;
-  };
-
 
   // === stdlib.sx (eval'd at runtime, not transpiled) ===
   (function() {
diff --git a/web/lib/browser.sx b/web/lib/browser.sx
index f2ee4fb..94d17ab 100644
--- a/web/lib/browser.sx
+++ b/web/lib/browser.sx
@@ -169,3 +169,43 @@
 (define now-ms
   (fn ()
     (host-call (host-global "Date") "now")))
+
+
+;; --------------------------------------------------------------------------
+;; Scheduling
+;; --------------------------------------------------------------------------
+
+(define schedule-idle
+  (fn (f)
+    (let ((cb (host-callback f)))
+      (if (host-get (dom-window) "requestIdleCallback")
+        (host-call (dom-window) "requestIdleCallback" cb)
+        (set-timeout cb 0)))))
+
+
+;; --------------------------------------------------------------------------
+;; Cookies
+;; --------------------------------------------------------------------------
+
+(define set-cookie
+  (fn (name value days)
+    (let ((d (or days 365))
+          (expires (host-call
+                     (host-new "Date"
+                       (+ (host-call (host-global "Date") "now")
+                          (* d 864e5)))
+                     "toUTCString")))
+      (host-set! (dom-document) "cookie"
+        (str name "="
+             (host-call nil "encodeURIComponent" value)
+             ";expires=" expires ";path=/;SameSite=Lax")))))
+
+(define get-cookie
+  (fn (name)
+    (let ((cookies (host-get (dom-document) "cookie"))
+          (match (host-call cookies "match"
+                   (host-new "RegExp"
+                     (str "(?:^|;\\s*)" name "=([^;]*)")))))
+      (if match
+        (host-call nil "decodeURIComponent" (host-get match 1))
+        nil))))
diff --git a/web/lib/dom.sx b/web/lib/dom.sx
index 427a2f7..10a7e65 100644
--- a/web/lib/dom.sx
+++ b/web/lib/dom.sx
@@ -263,6 +263,29 @@
 (define event-detail
   (fn (evt) (host-get evt "detail")))
 
+(define prevent-default
+  (fn (e) (when e (host-call e "preventDefault"))))
+
+(define stop-propagation
+  (fn (e) (when e (host-call e "stopPropagation"))))
+
+(define event-modifier-key?
+  (fn (e)
+    (and e (or (host-get e "ctrlKey") (host-get e "metaKey")
+               (host-get e "shiftKey") (host-get e "altKey")))))
+
+(define element-value
+  (fn (el)
+    (if (and el (not (nil? (host-get el "value"))))
+      (host-get el "value")
+      nil)))
+
+(define error-message
+  (fn (e)
+    (if (and e (host-get e "message"))
+      (host-get e "message")
+      (str e))))
+
 
 ;; --------------------------------------------------------------------------
 ;; DOM data storage