diff --git a/shared/static/scripts/sx-browser.js b/shared/static/scripts/sx-browser.js
index f3d7cae..9d00e02 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 = "2026-03-10T20:59:39Z";
+  var SX_VERSION = "2026-03-11T03:49:41Z";
 
   function isNil(x) { return x === NIL || x === null || x === undefined; }
   function isSxTruthy(x) { return x !== false && !isNil(x); }
@@ -233,10 +233,17 @@
   // Render dispatch — call the active adapter's render function.
   // Set by each adapter when loaded; defaults to identity (no rendering).
   var _renderExprFn = null;
+
+  // Render mode flag — set by render-to-html/aser, checked by eval-list.
+  // When false, render expressions fall through to evalCall.
+  var _renderMode = false;
+  function renderActiveP() { return _renderMode; }
+  function setRenderActiveB(val) { _renderMode = !!val; }
+
   function renderExpr(expr, env) {
     if (_renderExprFn) return _renderExprFn(expr, env);
-    // No adapter loaded — just return the expression as-is
-    return expr;
+    // No adapter loaded — fall through to evalCall
+    return evalCall(first(expr), rest(expr), env);
   }
 
   function stripPrefix(s, prefix) {
@@ -614,7 +621,7 @@
   return (isSxTruthy((name == "if")) ? sfIf(args, env) : (isSxTruthy((name == "when")) ? sfWhen(args, env) : (isSxTruthy((name == "cond")) ? sfCond(args, env) : (isSxTruthy((name == "case")) ? sfCase(args, env) : (isSxTruthy((name == "and")) ? sfAnd(args, env) : (isSxTruthy((name == "or")) ? sfOr(args, env) : (isSxTruthy((name == "let")) ? sfLet(args, env) : (isSxTruthy((name == "let*")) ? sfLet(args, env) : (isSxTruthy((name == "letrec")) ? sfLetrec(args, env) : (isSxTruthy((name == "lambda")) ? sfLambda(args, env) : (isSxTruthy((name == "fn")) ? sfLambda(args, env) : (isSxTruthy((name == "define")) ? sfDefine(args, env) : (isSxTruthy((name == "defcomp")) ? sfDefcomp(args, env) : (isSxTruthy((name == "defisland")) ? sfDefisland(args, env) : (isSxTruthy((name == "defmacro")) ? sfDefmacro(args, env) : (isSxTruthy((name == "defstyle")) ? sfDefstyle(args, env) : (isSxTruthy((name == "defhandler")) ? sfDefhandler(args, env) : (isSxTruthy((name == "defpage")) ? sfDefpage(args, env) : (isSxTruthy((name == "defquery")) ? sfDefquery(args, env) : (isSxTruthy((name == "defaction")) ? sfDefaction(args, env) : (isSxTruthy((name == "begin")) ? sfBegin(args, env) : (isSxTruthy((name == "do")) ? sfBegin(args, env) : (isSxTruthy((name == "quote")) ? sfQuote(args, env) : (isSxTruthy((name == "quasiquote")) ? sfQuasiquote(args, env) : (isSxTruthy((name == "->")) ? sfThreadFirst(args, env) : (isSxTruthy((name == "set!")) ? sfSetBang(args, env) : (isSxTruthy((name == "reset")) ? sfReset(args, env) : (isSxTruthy((name == "shift")) ? sfShift(args, env) : (isSxTruthy((name == "dynamic-wind")) ? sfDynamicWind(args, env) : (isSxTruthy((name == "map")) ? hoMap(args, env) : (isSxTruthy((name == "map-indexed")) ? hoMapIndexed(args, env) : (isSxTruthy((name == "filter")) ? hoFilter(args, env) : (isSxTruthy((name == "reduce")) ? hoReduce(args, env) : (isSxTruthy((name == "some")) ? hoSome(args, env) : (isSxTruthy((name == "every?")) ? hoEvery(args, env) : (isSxTruthy((name == "for-each")) ? hoForEach(args, env) : (isSxTruthy((isSxTruthy(envHas(env, name)) && isMacro(envGet(env, name)))) ? (function() {
   var mac = envGet(env, name);
   return makeThunk(expandMacro(mac, args, env), env);
-})() : (isSxTruthy(isRenderExpr(expr)) ? renderExpr(expr, env) : evalCall(head, args, env)))))))))))))))))))))))))))))))))))))));
+})() : (isSxTruthy((isSxTruthy(renderActiveP()) && isRenderExpr(expr))) ? renderExpr(expr, env) : evalCall(head, args, env)))))))))))))))))))))))))))))))))))))));
 })() : evalCall(head, args, env)));
 })(); };
 
@@ -1228,7 +1235,8 @@ continue; } else { return NIL; } } };
   // === Transpiled from adapter-html ===
 
   // render-to-html
-  var renderToHtml = function(expr, env) { return (function() { var _m = typeOf(expr); if (_m == "nil") return ""; if (_m == "string") return escapeHtml(expr); if (_m == "number") return (String(expr)); if (_m == "boolean") return (isSxTruthy(expr) ? "true" : "false"); if (_m == "list") return (isSxTruthy(isEmpty(expr)) ? "" : renderListToHtml(expr, env)); if (_m == "symbol") return renderValueToHtml(trampoline(evalExpr(expr, env)), env); if (_m == "keyword") return escapeHtml(keywordName(expr)); if (_m == "raw-html") return rawHtmlContent(expr); return renderValueToHtml(trampoline(evalExpr(expr, env)), env); })(); };
+  var renderToHtml = function(expr, env) { setRenderActiveB(true);
+return (function() { var _m = typeOf(expr); if (_m == "nil") return ""; if (_m == "string") return escapeHtml(expr); if (_m == "number") return (String(expr)); if (_m == "boolean") return (isSxTruthy(expr) ? "true" : "false"); if (_m == "list") return (isSxTruthy(isEmpty(expr)) ? "" : renderListToHtml(expr, env)); if (_m == "symbol") return renderValueToHtml(trampoline(evalExpr(expr, env)), env); if (_m == "keyword") return escapeHtml(keywordName(expr)); if (_m == "raw-html") return rawHtmlContent(expr); return renderValueToHtml(trampoline(evalExpr(expr, env)), env); })(); };
 
   // render-value-to-html
   var renderValueToHtml = function(val, env) { return (function() { var _m = typeOf(val); if (_m == "nil") return ""; if (_m == "string") return escapeHtml(val); if (_m == "number") return (String(val)); if (_m == "boolean") return (isSxTruthy(val) ? "true" : "false"); if (_m == "list") return renderListToHtml(val, env); if (_m == "raw-html") return rawHtmlContent(val); return escapeHtml((String(val))); })(); };
@@ -1388,7 +1396,8 @@ continue; } else { return NIL; } } };
 })(); };
 
   // aser
-  var aser = function(expr, env) { return (function() { var _m = typeOf(expr); if (_m == "number") return expr; if (_m == "string") return expr; if (_m == "boolean") return expr; if (_m == "nil") return NIL; if (_m == "symbol") return (function() {
+  var aser = function(expr, env) { setRenderActiveB(true);
+return (function() { var _m = typeOf(expr); if (_m == "number") return expr; if (_m == "string") return expr; if (_m == "boolean") return expr; if (_m == "nil") return NIL; if (_m == "symbol") return (function() {
   var name = symbolName(expr);
   return (isSxTruthy(envHas(env, name)) ? envGet(env, name) : (isSxTruthy(isPrimitive(name)) ? getPrimitive(name) : (isSxTruthy((name == "true")) ? true : (isSxTruthy((name == "false")) ? false : (isSxTruthy((name == "nil")) ? NIL : error((String("Undefined symbol: ") + String(name))))))));
 })(); if (_m == "keyword") return keywordName(expr); if (_m == "list") return (isSxTruthy(isEmpty(expr)) ? [] : aserList(expr, env)); return expr; })(); };
diff --git a/shared/sx/ref/bootstrap_js.py b/shared/sx/ref/bootstrap_js.py
index 66b1942..0ba9161 100644
--- a/shared/sx/ref/bootstrap_js.py
+++ b/shared/sx/ref/bootstrap_js.py
@@ -189,6 +189,8 @@ class JSEmitter:
             "eval-call": "evalCall",
             "is-render-expr?": "isRenderExpr",
             "render-expr": "renderExpr",
+            "render-active?": "renderActiveP",
+            "set-render-active!": "setRenderActiveB",
             "call-lambda": "callLambda",
             "call-component": "callComponent",
             "parse-keyword-args": "parseKeywordArgs",
@@ -2497,10 +2499,17 @@ PLATFORM_JS_PRE = '''
   // Render dispatch — call the active adapter's render function.
   // Set by each adapter when loaded; defaults to identity (no rendering).
   var _renderExprFn = null;
+
+  // Render mode flag — set by render-to-html/aser, checked by eval-list.
+  // When false, render expressions fall through to evalCall.
+  var _renderMode = false;
+  function renderActiveP() { return _renderMode; }
+  function setRenderActiveB(val) { _renderMode = !!val; }
+
   function renderExpr(expr, env) {
     if (_renderExprFn) return _renderExprFn(expr, env);
-    // No adapter loaded — just return the expression as-is
-    return expr;
+    // No adapter loaded — fall through to evalCall
+    return evalCall(first(expr), rest(expr), env);
   }
 
   function stripPrefix(s, prefix) {
diff --git a/shared/sx/tests/test_parity.py b/shared/sx/tests/test_parity.py
index 5858d24..db809b0 100644
--- a/shared/sx/tests/test_parity.py
+++ b/shared/sx/tests/test_parity.py
@@ -268,7 +268,12 @@ class TestParityLambda:
         assert_parity("((fn (x) (+ x 1) (* x 2)) 5)")
 
     def test_rest_params(self):
-        assert_parity("((fn (&rest args) args) 1 2 3)")
+        # &rest is only supported in defcomp/defmacro, not bare lambda
+        # Both evaluators should error on this
+        with pytest.raises(Exception):
+            hw_eval("((fn (&rest args) args) 1 2 3)")
+        with pytest.raises(Exception):
+            ref_eval("((fn (&rest args) args) 1 2 3)")
 
 
 # ---------------------------------------------------------------------------