Merge branch 'main' into worktree-typed-sx

# Conflicts: # shared/sx/ref/platform_py.py # shared/sx/ref/sx_ref.py
2026-03-11 17:06:30 +00:00
parent e5dbe9f3da 0174fbfea3
commit b82fd7822d
47 changed files with 7522 additions and 1702 deletions
--- 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 = "2026-03-11T04:41:27Z";
+  var SX_VERSION = "2026-03-11T16:56:11Z";

  function isNil(x) { return x === NIL || x === null || x === undefined; }
  function isSxTruthy(x) { return x !== false && !isNil(x); }
@@ -204,7 +204,7 @@

  // JSON / dict helpers for island state serialization
  function jsonSerialize(obj) {
-    try { return JSON.stringify(obj); } catch(e) { return "{}"; }
+    return JSON.stringify(obj);
  }
  function isEmptyDict(d) {
    if (!d || typeof d !== "object") return true;
@@ -214,11 +214,34 @@

  function envHas(env, name) { return name in env; }
  function envGet(env, name) { return env[name]; }
-  function envSet(env, name, val) { env[name] = val; }
+  function envSet(env, name, val) {
+    // Walk prototype chain to find where the variable is defined (for set!)
+    var obj = env;
+    while (obj !== null && obj !== Object.prototype) {
+      if (obj.hasOwnProperty(name)) { obj[name] = val; return; }
+      obj = Object.getPrototypeOf(obj);
+    }
+    // Not found in any parent scope — set on the immediate env
+    env[name] = val;
+  }
  function envExtend(env) { return Object.create(env); }
  function envMerge(base, overlay) {
+    // Same env or overlay is descendant of base — just extend, no copy.
+    // This prevents set! inside lambdas from modifying shadow copies.
+    if (base === overlay) return Object.create(base);
+    var p = overlay;
+    for (var d = 0; p && p !== Object.prototype && d < 100; d++) {
+      if (p === base) return Object.create(base);
+      p = Object.getPrototypeOf(p);
+    }
+    // General case: extend base, copy ONLY overlay properties that don't
+    // exist in the base chain (avoids shadowing closure bindings).
    var child = Object.create(base);
-    if (overlay) for (var k in overlay) if (overlay.hasOwnProperty(k)) child[k] = overlay[k];
+    if (overlay) {
+      for (var k in overlay) {
+        if (overlay.hasOwnProperty(k) && !(k in base)) child[k] = overlay[k];
+      }
+    }
    return child;
  }

@@ -732,9 +755,9 @@
  var kwargs = first(parsed);
  var children = nth(parsed, 1);
  var local = envMerge(componentClosure(comp), env);
-  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; local[p] = sxOr(dictGet(kwargs, p), NIL); } }
+  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; envSet(local, p, sxOr(dictGet(kwargs, p), NIL)); } }
  if (isSxTruthy(componentHasChildren(comp))) {
-  local["children"] = children;
+  envSet(local, "children", children);
 }
  return makeThunk(componentBody(comp), local);
 })(); };
@@ -764,8 +787,11 @@
  return (isSxTruthy((isSxTruthy(condition) && !isSxTruthy(isNil(condition)))) ? (forEach(function(e) { return trampoline(evalExpr(e, env)); }, slice(args, 1, (len(args) - 1))), makeThunk(last(args), env)) : NIL);
 })(); };

+  // cond-scheme?
+  var condScheme_p = function(clauses) { return isEvery(function(c) { return (isSxTruthy((typeOf(c) == "list")) && (len(c) == 2)); }, clauses); };
+
  // sf-cond
-  var sfCond = function(args, env) { return (isSxTruthy((isSxTruthy((typeOf(first(args)) == "list")) && (len(first(args)) == 2))) ? sfCondScheme(args, env) : sfCondClojure(args, env)); };
+  var sfCond = function(args, env) { return (isSxTruthy(condScheme_p(args)) ? sfCondScheme(args, env) : sfCondClojure(args, env)); };

  // sf-cond-scheme
  var sfCondScheme = function(clauses, env) { return (isSxTruthy(isEmpty(clauses)) ? NIL : (function() {
@@ -841,7 +867,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  var loopBody = (isSxTruthy((len(body) == 1)) ? first(body) : cons(makeSymbol("begin"), body));
  var loopFn = makeLambda(params, loopBody, env);
  loopFn.name = loopName;
-  lambdaClosure(loopFn)[loopName] = loopFn;
+  envSet(lambdaClosure(loopFn), loopName, loopFn);
  return (function() {
  var initVals = map(function(e) { return trampoline(evalExpr(e, env)); }, inits);
  return callLambda(loopFn, initVals, env);
@@ -865,7 +891,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  if (isSxTruthy((isSxTruthy(isLambda(value)) && isNil(lambdaName(value))))) {
  value.name = symbolName(nameSym);
 }
-  env[symbolName(nameSym)] = value;
+  envSet(env, symbolName(nameSym), value);
  return value;
 })(); };

@@ -881,7 +907,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  var affinity = defcompKwarg(args, "affinity", "auto");
  return (function() {
  var comp = makeComponent(compName, params, hasChildren, body, env, affinity);
-  env[symbolName(nameSym)] = comp;
+  envSet(env, symbolName(nameSym), comp);
  return comp;
 })();
 })(); };
@@ -924,7 +950,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  var hasChildren = nth(parsed, 1);
  return (function() {
  var island = makeIsland(compName, params, hasChildren, body, env);
-  env[symbolName(nameSym)] = island;
+  envSet(env, symbolName(nameSym), island);
  return island;
 })();
 })(); };
@@ -939,7 +965,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  var restParam = nth(parsed, 1);
  return (function() {
  var mac = makeMacro(params, restParam, body, env, symbolName(nameSym));
-  env[symbolName(nameSym)] = mac;
+  envSet(env, symbolName(nameSym), mac);
  return mac;
 })();
 })(); };
@@ -956,7 +982,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  var sfDefstyle = function(args, env) { return (function() {
  var nameSym = first(args);
  var value = trampoline(evalExpr(nth(args, 1), env));
-  env[symbolName(nameSym)] = value;
+  envSet(env, symbolName(nameSym), value);
  return value;
 })(); };

@@ -974,8 +1000,8 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  var head = first(template);
  return (isSxTruthy((isSxTruthy((typeOf(head) == "symbol")) && (symbolName(head) == "unquote"))) ? trampoline(evalExpr(nth(template, 1), env)) : reduce(function(result, item) { return (isSxTruthy((isSxTruthy((typeOf(item) == "list")) && isSxTruthy((len(item) == 2)) && isSxTruthy((typeOf(first(item)) == "symbol")) && (symbolName(first(item)) == "splice-unquote"))) ? (function() {
  var spliced = trampoline(evalExpr(nth(item, 1), env));
-  return (isSxTruthy((typeOf(spliced) == "list")) ? concat(result, spliced) : (isSxTruthy(isNil(spliced)) ? result : append(result, spliced)));
-})() : append(result, qqExpand(item, env))); }, [], template));
+  return (isSxTruthy((typeOf(spliced) == "list")) ? concat(result, spliced) : (isSxTruthy(isNil(spliced)) ? result : concat(result, [spliced])));
+})() : concat(result, [qqExpand(item, env)])); }, [], template));
 })())); };

  // sf-thread-first
@@ -996,7 +1022,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  var sfSetBang = function(args, env) { return (function() {
  var name = symbolName(first(args));
  var value = trampoline(evalExpr(nth(args, 1), env));
-  env[name] = value;
+  envSet(env, name, value);
  return value;
 })(); };

@@ -1021,7 +1047,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
 })(); }, NIL, range(0, (len(bindings) / 2))));
  (function() {
  var values = map(function(e) { return trampoline(evalExpr(e, local)); }, valExprs);
-  { var _c = zip(names, values); for (var _i = 0; _i < _c.length; _i++) { var pair = _c[_i]; local[first(pair)] = nth(pair, 1); } }
+  { var _c = zip(names, values); for (var _i = 0; _i < _c.length; _i++) { var pair = _c[_i]; envSet(local, first(pair), nth(pair, 1)); } }
  return forEach(function(val) { return (isSxTruthy(isLambda(val)) ? forEach(function(n) { return envSet(lambdaClosure(val), n, envGet(local, n)); }, names) : NIL); }, values);
 })();
  { var _c = slice(body, 0, (len(body) - 1)); for (var _i = 0; _i < _c.length; _i++) { var e = _c[_i]; trampoline(evalExpr(e, local)); } }
@@ -1046,9 +1072,9 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
  // expand-macro
  var expandMacro = function(mac, rawArgs, env) { return (function() {
  var local = envMerge(macroClosure(mac), env);
-  { var _c = mapIndexed(function(i, p) { return [p, i]; }, macroParams(mac)); for (var _i = 0; _i < _c.length; _i++) { var pair = _c[_i]; local[first(pair)] = (isSxTruthy((nth(pair, 1) < len(rawArgs))) ? nth(rawArgs, nth(pair, 1)) : NIL); } }
+  { var _c = mapIndexed(function(i, p) { return [p, i]; }, macroParams(mac)); for (var _i = 0; _i < _c.length; _i++) { var pair = _c[_i]; envSet(local, first(pair), (isSxTruthy((nth(pair, 1) < len(rawArgs))) ? nth(rawArgs, nth(pair, 1)) : NIL)); } }
  if (isSxTruthy(macroRestParam(mac))) {
-  local[macroRestParam(mac)] = slice(rawArgs, len(macroParams(mac)));
+  envSet(local, macroRestParam(mac), slice(rawArgs, len(macroParams(mac))));
 }
  return trampoline(evalExpr(macroBody(mac), local));
 })(); };
@@ -1143,7 +1169,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai
 })(); }, keys(attrs))); };

  // eval-cond
-  var evalCond = function(clauses, env) { return (isSxTruthy((isSxTruthy(!isSxTruthy(isEmpty(clauses))) && isSxTruthy((typeOf(first(clauses)) == "list")) && (len(first(clauses)) == 2))) ? evalCondScheme(clauses, env) : evalCondClojure(clauses, env)); };
+  var evalCond = function(clauses, env) { return (isSxTruthy(condScheme_p(clauses)) ? evalCondScheme(clauses, env) : evalCondClojure(clauses, env)); };

  // eval-cond-scheme
  var evalCondScheme = function(clauses, env) { return (isSxTruthy(isEmpty(clauses)) ? NIL : (function() {
@@ -1162,7 +1188,7 @@ return append_b(inits, nth(binding, 1)); }, bindings) : reduce(function(acc, pai

  // process-bindings
  var processBindings = function(bindings, env) { return (function() {
-  var local = merge(env);
+  var local = envExtend(env);
  { var _c = bindings; for (var _i = 0; _i < _c.length; _i++) { var pair = _c[_i]; if (isSxTruthy((isSxTruthy((typeOf(pair) == "list")) && (len(pair) >= 2)))) {
  (function() {
  var name = (isSxTruthy((typeOf(first(pair)) == "symbol")) ? symbolName(first(pair)) : (String(first(pair))));
@@ -1392,9 +1418,9 @@ return (function() { var _m = typeOf(expr); if (_m == "nil") return ""; if (_m =
 })(); }, {["i"]: 0, ["skip"]: false}, args);
  return (function() {
  var local = envMerge(componentClosure(comp), env);
-  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; local[p] = (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL); } }
+  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; envSet(local, p, (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL)); } }
  if (isSxTruthy(componentHasChildren(comp))) {
-  local["children"] = makeRawHtml(join("", map(function(c) { return renderToHtml(c, env); }, children)));
+  envSet(local, "children", makeRawHtml(join("", map(function(c) { return renderToHtml(c, env); }, children))));
 }
  return renderToHtml(componentBody(comp), local);
 })();
@@ -1458,20 +1484,20 @@ return (function() { var _m = typeOf(expr); if (_m == "nil") return ""; if (_m =
  return (function() {
  var local = envMerge(componentClosure(island), env);
  var islandName = componentName(island);
-  { var _c = componentParams(island); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; local[p] = (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL); } }
+  { var _c = componentParams(island); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; envSet(local, p, (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL)); } }
  if (isSxTruthy(componentHasChildren(island))) {
-  local["children"] = makeRawHtml(join("", map(function(c) { return renderToHtml(c, env); }, children)));
+  envSet(local, "children", makeRawHtml(join("", map(function(c) { return renderToHtml(c, env); }, children))));
 }
  return (function() {
  var bodyHtml = renderToHtml(componentBody(island), local);
-  var stateJson = serializeIslandState(kwargs);
-  return (String("<span data-sx-island=\"") + String(escapeAttr(islandName)) + String("\"") + String((isSxTruthy(stateJson) ? (String(" data-sx-state=\"") + String(escapeAttr(stateJson)) + String("\"")) : "")) + String(">") + String(bodyHtml) + String("</span>"));
+  var stateSx = serializeIslandState(kwargs);
+  return (String("<span data-sx-island=\"") + String(escapeAttr(islandName)) + String("\"") + String((isSxTruthy(stateSx) ? (String(" data-sx-state=\"") + String(escapeAttr(stateSx)) + String("\"")) : "")) + String(">") + String(bodyHtml) + String("</span>"));
 })();
 })();
 })(); };

  // serialize-island-state
-  var serializeIslandState = function(kwargs) { return (isSxTruthy(isEmptyDict(kwargs)) ? NIL : jsonSerialize(kwargs)); };
+  var serializeIslandState = function(kwargs) { return (isSxTruthy(isEmptyDict(kwargs)) ? NIL : sxSerialize(kwargs)); };


  // === Transpiled from adapter-sx ===
@@ -1505,30 +1531,34 @@ return (function() { var _m = typeOf(expr); if (_m == "number") return expr; if

  // aser-fragment
  var aserFragment = function(children, env) { return (function() {
-  var parts = filter(function(x) { return !isSxTruthy(isNil(x)); }, map(function(c) { return aser(c, env); }, children));
-  return (isSxTruthy(isEmpty(parts)) ? "" : (String("(<> ") + String(join(" ", map(serialize, parts))) + String(")")));
+  var parts = [];
+  { var _c = children; for (var _i = 0; _i < _c.length; _i++) { var c = _c[_i]; (function() {
+  var result = aser(c, env);
+  return (isSxTruthy((typeOf(result) == "list")) ? forEach(function(item) { return (isSxTruthy(!isSxTruthy(isNil(item))) ? append_b(parts, serialize(item)) : NIL); }, result) : (isSxTruthy(!isSxTruthy(isNil(result))) ? append_b(parts, serialize(result)) : NIL));
+})(); } }
+  return (isSxTruthy(isEmpty(parts)) ? "" : (String("(<> ") + String(join(" ", parts)) + String(")")));
 })(); };

  // aser-call
  var aserCall = function(name, args, env) { return (function() {
  var parts = [name];
-  reduce(function(state, arg) { return (function() {
-  var skip = get(state, "skip");
-  return (isSxTruthy(skip) ? assoc(state, "skip", false, "i", (get(state, "i") + 1)) : (isSxTruthy((isSxTruthy((typeOf(arg) == "keyword")) && ((get(state, "i") + 1) < len(args)))) ? (function() {
-  var val = aser(nth(args, (get(state, "i") + 1)), env);
+  var skip = false;
+  var i = 0;
+  { var _c = args; for (var _i = 0; _i < _c.length; _i++) { var arg = _c[_i]; (isSxTruthy(skip) ? ((skip = false), (i = (i + 1))) : (isSxTruthy((isSxTruthy((typeOf(arg) == "keyword")) && ((i + 1) < len(args)))) ? (function() {
+  var val = aser(nth(args, (i + 1)), env);
  if (isSxTruthy(!isSxTruthy(isNil(val)))) {
  parts.push((String(":") + String(keywordName(arg))));
  parts.push(serialize(val));
 }
-  return assoc(state, "skip", true, "i", (get(state, "i") + 1));
+  skip = true;
+  return (i = (i + 1));
 })() : (function() {
  var val = aser(arg, env);
  if (isSxTruthy(!isSxTruthy(isNil(val)))) {
-  parts.push(serialize(val));
+  (isSxTruthy((typeOf(val) == "list")) ? forEach(function(item) { return (isSxTruthy(!isSxTruthy(isNil(item))) ? append_b(parts, serialize(item)) : NIL); }, val) : append_b(parts, serialize(val)));
 }
-  return assoc(state, "i", (get(state, "i") + 1));
-})()));
-})(); }, {["i"]: 0, ["skip"]: false}, args);
+  return (i = (i + 1));
+})())); } }
  return (String("(") + String(join(" ", parts)) + String(")"));
 })(); };

@@ -1582,7 +1612,7 @@ return result; }, args);
  var coll = trampoline(evalExpr(nth(args, 1), env));
  return map(function(item) { return (isSxTruthy(isLambda(f)) ? (function() {
  var local = envMerge(lambdaClosure(f), env);
-  local[first(lambdaParams(f))] = item;
+  envSet(local, first(lambdaParams(f)), item);
  return aser(lambdaBody(f), local);
 })() : invoke(f, item)); }, coll);
 })() : (isSxTruthy((name == "map-indexed")) ? (function() {
@@ -1590,8 +1620,8 @@ return result; }, args);
  var coll = trampoline(evalExpr(nth(args, 1), env));
  return mapIndexed(function(i, item) { return (isSxTruthy(isLambda(f)) ? (function() {
  var local = envMerge(lambdaClosure(f), env);
-  local[first(lambdaParams(f))] = i;
-  local[nth(lambdaParams(f), 1)] = item;
+  envSet(local, first(lambdaParams(f)), i);
+  envSet(local, nth(lambdaParams(f), 1), item);
  return aser(lambdaBody(f), local);
 })() : invoke(f, i, item)); }, coll);
 })() : (isSxTruthy((name == "for-each")) ? (function() {
@@ -1600,7 +1630,7 @@ return result; }, args);
  var results = [];
  { var _c = coll; for (var _i = 0; _i < _c.length; _i++) { var item = _c[_i]; (isSxTruthy(isLambda(f)) ? (function() {
  var local = envMerge(lambdaClosure(f), env);
-  local[first(lambdaParams(f))] = item;
+  envSet(local, first(lambdaParams(f)), item);
  return append_b(results, aser(lambdaBody(f), local));
 })() : invoke(f, item)); } }
  return (isSxTruthy(isEmpty(results)) ? NIL : results);
@@ -1692,7 +1722,7 @@ return (function() { var _m = typeOf(expr); if (_m == "nil") return createFragme
 })(); }, {["i"]: 0, ["skip"]: false}, args);
  return (function() {
  var local = envMerge(componentClosure(comp), env);
-  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; local[p] = (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL); } }
+  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; envSet(local, p, (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL)); } }
  if (isSxTruthy(componentHasChildren(comp))) {
  (function() {
  var childFrag = createFragment();
@@ -1883,7 +1913,7 @@ return (function() { var _m = typeOf(expr); if (_m == "nil") return createFragme
  return (function() {
  var local = envMerge(componentClosure(island), env);
  var islandName = componentName(island);
-  { var _c = componentParams(island); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; local[p] = (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL); } }
+  { var _c = componentParams(island); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; envSet(local, p, (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL)); } }
  if (isSxTruthy(componentHasChildren(island))) {
  (function() {
  var childFrag = createFragment();
@@ -2998,9 +3028,9 @@ return postSwap(target); }))) : NIL);
  var exprs = sxParse(body);
  return domListen(el, eventName, function(e) { return (function() {
  var handlerEnv = envExtend({});
-  handlerEnv["event"] = e;
-  handlerEnv["this"] = el;
-  handlerEnv["detail"] = eventDetail(e);
+  envSet(handlerEnv, "event", e);
+  envSet(handlerEnv, "this", el);
+  envSet(handlerEnv, "detail", eventDetail(e));
  return forEach(function(expr) { return evalExpr(expr, handlerEnv); }, exprs);
 })(); });
 })()) : NIL);
@@ -3229,17 +3259,17 @@ callExpr.push(dictGet(kwargs, k)); } }
  // hydrate-island
  var hydrateIsland = function(el) { return (function() {
  var name = domGetAttr(el, "data-sx-island");
-  var stateJson = sxOr(domGetAttr(el, "data-sx-state"), "{}");
+  var stateSx = sxOr(domGetAttr(el, "data-sx-state"), "{}");
  return (function() {
  var compName = (String("~") + String(name));
  var env = getRenderEnv(NIL);
  return (function() {
  var comp = envGet(env, compName);
  return (isSxTruthy(!isSxTruthy(sxOr(isComponent(comp), isIsland(comp)))) ? logWarn((String("hydrate-island: unknown island ") + String(compName))) : (function() {
-  var kwargs = jsonParse(stateJson);
+  var kwargs = sxOr(first(sxParse(stateSx)), {});
  var disposers = [];
  var local = envMerge(componentClosure(comp), env);
-  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; local[p] = (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL); } }
+  { var _c = componentParams(comp); for (var _i = 0; _i < _c.length; _i++) { var p = _c[_i]; envSet(local, p, (isSxTruthy(dictHas(kwargs, p)) ? dictGet(kwargs, p) : NIL)); } }
  return (function() {
  var bodyDom = withIslandScope(function(disposable) { return append_b(disposers, disposable); }, function() { return renderToDom(componentBody(comp), local, NIL); });
  domSetTextContent(el, "");
@@ -3433,6 +3463,125 @@ callExpr.push(dictGet(kwargs, k)); } }
 })(); }, keys(env)); };


+  // === Transpiled from page-helpers (pure data transformation helpers) ===
+
+  // special-form-category-map
+  var specialFormCategoryMap = {"if": "Control Flow", "when": "Control Flow", "cond": "Control Flow", "case": "Control Flow", "and": "Control Flow", "or": "Control Flow", "let": "Binding", "let*": "Binding", "letrec": "Binding", "define": "Binding", "set!": "Binding", "lambda": "Functions & Components", "fn": "Functions & Components", "defcomp": "Functions & Components", "defmacro": "Functions & Components", "begin": "Sequencing & Threading", "do": "Sequencing & Threading", "->": "Sequencing & Threading", "quote": "Quoting", "quasiquote": "Quoting", "reset": "Continuations", "shift": "Continuations", "dynamic-wind": "Guards", "map": "Higher-Order Forms", "map-indexed": "Higher-Order Forms", "filter": "Higher-Order Forms", "reduce": "Higher-Order Forms", "some": "Higher-Order Forms", "every?": "Higher-Order Forms", "for-each": "Higher-Order Forms", "defstyle": "Domain Definitions", "defhandler": "Domain Definitions", "defpage": "Domain Definitions", "defquery": "Domain Definitions", "defaction": "Domain Definitions"};
+
+  // extract-define-kwargs
+  var extractDefineKwargs = function(expr) { return (function() {
+  var result = {};
+  var items = slice(expr, 2);
+  var n = len(items);
+  { var _c = range(0, n); for (var _i = 0; _i < _c.length; _i++) { var idx = _c[_i]; if (isSxTruthy((isSxTruthy(((idx + 1) < n)) && (typeOf(nth(items, idx)) == "keyword")))) {
+  (function() {
+  var key = keywordName(nth(items, idx));
+  var val = nth(items, (idx + 1));
+  return dictSet(result, key, (isSxTruthy((typeOf(val) == "list")) ? (String("(") + String(join(" ", map(serialize, val))) + String(")")) : (String(val))));
+})();
+} } }
+  return result;
+})(); };
+
+  // categorize-special-forms
+  var categorizeSpecialForms = function(parsedExprs) { return (function() {
+  var categories = {};
+  { var _c = parsedExprs; for (var _i = 0; _i < _c.length; _i++) { var expr = _c[_i]; if (isSxTruthy((isSxTruthy((typeOf(expr) == "list")) && isSxTruthy((len(expr) >= 2)) && isSxTruthy((typeOf(first(expr)) == "symbol")) && (symbolName(first(expr)) == "define-special-form")))) {
+  (function() {
+  var name = nth(expr, 1);
+  var kwargs = extractDefineKwargs(expr);
+  var category = sxOr(get(specialFormCategoryMap, name), "Other");
+  if (isSxTruthy(!isSxTruthy(dictHas(categories, category)))) {
+  categories[category] = [];
+}
+  return append_b(get(categories, category), {"name": name, "syntax": sxOr(get(kwargs, "syntax"), ""), "doc": sxOr(get(kwargs, "doc"), ""), "tail-position": sxOr(get(kwargs, "tail-position"), ""), "example": sxOr(get(kwargs, "example"), "")});
+})();
+} } }
+  return categories;
+})(); };
+
+  // build-ref-items-with-href
+  var buildRefItemsWithHref = function(items, basePath, detailKeys, nFields) { return map(function(item) { return (isSxTruthy((nFields == 3)) ? (function() {
+  var name = nth(item, 0);
+  var field2 = nth(item, 1);
+  var field3 = nth(item, 2);
+  return {"name": name, "desc": field2, "exists": field3, "href": (isSxTruthy((isSxTruthy(field3) && some(function(k) { return (k == name); }, detailKeys))) ? (String(basePath) + String(name)) : NIL)};
+})() : (function() {
+  var name = nth(item, 0);
+  var desc = nth(item, 1);
+  return {"name": name, "desc": desc, "href": (isSxTruthy(some(function(k) { return (k == name); }, detailKeys)) ? (String(basePath) + String(name)) : NIL)};
+})()); }, items); };
+
+  // build-reference-data
+  var buildReferenceData = function(slug, rawData, detailKeys) { return (function() { var _m = slug; if (_m == "attributes") return {"req-attrs": buildRefItemsWithHref(get(rawData, "req-attrs"), "/hypermedia/reference/attributes/", detailKeys, 3), "beh-attrs": buildRefItemsWithHref(get(rawData, "beh-attrs"), "/hypermedia/reference/attributes/", detailKeys, 3), "uniq-attrs": buildRefItemsWithHref(get(rawData, "uniq-attrs"), "/hypermedia/reference/attributes/", detailKeys, 3)}; if (_m == "headers") return {"req-headers": buildRefItemsWithHref(get(rawData, "req-headers"), "/hypermedia/reference/headers/", detailKeys, 3), "resp-headers": buildRefItemsWithHref(get(rawData, "resp-headers"), "/hypermedia/reference/headers/", detailKeys, 3)}; if (_m == "events") return {"events-list": buildRefItemsWithHref(get(rawData, "events-list"), "/hypermedia/reference/events/", detailKeys, 2)}; if (_m == "js-api") return {"js-api-list": map(function(item) { return {"name": nth(item, 0), "desc": nth(item, 1)}; }, get(rawData, "js-api-list"))}; return {"req-attrs": buildRefItemsWithHref(get(rawData, "req-attrs"), "/hypermedia/reference/attributes/", detailKeys, 3), "beh-attrs": buildRefItemsWithHref(get(rawData, "beh-attrs"), "/hypermedia/reference/attributes/", detailKeys, 3), "uniq-attrs": buildRefItemsWithHref(get(rawData, "uniq-attrs"), "/hypermedia/reference/attributes/", detailKeys, 3)}; })(); };
+
+  // build-attr-detail
+  var buildAttrDetail = function(slug, detail) { return (isSxTruthy(isNil(detail)) ? {"attr-not-found": true} : {"attr-not-found": NIL, "attr-title": slug, "attr-description": get(detail, "description"), "attr-example": get(detail, "example"), "attr-handler": get(detail, "handler"), "attr-demo": get(detail, "demo"), "attr-wire-id": (isSxTruthy(dictHas(detail, "handler")) ? (String("ref-wire-") + String(replace_(replace_(slug, ":", "-"), "*", "star"))) : NIL)}); };
+
+  // build-header-detail
+  var buildHeaderDetail = function(slug, detail) { return (isSxTruthy(isNil(detail)) ? {"header-not-found": true} : {"header-not-found": NIL, "header-title": slug, "header-direction": get(detail, "direction"), "header-description": get(detail, "description"), "header-example": get(detail, "example"), "header-demo": get(detail, "demo")}); };
+
+  // build-event-detail
+  var buildEventDetail = function(slug, detail) { return (isSxTruthy(isNil(detail)) ? {"event-not-found": true} : {"event-not-found": NIL, "event-title": slug, "event-description": get(detail, "description"), "event-example": get(detail, "example"), "event-demo": get(detail, "demo")}); };
+
+  // build-component-source
+  var buildComponentSource = function(compData) { return (function() {
+  var compType = get(compData, "type");
+  var name = get(compData, "name");
+  var params = get(compData, "params");
+  var hasChildren = get(compData, "has-children");
+  var bodySx = get(compData, "body-sx");
+  var affinity = get(compData, "affinity");
+  return (isSxTruthy((compType == "not-found")) ? (String(";; component ") + String(name) + String(" not found")) : (function() {
+  var paramStrs = (isSxTruthy(isEmpty(params)) ? (isSxTruthy(hasChildren) ? ["&rest", "children"] : []) : (isSxTruthy(hasChildren) ? append(cons("&key", params), ["&rest", "children"]) : cons("&key", params)));
+  var paramsSx = (String("(") + String(join(" ", paramStrs)) + String(")"));
+  var formName = (isSxTruthy((compType == "island")) ? "defisland" : "defcomp");
+  var affinityStr = (isSxTruthy((isSxTruthy((compType == "component")) && isSxTruthy(!isSxTruthy(isNil(affinity))) && !isSxTruthy((affinity == "auto")))) ? (String(" :affinity ") + String(affinity)) : "");
+  return (String("(") + String(formName) + String(" ") + String(name) + String(" ") + String(paramsSx) + String(affinityStr) + String("\n  ") + String(bodySx) + String(")"));
+})());
+})(); };
+
+  // build-bundle-analysis
+  var buildBundleAnalysis = function(pagesRaw, componentsRaw, totalComponents, totalMacros, pureCount, ioCount) { return (function() {
+  var pagesData = [];
+  { var _c = pagesRaw; for (var _i = 0; _i < _c.length; _i++) { var page = _c[_i]; (function() {
+  var neededNames = get(page, "needed-names");
+  var n = len(neededNames);
+  var pct = (isSxTruthy((totalComponents > 0)) ? round(((n / totalComponents) * 100)) : 0);
+  var savings = (100 - pct);
+  var pureInPage = 0;
+  var ioInPage = 0;
+  var pageIoRefs = [];
+  var compDetails = [];
+  { var _c = neededNames; for (var _i = 0; _i < _c.length; _i++) { var compName = _c[_i]; (function() {
+  var info = get(componentsRaw, compName);
+  return (isSxTruthy(!isSxTruthy(isNil(info))) ? ((isSxTruthy(get(info, "is-pure")) ? (pureInPage = (pureInPage + 1)) : ((ioInPage = (ioInPage + 1)), forEach(function(ref) { return (isSxTruthy(!isSxTruthy(some(function(r) { return (r == ref); }, pageIoRefs))) ? append_b(pageIoRefs, ref) : NIL); }, sxOr(get(info, "io-refs"), [])))), append_b(compDetails, {"name": compName, "is-pure": get(info, "is-pure"), "affinity": get(info, "affinity"), "render-target": get(info, "render-target"), "io-refs": sxOr(get(info, "io-refs"), []), "deps": sxOr(get(info, "deps"), []), "source": get(info, "source")})) : NIL);
+})(); } }
+  return append_b(pagesData, {"name": get(page, "name"), "path": get(page, "path"), "direct": get(page, "direct"), "needed": n, "pct": pct, "savings": savings, "io-refs": len(pageIoRefs), "pure-in-page": pureInPage, "io-in-page": ioInPage, "components": compDetails});
+})(); } }
+  return {"pages": pagesData, "total-components": totalComponents, "total-macros": totalMacros, "pure-count": pureCount, "io-count": ioCount};
+})(); };
+
+  // build-routing-analysis
+  var buildRoutingAnalysis = function(pagesRaw) { return (function() {
+  var pagesData = [];
+  var clientCount = 0;
+  var serverCount = 0;
+  { var _c = pagesRaw; for (var _i = 0; _i < _c.length; _i++) { var page = _c[_i]; (function() {
+  var hasData = get(page, "has-data");
+  var contentSrc = sxOr(get(page, "content-src"), "");
+  var mode = NIL;
+  var reason = "";
+  (isSxTruthy(hasData) ? ((mode = "server"), (reason = "Has :data expression — needs server IO"), (serverCount = (serverCount + 1))) : (isSxTruthy(isEmpty(contentSrc)) ? ((mode = "server"), (reason = "No content expression"), (serverCount = (serverCount + 1))) : ((mode = "client"), (clientCount = (clientCount + 1)))));
+  return append_b(pagesData, {"name": get(page, "name"), "path": get(page, "path"), "mode": mode, "has-data": hasData, "content-expr": (isSxTruthy((len(contentSrc) > 80)) ? (String(slice(contentSrc, 0, 80)) + String("...")) : contentSrc), "reason": reason});
+})(); } }
+  return {"pages": pagesData, "total-pages": (clientCount + serverCount), "client-count": clientCount, "server-count": serverCount};
+})(); };
+
+  // build-affinity-analysis
+  var buildAffinityAnalysis = function(demoComponents, pagePlans) { return {"components": demoComponents, "page-plans": pagePlans}; };
+
+
  // === Transpiled from router (client-side route matching) ===

  // split-path-segments
@@ -3853,8 +4002,11 @@ return (isSxTruthy((_batchDepth == 0)) ? (function() {
  function domListen(el, name, handler) {
    if (!_hasDom || !el) return function() {};
    // Wrap SX lambdas from runtime-evaluated island code into native fns
+    // If lambda takes 0 params, call without event arg (convenience for on-click handlers)
    var wrapped = isLambda(handler)
-      ? function(e) { try { invoke(handler, e); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } }
+      ? (lambdaParams(handler).length === 0
+        ? function(e) { try { invoke(handler); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } }
+        : function(e) { try { invoke(handler, e); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } })
      : handler;
    if (name === "click") logInfo("domListen: click on <" + (el.tagName||"?").toLowerCase() + "> text=" + (el.textContent||"").substring(0,20) + " isLambda=" + isLambda(handler));
    el.addEventListener(name, wrapped);
@@ -3947,7 +4099,7 @@ return (isSxTruthy((_batchDepth == 0)) ? (function() {
    }
  }

-  function nowMs() { return Date.now(); }
+  function nowMs() { return (typeof performance !== "undefined") ? performance.now() : Date.now(); }

  function parseHeaderValue(s) {
    if (!s) return null;
@@ -5060,6 +5212,10 @@ return (isSxTruthy((_batchDepth == 0)) ? (function() {
  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 jsonParse === "function") PRIMITIVES["json-parse"] = jsonParse;
+  if (typeof nowMs === "function") PRIMITIVES["now-ms"] = nowMs;
+  PRIMITIVES["sx-parse"] = sxParse;

  // Expose deps module functions as primitives so runtime-evaluated SX code
  // (e.g. test-deps.sx in browser) can call them
@@ -5090,6 +5246,19 @@ return (isSxTruthy((_batchDepth == 0)) ? (function() {
  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;
+
  // =========================================================================
  // Async IO: Promise-aware rendering for client-side IO primitives
  // =========================================================================
@@ -5823,6 +5992,15 @@ return (isSxTruthy((_batchDepth == 0)) ? (function() {
    transitiveIoRefs: transitiveIoRefs,
    computeAllIoRefs: computeAllIoRefs,
    componentPure_p: componentPure_p,
+    categorizeSpecialForms: categorizeSpecialForms,
+    buildReferenceData: buildReferenceData,
+    buildAttrDetail: buildAttrDetail,
+    buildHeaderDetail: buildHeaderDetail,
+    buildEventDetail: buildEventDetail,
+    buildComponentSource: buildComponentSource,
+    buildBundleAnalysis: buildBundleAnalysis,
+    buildRoutingAnalysis: buildRoutingAnalysis,
+    buildAffinityAnalysis: buildAffinityAnalysis,
    splitPathSegments: splitPathSegments,
    parseRoutePattern: parseRoutePattern,
    matchRoute: matchRoute,
--- a/shared/sx/init.py
+++ b/shared/sx/init.py
@@ -31,11 +31,8 @@ from .parser import (
    parse_all,
    serialize,
 )
-from .evaluator import (
-    EvalError,
-    evaluate,
-    make_env,
-)
+from .types import EvalError
+from .ref.sx_ref import evaluate, make_env

 from .primitives import (
    all_primitives,
--- a/shared/sx/async_eval.py
+++ b/shared/sx/async_eval.py
@@ -53,7 +53,8 @@ from .types import Component, Island, Keyword, Lambda, Macro, NIL, Symbol
 _expand_components: contextvars.ContextVar[bool] = contextvars.ContextVar(
    "_expand_components", default=False
 )
-from .evaluator import _expand_macro, EvalError
+from .ref.sx_ref import expand_macro as _expand_macro
+from .types import EvalError
 from .primitives import _PRIMITIVES
 from .primitives_io import IO_PRIMITIVES, RequestContext, execute_io
 from .parser import SxExpr, serialize
@@ -420,23 +421,23 @@ async def _asf_define(expr, env, ctx):


 async def _asf_defcomp(expr, env, ctx):
-    from .evaluator import _sf_defcomp
-    return _sf_defcomp(expr, env)
+    from .ref.sx_ref import sf_defcomp
+    return sf_defcomp(expr[1:], env)


 async def _asf_defstyle(expr, env, ctx):
-    from .evaluator import _sf_defstyle
-    return _sf_defstyle(expr, env)
+    from .ref.sx_ref import sf_defstyle
+    return sf_defstyle(expr[1:], env)


 async def _asf_defmacro(expr, env, ctx):
-    from .evaluator import _sf_defmacro
-    return _sf_defmacro(expr, env)
+    from .ref.sx_ref import sf_defmacro
+    return sf_defmacro(expr[1:], env)


 async def _asf_defhandler(expr, env, ctx):
-    from .evaluator import _sf_defhandler
-    return _sf_defhandler(expr, env)
+    from .ref.sx_ref import sf_defhandler
+    return sf_defhandler(expr[1:], env)


 async def _asf_begin(expr, env, ctx):
@@ -599,7 +600,7 @@ async def _asf_reset(expr, env, ctx):
            _ASYNC_RESET_RESUME.append(value if value is not None else NIL)
            try:
                # Sync re-evaluation; the async caller will trampoline
-                from .evaluator import _eval as sync_eval, _trampoline
+                from .ref.sx_ref import eval_expr as sync_eval, trampoline as _trampoline
                return _trampoline(sync_eval(body, env))
            finally:
                _ASYNC_RESET_RESUME.pop()
--- a/shared/sx/evaluator.py
+++ b/shared/sx/evaluator.py
@@ -1,94 +0,0 @@
-"""
-S-expression evaluator — thin shim over bootstrapped sx_ref.py.
-
-All evaluation logic lives in the spec (shared/sx/ref/eval.sx) and is
-bootstrapped to Python (shared/sx/ref/sx_ref.py).  This module re-exports
-the public API and internal helpers under their historical names so that
-existing callers don't need updating.
-
-Imports are lazy (inside functions/properties) to avoid circular imports
-during bootstrapping: bootstrap_py.py → parser → __init__ → evaluator → sx_ref.
-"""
-
-from __future__ import annotations
-
-
-def _ref():
-    """Lazy import of the bootstrapped evaluator."""
-    from .ref import sx_ref
-    return sx_ref
-
-
-# ---------------------------------------------------------------------------
-# Public API — these are the most used, so we make them importable directly
-# ---------------------------------------------------------------------------
-
-class EvalError(Exception):
-    """Error during expression evaluation.
-
-    Delegates to the bootstrapped EvalError at runtime but is defined here
-    so imports don't fail during bootstrapping.
-    """
-    pass
-
-
-def evaluate(expr, env=None):
-    return _ref().evaluate(expr, env)
-
-
-def make_env(**kwargs):
-    return _ref().make_env(**kwargs)
-
-
-# ---------------------------------------------------------------------------
-# Internal helpers — used by html.py, async_eval.py, handlers.py, etc.
-# ---------------------------------------------------------------------------
-
-def _eval(expr, env):
-    return _ref().eval_expr(expr, env)
-
-
-def _trampoline(val):
-    return _ref().trampoline(val)
-
-
-def _call_lambda(fn, args, caller_env):
-    return _ref().call_lambda(fn, args, caller_env)
-
-
-def _call_component(comp, raw_args, env):
-    return _ref().call_component(comp, raw_args, env)
-
-
-def _expand_macro(macro, raw_args, env):
-    return _ref().expand_macro(macro, raw_args, env)
-
-
-# ---------------------------------------------------------------------------
-# Special-form wrappers: callers pass (expr, env) with expr[0] = head symbol.
-# sx_ref.py special forms take (args, env) where args = expr[1:].
-# ---------------------------------------------------------------------------
-
-def _sf_defcomp(expr, env):
-    return _ref().sf_defcomp(expr[1:], env)
-
-def _sf_defisland(expr, env):
-    return _ref().sf_defisland(expr[1:], env)
-
-def _sf_defstyle(expr, env):
-    return _ref().sf_defstyle(expr[1:], env)
-
-def _sf_defmacro(expr, env):
-    return _ref().sf_defmacro(expr[1:], env)
-
-def _sf_defhandler(expr, env):
-    return _ref().sf_defhandler(expr[1:], env)
-
-def _sf_defpage(expr, env):
-    return _ref().sf_defpage(expr[1:], env)
-
-def _sf_defquery(expr, env):
-    return _ref().sf_defquery(expr[1:], env)
-
-def _sf_defaction(expr, env):
-    return _ref().sf_defaction(expr[1:], env)
--- a/shared/sx/handlers.py
+++ b/shared/sx/handlers.py
@@ -70,10 +70,7 @@ def load_handler_file(filepath: str, service_name: str) -> list[HandlerDef]:
    """Parse an .sx file, evaluate it, and register any HandlerDef values."""
    from .parser import parse_all
    import os
-    if os.environ.get("SX_USE_REF") == "1":
-        from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
-    else:
-        from .evaluator import _eval as _raw_eval, _trampoline
+    from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
    _eval = lambda expr, env: _trampoline(_raw_eval(expr, env))
    from .jinja_bridge import get_component_env

--- a/shared/sx/html.py
+++ b/shared/sx/html.py
@@ -28,7 +28,7 @@ import contextvars
 from typing import Any

 from .types import Component, Island, Keyword, Lambda, Macro, NIL, Symbol
-from .evaluator import _eval as _raw_eval, _call_component as _raw_call_component, _expand_macro, _trampoline
+from .ref.sx_ref import eval_expr as _raw_eval, call_component as _raw_call_component, expand_macro as _expand_macro, trampoline as _trampoline

 def _eval(expr, env):
    """Evaluate and unwrap thunks — all html.py _eval calls are non-tail."""
@@ -414,10 +414,10 @@ def _render_component(comp: Component, args: list, env: dict[str, Any]) -> str:
 def _render_island(island: Island, args: list, env: dict[str, Any]) -> str:
    """Render an island as static HTML with hydration attributes.

-    Produces: <span data-sx-island="name" data-sx-state='{"k":"v",...}'>body HTML</span>
-    The client hydrates this into a reactive island.
+    Produces: <span data-sx-island="name" data-sx-state="{:k &quot;v&quot;}">body HTML</span>
+    The client hydrates this into a reactive island via sx-parse (not JSON).
    """
-    import json as _json
+    from .parser import serialize as _sx_serialize

    kwargs: dict[str, Any] = {}
    children: list[Any] = []
@@ -443,26 +443,13 @@ def _render_island(island: Island, args: list, env: dict[str, Any]) -> str:

    body_html = _render(island.body, local)

-    # Serialize state for hydration — only keyword args
-    state = {}
-    for k, v in kwargs.items():
-        if isinstance(v, (str, int, float, bool)):
-            state[k] = v
-        elif v is NIL or v is None:
-            state[k] = None
-        elif isinstance(v, list):
-            state[k] = v
-        elif isinstance(v, dict):
-            state[k] = v
-        else:
-            state[k] = str(v)
-
-    state_json = _escape_attr(_json.dumps(state, separators=(",", ":"))) if state else ""
+    # Serialize state for hydration — SX format (not JSON)
+    state_sx = _escape_attr(_sx_serialize(kwargs)) if kwargs else ""
    island_name = _escape_attr(island.name)

    parts = [f'<span data-sx-island="{island_name}"']
-    if state_json:
-        parts.append(f' data-sx-state="{state_json}"')
+    if state_sx:
+        parts.append(f' data-sx-state="{state_sx}"')
    parts.append(">")
    parts.append(body_html)
    parts.append("</span>")
--- a/shared/sx/jinja_bridge.py
+++ b/shared/sx/jinja_bridge.py
@@ -229,10 +229,7 @@ def register_components(sx_source: str) -> None:
                  (div :class "..." (div :class "..." title)))))
        ''')
    """
-    if _os.environ.get("SX_USE_REF") == "1":
-        from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
-    else:
-        from .evaluator import _eval as _raw_eval, _trampoline
+    from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
    _eval = lambda expr, env: _trampoline(_raw_eval(expr, env))
    from .parser import parse_all
    from .css_registry import scan_classes_from_sx
--- a/shared/sx/pages.py
+++ b/shared/sx/pages.py
@@ -127,7 +127,7 @@ def get_page_helpers(service: str) -> dict[str, Any]:
 def load_page_file(filepath: str, service_name: str) -> list[PageDef]:
    """Parse an .sx file, evaluate it, and register any PageDef values."""
    from .parser import parse_all
-    from .evaluator import _eval as _raw_eval, _trampoline
+    from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
    _eval = lambda expr, env: _trampoline(_raw_eval(expr, env))
    from .jinja_bridge import get_component_env

@@ -170,7 +170,11 @@ async def _eval_slot(expr: Any, env: dict, ctx: Any) -> str:
    Expands component calls (so IO in the body executes) but serializes
    the result as SX wire format, not HTML.
    """
-    from .async_eval import async_eval_slot_to_sx
+    import os
+    if os.environ.get("SX_USE_REF") == "1":
+        from .ref.async_eval_ref import async_eval_slot_to_sx
+    else:
+        from .async_eval import async_eval_slot_to_sx
    return await async_eval_slot_to_sx(expr, env, ctx)


--- a/shared/sx/parser.py
+++ b/shared/sx/parser.py
@@ -41,7 +41,7 @@ def _resolve_sx_reader_macro(name: str):
    """
    try:
        from .jinja_bridge import get_component_env
-        from .evaluator import _trampoline, _call_lambda
+        from .ref.sx_ref import trampoline as _trampoline, call_lambda as _call_lambda
        from .types import Lambda
    except ImportError:
        return None
--- a/shared/sx/query_registry.py
+++ b/shared/sx/query_registry.py
@@ -78,7 +78,7 @@ def clear(service: str | None = None) -> None:
 def load_query_file(filepath: str, service_name: str) -> list[QueryDef]:
    """Parse an .sx file and register any defquery definitions."""
    from .parser import parse_all
-    from .evaluator import _eval as _raw_eval, _trampoline
+    from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
    _eval = lambda expr, env: _trampoline(_raw_eval(expr, env))
    from .jinja_bridge import get_component_env

@@ -103,7 +103,7 @@ def load_query_file(filepath: str, service_name: str) -> list[QueryDef]:
 def load_action_file(filepath: str, service_name: str) -> list[ActionDef]:
    """Parse an .sx file and register any defaction definitions."""
    from .parser import parse_all
-    from .evaluator import _eval as _raw_eval, _trampoline
+    from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
    _eval = lambda expr, env: _trampoline(_raw_eval(expr, env))
    from .jinja_bridge import get_component_env

--- a/shared/sx/ref/adapter-async.sx
+++ b/shared/sx/ref/adapter-async.sx
--- a/shared/sx/ref/adapter-html.sx
+++ b/shared/sx/ref/adapter-html.sx
@@ -433,11 +433,11 @@

        ;; Render the island body as HTML
        (let ((body-html (render-to-html (component-body island) local))
-              (state-json (serialize-island-state kwargs)))
+              (state-sx (serialize-island-state kwargs)))
          ;; Wrap in container with hydration attributes
          (str "<span data-sx-island=\"" (escape-attr island-name) "\""
-               (if state-json
-                 (str " data-sx-state=\"" (escape-attr state-json) "\"")
+               (if state-sx
+                 (str " data-sx-state=\"" (escape-attr state-sx) "\"")
                 "")
               ">"
               body-html
@@ -445,17 +445,17 @@


 ;; --------------------------------------------------------------------------
-;; serialize-island-state — serialize kwargs to JSON for hydration
+;; serialize-island-state — serialize kwargs to SX for hydration
 ;; --------------------------------------------------------------------------
 ;;
-;; Only serializes simple values (numbers, strings, booleans, nil, lists, dicts).
-;; Functions, components, and other non-serializable values are skipped.
+;; Uses the SX serializer (not JSON) so the client can parse with sx-parse.
+;; Handles all SX types natively: numbers, strings, booleans, nil, lists, dicts.

 (define serialize-island-state
  (fn (kwargs)
    (if (empty-dict? kwargs)
      nil
-      (json-serialize kwargs))))
+      (sx-serialize kwargs))))


 ;; --------------------------------------------------------------------------
@@ -476,8 +476,8 @@
 ;; Raw HTML construction:
 ;;   (make-raw-html s)          → wrap string as raw HTML (not double-escaped)
 ;;
-;; JSON serialization (for island state):
-;;   (json-serialize dict)      → JSON string
+;; Island state serialization:
+;;   (sx-serialize val)         → SX source string (from parser.sx)
 ;;   (empty-dict? d)            → boolean
 ;;   (escape-attr s)            → HTML attribute escape
 ;;
--- a/shared/sx/ref/adapter-sx.sx
+++ b/shared/sx/ref/adapter-sx.sx
@@ -106,35 +106,56 @@
 (define aser-fragment
  (fn (children env)
    ;; Serialize (<> child1 child2 ...) to sx source string
-    (let ((parts (filter
-                   (fn (x) (not (nil? x)))
-                   (map (fn (c) (aser c env)) children))))
+    ;; Must flatten list results (e.g. from map/filter) to avoid nested parens
+    (let ((parts (list)))
+      (for-each
+        (fn (c)
+          (let ((result (aser c env)))
+            (if (= (type-of result) "list")
+              (for-each
+                (fn (item)
+                  (when (not (nil? item))
+                    (append! parts (serialize item))))
+                result)
+              (when (not (nil? result))
+                (append! parts (serialize result))))))
+        children)
      (if (empty? parts)
        ""
-        (str "(<> " (join " " (map serialize parts)) ")")))))
+        (str "(<> " (join " " parts) ")")))))


 (define aser-call
  (fn (name args env)
    ;; Serialize (name :key val child ...) — evaluate args but keep as sx
-    (let ((parts (list name)))
-      (reduce
-        (fn (state arg)
-          (let ((skip (get state "skip")))
-            (if skip
-              (assoc state "skip" false "i" (inc (get state "i")))
-              (if (and (= (type-of arg) "keyword")
-                       (< (inc (get state "i")) (len args)))
-                (let ((val (aser (nth args (inc (get state "i"))) env)))
-                  (when (not (nil? val))
-                    (append! parts (str ":" (keyword-name arg)))
-                    (append! parts (serialize val)))
-                  (assoc state "skip" true "i" (inc (get state "i"))))
-                (let ((val (aser arg env)))
-                  (when (not (nil? val))
-                    (append! parts (serialize val)))
-                  (assoc state "i" (inc (get state "i"))))))))
-        (dict "i" 0 "skip" false)
+    ;; Uses for-each + mutable state (not reduce) so bootstrapper emits for-loops
+    ;; that can contain nested for-each for list flattening.
+    (let ((parts (list name))
+          (skip false)
+          (i 0))
+      (for-each
+        (fn (arg)
+          (if skip
+            (do (set! skip false)
+                (set! i (inc i)))
+            (if (and (= (type-of arg) "keyword")
+                     (< (inc i) (len args)))
+              (let ((val (aser (nth args (inc i)) env)))
+                (when (not (nil? val))
+                  (append! parts (str ":" (keyword-name arg)))
+                  (append! parts (serialize val)))
+                (set! skip true)
+                (set! i (inc i)))
+              (let ((val (aser arg env)))
+                (when (not (nil? val))
+                  (if (= (type-of val) "list")
+                    (for-each
+                      (fn (item)
+                        (when (not (nil? item))
+                          (append! parts (serialize item))))
+                      val)
+                    (append! parts (serialize val))))
+                (set! i (inc i))))))
        args)
      (str "(" (join " " parts) ")"))))

--- a/shared/sx/ref/async_eval_ref.py
+++ b/shared/sx/ref/async_eval_ref.py
--- a/shared/sx/ref/boot.sx
+++ b/shared/sx/ref/boot.sx
@@ -344,15 +344,15 @@
 (define hydrate-island
  (fn (el)
    (let ((name (dom-get-attr el "data-sx-island"))
-          (state-json (or (dom-get-attr el "data-sx-state") "{}")))
+          (state-sx (or (dom-get-attr el "data-sx-state") "{}")))
      (let ((comp-name (str "~" name))
            (env (get-render-env nil)))
        (let ((comp (env-get env comp-name)))
          (if (not (or (component? comp) (island? comp)))
            (log-warn (str "hydrate-island: unknown island " comp-name))

-            ;; Parse state and build keyword args
-            (let ((kwargs (json-parse state-json))
+            ;; Parse state and build keyword args — SX format, not JSON
+            (let ((kwargs (or (first (sx-parse state-sx)) {}))
                  (disposers (list))
                  (local (env-merge (component-closure comp) env)))

@@ -494,8 +494,8 @@
 ;;   (log-info msg)                → void (console.log with prefix)
 ;;   (log-parse-error label text err) → void (diagnostic parse error)
 ;;
-;; === JSON ===
-;;   (json-parse str)              → dict/list/value (JSON.parse)
+;; === Parsing (island state) ===
+;;   (sx-parse str)                → list of AST expressions (from parser.sx)
 ;;
 ;; === Processing markers ===
 ;;   (mark-processed! el key)      → void
--- a/shared/sx/ref/bootstrap_py.py
+++ b/shared/sx/ref/bootstrap_py.py
@@ -49,6 +49,8 @@ class PyEmitter:

    def __init__(self):
        self.indent = 0
+        self._async_names: set[str] = set()  # SX names of define-async functions
+        self._in_async: bool = False          # Currently emitting async def body?

    def emit(self, expr) -> str:
        """Emit a Python expression from an SX AST node."""
@@ -80,6 +82,8 @@ class PyEmitter:
                name = head.name
                if name == "define":
                    return self._emit_define(expr, indent)
+                if name == "define-async":
+                    return self._emit_define_async(expr, indent)
                if name == "set!":
                    return f"{pad}{self._mangle(expr[1].name)} = {self.emit(expr[2])}"
                if name == "when":
@@ -275,6 +279,19 @@ class PyEmitter:
            "sf-defisland": "sf_defisland",
            # adapter-sx.sx
            "render-to-sx": "render_to_sx",
+            # adapter-async.sx platform primitives
+            "svg-context-set!": "svg_context_set",
+            "svg-context-reset!": "svg_context_reset",
+            "css-class-collect!": "css_class_collect",
+            "is-raw-html?": "is_raw_html",
+            "async-coroutine?": "is_async_coroutine",
+            "async-await!": "async_await",
+            "is-sx-expr?": "is_sx_expr",
+            "sx-expr?": "is_sx_expr",
+            "io-primitive?": "io_primitive_p",
+            "expand-components?": "expand_components_p",
+            "svg-context?": "svg_context_p",
+            "make-sx-expr": "make_sx_expr",
            "aser": "aser",
            "eval-case-aser": "eval_case_aser",
            "sx-serialize": "sx_serialize",
@@ -417,6 +434,8 @@ class PyEmitter:
        # Regular function call
        fn_name = self._mangle(name)
        args = ", ".join(self.emit(x) for x in expr[1:])
+        if self._in_async and name in self._async_names:
+            return f"(await {fn_name}({args}))"
        return f"{fn_name}({args})"

    # --- Special form emitters ---
@@ -513,13 +532,16 @@ class PyEmitter:
        body_parts = expr[2:]
        lines = [f"{pad}if sx_truthy({cond}):"]
        for b in body_parts:
-            lines.append(self.emit_statement(b, indent + 1))
+            self._emit_stmt_recursive(b, lines, indent + 1)
        return "\n".join(lines)

    def _emit_cond(self, expr) -> str:
        clauses = expr[1:]
        if not clauses:
            return "NIL"
+        # Check ALL clauses are 2-element lists (scheme-style).
+        # Checking only the first is ambiguous — (nil? x) is a 2-element
+        # function call, not a scheme clause ((test body)).
        is_scheme = (
            all(isinstance(c, list) and len(c) == 2 for c in clauses)
            and not any(isinstance(c, Keyword) for c in clauses)
@@ -642,6 +664,16 @@ class PyEmitter:
        val = self.emit(val_expr)
        return f"{pad}{self._mangle(name)} = {val}"

+    def _emit_define_async(self, expr, indent: int = 0) -> str:
+        """Emit a define-async form as an async def statement."""
+        name = expr[1].name if isinstance(expr[1], Symbol) else str(expr[1])
+        val_expr = expr[2]
+        if (isinstance(val_expr, list) and val_expr and
+                isinstance(val_expr[0], Symbol) and val_expr[0].name in ("fn", "lambda")):
+            return self._emit_define_as_def(name, val_expr, indent, is_async=True)
+        # Shouldn't happen — define-async should always wrap fn/lambda
+        return self._emit_define(expr, indent)
+
    def _body_uses_set(self, fn_expr) -> bool:
        """Check if a fn expression's body (recursively) uses set!."""
        def _has_set(node):
@@ -654,12 +686,16 @@ class PyEmitter:
        body = fn_expr[2:]
        return any(_has_set(b) for b in body)

-    def _emit_define_as_def(self, name: str, fn_expr, indent: int = 0) -> str:
+    def _emit_define_as_def(self, name: str, fn_expr, indent: int = 0,
+                            is_async: bool = False) -> str:
        """Emit a define with fn value as a proper def statement.

        This is used for functions that contain set! — Python closures can't
        rebind outer lambda params, so we need proper def + local variables.
        Variables mutated by set! from nested lambdas use a _cells dict.
+
+        When is_async=True, emits 'async def' and sets _in_async so that
+        calls to other async functions receive 'await'.
        """
        pad = "    " * indent
        params = fn_expr[1]
@@ -686,14 +722,19 @@ class PyEmitter:
        py_name = self._mangle(name)
        # Find set! target variables that are used from nested lambda scopes
        nested_set_vars = self._find_nested_set_vars(body)
-        lines = [f"{pad}def {py_name}({params_str}):"]
+        def_kw = "async def" if is_async else "def"
+        lines = [f"{pad}{def_kw} {py_name}({params_str}):"]
        if nested_set_vars:
            lines.append(f"{pad}    _cells = {{}}")
-        # Emit body with cell var tracking
+        # Emit body with cell var tracking (and async context if needed)
        old_cells = getattr(self, '_current_cell_vars', set())
+        old_async = self._in_async
        self._current_cell_vars = nested_set_vars
+        if is_async:
+            self._in_async = True
        self._emit_body_stmts(body, lines, indent + 1)
        self._current_cell_vars = old_cells
+        self._in_async = old_async
        return "\n".join(lines)

    def _find_nested_set_vars(self, body) -> set[str]:
@@ -750,7 +791,7 @@ class PyEmitter:
            if is_last:
                self._emit_return_expr(expr, lines, indent)
            else:
-                lines.append(self.emit_statement(expr, indent))
+                self._emit_stmt_recursive(expr, lines, indent)

    def _emit_return_expr(self, expr, lines: list, indent: int) -> None:
        """Emit an expression in return position, flattening control flow."""
@@ -775,6 +816,11 @@ class PyEmitter:
            if name in ("do", "begin"):
                self._emit_body_stmts(expr[1:], lines, indent)
                return
+            if name == "for-each":
+                # for-each in return position: emit as statement, return NIL
+                lines.append(self._emit_for_each_stmt(expr, indent))
+                lines.append(f"{pad}return NIL")
+                return
        lines.append(f"{pad}return {self.emit(expr)}")

    def _emit_if_return(self, expr, lines: list, indent: int) -> None:
@@ -1034,12 +1080,15 @@ class PyEmitter:
 # ---------------------------------------------------------------------------

 def extract_defines(source: str) -> list[tuple[str, list]]:
-    """Parse .sx source, return list of (name, define-expr) for top-level defines."""
+    """Parse .sx source, return list of (name, define-expr) for top-level defines.
+
+    Extracts both (define ...) and (define-async ...) forms.
+    """
    exprs = parse_all(source)
    defines = []
    for expr in exprs:
        if isinstance(expr, list) and expr and isinstance(expr[0], Symbol):
-            if expr[0].name == "define":
+            if expr[0].name in ("define", "define-async"):
                name = expr[1].name if isinstance(expr[1], Symbol) else str(expr[1])
                defines.append((name, expr))
    return defines
@@ -1196,6 +1245,8 @@ def compile_ref_to_py(
            spec_mod_set.add("deps")
        if "signals" in SPEC_MODULES:
            spec_mod_set.add("signals")
+        if "page-helpers" in SPEC_MODULES:
+            spec_mod_set.add("page-helpers")
    has_deps = "deps" in spec_mod_set

    # Core files always included, then selected adapters, then spec modules
@@ -1210,6 +1261,28 @@ def compile_ref_to_py(
    for name in sorted(spec_mod_set):
        sx_files.append(SPEC_MODULES[name])

+    # Pre-scan define-async names (needed before transpilation so emitter
+    # knows which calls require 'await')
+    has_async = "async" in adapter_set
+    if has_async:
+        async_filename = ADAPTER_FILES["async"][0]
+        async_filepath = os.path.join(ref_dir, async_filename)
+        if os.path.exists(async_filepath):
+            with open(async_filepath) as f:
+                async_src = f.read()
+            for aexpr in parse_all(async_src):
+                if (isinstance(aexpr, list) and aexpr
+                        and isinstance(aexpr[0], Symbol)
+                        and aexpr[0].name == "define-async"):
+                    aname = aexpr[1].name if isinstance(aexpr[1], Symbol) else str(aexpr[1])
+                    emitter._async_names.add(aname)
+            # Platform async primitives (provided by host, also need await)
+            emitter._async_names.update({
+                "async-eval", "execute-io", "async-await!",
+            })
+        # Async adapter is transpiled last (after sync adapters)
+        sx_files.append(ADAPTER_FILES["async"])
+
    all_sections = []
    for filename, label in sx_files:
        filepath = os.path.join(ref_dir, filename)
@@ -1246,6 +1319,9 @@ def compile_ref_to_py(
    if has_deps:
        parts.append(PLATFORM_DEPS_PY)

+    if has_async:
+        parts.append(PLATFORM_ASYNC_PY)
+
    for label, defines in all_sections:
        parts.append(f"\n# === Transpiled from {label} ===\n")
        for name, expr in defines:
@@ -1256,7 +1332,7 @@ def compile_ref_to_py(
    parts.append(FIXUPS_PY)
    if has_continuations:
        parts.append(CONTINUATIONS_PY)
-    parts.append(public_api_py(has_html, has_sx, has_deps))
+    parts.append(public_api_py(has_html, has_sx, has_deps, has_async))
    return "\n".join(parts)


--- a/shared/sx/ref/bootstrap_test.py
+++ b/shared/sx/ref/bootstrap_test.py
@@ -143,7 +143,7 @@ def _emit_py(suites: list[dict], preamble: list) -> str:
    lines.append('')
    lines.append('import pytest')
    lines.append('from shared.sx.parser import parse_all')
-    lines.append('from shared.sx.evaluator import _eval, _trampoline')
+    lines.append('from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline')
    lines.append('')
    lines.append('')
    lines.append(f"_PREAMBLE = '''{preamble_escaped}'''")
--- a/shared/sx/ref/engine.sx
+++ b/shared/sx/ref/engine.sx
@@ -34,11 +34,12 @@
 (define parse-time
  (fn (s)
    ;; Parse time string: "2s" → 2000, "500ms" → 500
-    (cond
-      (nil? s) 0
-      (ends-with? s "ms") (parse-int s 0)
-      (ends-with? s "s")  (* (parse-int (replace s "s" "") 0) 1000)
-      :else (parse-int s 0))))
+    ;; Uses nested if (not cond) because cond misclassifies 2-element
+    ;; function calls like (nil? s) as scheme-style ((test body)) clauses.
+    (if (nil? s) 0
+      (if (ends-with? s "ms") (parse-int s 0)
+        (if (ends-with? s "s") (* (parse-int (replace s "s" "") 0) 1000)
+          (parse-int s 0))))))


 (define parse-trigger-spec
@@ -219,20 +220,19 @@
    ;; Filter form parameters by sx-params spec.
    ;; all-params is a list of (key value) pairs.
    ;; Returns filtered list of (key value) pairs.
-    (cond
-      (nil? params-spec) all-params
-      (= params-spec "none") (list)
-      (= params-spec "*") all-params
-      (starts-with? params-spec "not ")
-        (let ((excluded (map trim (split (slice params-spec 4) ","))))
-          (filter
-            (fn (p) (not (contains? excluded (first p))))
-            all-params))
-      :else
-        (let ((allowed (map trim (split params-spec ","))))
-          (filter
-            (fn (p) (contains? allowed (first p)))
-            all-params)))))
+    ;; Uses nested if (not cond) — see parse-time comment.
+    (if (nil? params-spec) all-params
+      (if (= params-spec "none") (list)
+        (if (= params-spec "*") all-params
+          (if (starts-with? params-spec "not ")
+            (let ((excluded (map trim (split (slice params-spec 4) ","))))
+              (filter
+                (fn (p) (not (contains? excluded (first p))))
+                all-params))
+            (let ((allowed (map trim (split params-spec ","))))
+              (filter
+                (fn (p) (contains? allowed (first p)))
+                all-params))))))))


 ;; --------------------------------------------------------------------------
--- a/shared/sx/ref/eval.sx
+++ b/shared/sx/ref/eval.sx
@@ -309,14 +309,18 @@
        nil))))


+;; cond-scheme? — check if ALL clauses are 2-element lists (scheme-style).
+;; Checking only the first arg is ambiguous — (nil? x) is a 2-element
+;; function call, not a scheme clause ((test body)).
+(define cond-scheme?
+  (fn (clauses)
+    (every? (fn (c) (and (= (type-of c) "list") (= (len c) 2)))
+            clauses)))
+
 (define sf-cond
  (fn (args env)
-    ;; Detect scheme-style: first arg is a 2-element list
-    (if (and (= (type-of (first args)) "list")
-             (= (len (first args)) 2))
-      ;; Scheme-style: ((test body) ...)
+    (if (cond-scheme? args)
      (sf-cond-scheme args env)
-      ;; Clojure-style: test body test body ...
      (sf-cond-clojure args env))))

 (define sf-cond-scheme
--- a/shared/sx/ref/js.sx
+++ b/shared/sx/ref/js.sx
@@ -1290,8 +1290,9 @@
          (= name "append!")
            (str (js-expr (nth expr 1)) ".push(" (js-expr (nth expr 2)) ");")
          (= name "env-set!")
-            (str (js-expr (nth expr 1)) "[" (js-expr (nth expr 2))
-                 "] = " (js-expr (nth expr 3)) ";")
+            (str "envSet(" (js-expr (nth expr 1))
+                 ", " (js-expr (nth expr 2))
+                 ", " (js-expr (nth expr 3)) ");")
          (= name "set-lambda-name!")
            (str (js-expr (nth expr 1)) ".name = " (js-expr (nth expr 2)) ";")
          :else
--- a/shared/sx/ref/page-helpers.sx
+++ b/shared/sx/ref/page-helpers.sx
@@ -0,0 +1,368 @@
+;; ==========================================================================
+;; page-helpers.sx — Pure data-transformation page helpers
+;;
+;; These functions take raw data (from Python I/O edge) and return
+;; structured dicts for page rendering. No I/O — pure transformations
+;; only. Bootstrapped to every host.
+;; ==========================================================================
+
+
+;; --------------------------------------------------------------------------
+;; categorize-special-forms
+;;
+;; Parses define-special-form declarations from special-forms.sx AST,
+;; categorizes each form by name lookup, returns dict of category → forms.
+;; --------------------------------------------------------------------------
+
+(define special-form-category-map
+  {"if" "Control Flow" "when" "Control Flow" "cond" "Control Flow"
+   "case" "Control Flow" "and" "Control Flow" "or" "Control Flow"
+   "let" "Binding" "let*" "Binding" "letrec" "Binding"
+   "define" "Binding" "set!" "Binding"
+   "lambda" "Functions & Components" "fn" "Functions & Components"
+   "defcomp" "Functions & Components" "defmacro" "Functions & Components"
+   "begin" "Sequencing & Threading" "do" "Sequencing & Threading"
+   "->" "Sequencing & Threading"
+   "quote" "Quoting" "quasiquote" "Quoting"
+   "reset" "Continuations" "shift" "Continuations"
+   "dynamic-wind" "Guards"
+   "map" "Higher-Order Forms" "map-indexed" "Higher-Order Forms"
+   "filter" "Higher-Order Forms" "reduce" "Higher-Order Forms"
+   "some" "Higher-Order Forms" "every?" "Higher-Order Forms"
+   "for-each" "Higher-Order Forms"
+   "defstyle" "Domain Definitions"
+   "defhandler" "Domain Definitions" "defpage" "Domain Definitions"
+   "defquery" "Domain Definitions" "defaction" "Domain Definitions"})
+
+
+(define extract-define-kwargs
+  (fn (expr)
+    ;; Extract keyword args from a define-special-form expression.
+    ;; Returns dict of keyword-name → string value.
+    ;; Walks items pairwise: when item[i] is a keyword, item[i+1] is its value.
+    (let ((result {})
+          (items (slice expr 2))
+          (n (len items)))
+      (for-each
+        (fn (idx)
+          (when (and (< (+ idx 1) n)
+                     (= (type-of (nth items idx)) "keyword"))
+            (let ((key (keyword-name (nth items idx)))
+                  (val (nth items (+ idx 1))))
+              (dict-set! result key
+                (if (= (type-of val) "list")
+                  (str "(" (join " " (map serialize val)) ")")
+                  (str val))))))
+        (range 0 n))
+      result)))
+
+
+(define categorize-special-forms
+  (fn (parsed-exprs)
+    ;; parsed-exprs: result of parse-all on special-forms.sx
+    ;; Returns dict of category-name → list of form dicts.
+    (let ((categories {}))
+      (for-each
+        (fn (expr)
+          (when (and (= (type-of expr) "list")
+                     (>= (len expr) 2)
+                     (= (type-of (first expr)) "symbol")
+                     (= (symbol-name (first expr)) "define-special-form"))
+            (let ((name (nth expr 1))
+                  (kwargs (extract-define-kwargs expr))
+                  (category (or (get special-form-category-map name) "Other")))
+              (when (not (has-key? categories category))
+                (dict-set! categories category (list)))
+              (append! (get categories category)
+                {"name" name
+                 "syntax" (or (get kwargs "syntax") "")
+                 "doc" (or (get kwargs "doc") "")
+                 "tail-position" (or (get kwargs "tail-position") "")
+                 "example" (or (get kwargs "example") "")}))))
+        parsed-exprs)
+      categories)))
+
+
+;; --------------------------------------------------------------------------
+;; build-reference-data
+;;
+;; Takes a slug and raw reference data, returns structured dict for rendering.
+;; --------------------------------------------------------------------------
+
+(define build-ref-items-with-href
+  (fn (items base-path detail-keys n-fields)
+    ;; items: list of lists (tuples), each with n-fields elements
+    ;; base-path: e.g. "/hypermedia/reference/attributes/"
+    ;; detail-keys: list of strings (keys that have detail pages)
+    ;; n-fields: 2 or 3 (number of fields per tuple)
+    (map
+      (fn (item)
+        (if (= n-fields 3)
+          ;; [name, desc/value, exists/desc]
+          (let ((name (nth item 0))
+                (field2 (nth item 1))
+                (field3 (nth item 2)))
+            {"name" name
+             "desc" field2
+             "exists" field3
+             "href" (if (and field3 (some (fn (k) (= k name)) detail-keys))
+                      (str base-path name)
+                      nil)})
+          ;; [name, desc]
+          (let ((name (nth item 0))
+                (desc (nth item 1)))
+            {"name" name
+             "desc" desc
+             "href" (if (some (fn (k) (= k name)) detail-keys)
+                      (str base-path name)
+                      nil)})))
+      items)))
+
+
+(define build-reference-data
+  (fn (slug raw-data detail-keys)
+    ;; slug: "attributes", "headers", "events", "js-api"
+    ;; raw-data: dict with the raw data lists for this slug
+    ;; detail-keys: list of names that have detail pages
+    (case slug
+      "attributes"
+        {"req-attrs" (build-ref-items-with-href
+                       (get raw-data "req-attrs")
+                       "/hypermedia/reference/attributes/" detail-keys 3)
+         "beh-attrs" (build-ref-items-with-href
+                       (get raw-data "beh-attrs")
+                       "/hypermedia/reference/attributes/" detail-keys 3)
+         "uniq-attrs" (build-ref-items-with-href
+                        (get raw-data "uniq-attrs")
+                        "/hypermedia/reference/attributes/" detail-keys 3)}
+
+      "headers"
+        {"req-headers" (build-ref-items-with-href
+                         (get raw-data "req-headers")
+                         "/hypermedia/reference/headers/" detail-keys 3)
+         "resp-headers" (build-ref-items-with-href
+                          (get raw-data "resp-headers")
+                          "/hypermedia/reference/headers/" detail-keys 3)}
+
+      "events"
+        {"events-list" (build-ref-items-with-href
+                         (get raw-data "events-list")
+                         "/hypermedia/reference/events/" detail-keys 2)}
+
+      "js-api"
+        {"js-api-list" (map (fn (item) {"name" (nth item 0) "desc" (nth item 1)})
+                            (get raw-data "js-api-list"))}
+
+      ;; default: attributes
+      :else
+        {"req-attrs" (build-ref-items-with-href
+                       (get raw-data "req-attrs")
+                       "/hypermedia/reference/attributes/" detail-keys 3)
+         "beh-attrs" (build-ref-items-with-href
+                       (get raw-data "beh-attrs")
+                       "/hypermedia/reference/attributes/" detail-keys 3)
+         "uniq-attrs" (build-ref-items-with-href
+                        (get raw-data "uniq-attrs")
+                        "/hypermedia/reference/attributes/" detail-keys 3)})))
+
+
+;; --------------------------------------------------------------------------
+;; build-attr-detail / build-header-detail / build-event-detail
+;;
+;; Lookup a slug in a detail dict, reshape for page rendering.
+;; --------------------------------------------------------------------------
+
+(define build-attr-detail
+  (fn (slug detail)
+    ;; detail: dict with "description", "example", "handler", "demo" keys or nil
+    (if (nil? detail)
+      {"attr-not-found" true}
+      {"attr-not-found" nil
+       "attr-title" slug
+       "attr-description" (get detail "description")
+       "attr-example" (get detail "example")
+       "attr-handler" (get detail "handler")
+       "attr-demo" (get detail "demo")
+       "attr-wire-id" (if (has-key? detail "handler")
+                        (str "ref-wire-"
+                          (replace (replace slug ":" "-") "*" "star"))
+                        nil)})))
+
+
+(define build-header-detail
+  (fn (slug detail)
+    (if (nil? detail)
+      {"header-not-found" true}
+      {"header-not-found" nil
+       "header-title" slug
+       "header-direction" (get detail "direction")
+       "header-description" (get detail "description")
+       "header-example" (get detail "example")
+       "header-demo" (get detail "demo")})))
+
+
+(define build-event-detail
+  (fn (slug detail)
+    (if (nil? detail)
+      {"event-not-found" true}
+      {"event-not-found" nil
+       "event-title" slug
+       "event-description" (get detail "description")
+       "event-example" (get detail "example")
+       "event-demo" (get detail "demo")})))
+
+
+;; --------------------------------------------------------------------------
+;; build-component-source
+;;
+;; Reconstruct defcomp/defisland source from component metadata.
+;; --------------------------------------------------------------------------
+
+(define build-component-source
+  (fn (comp-data)
+    ;; comp-data: dict with "type", "name", "params", "has-children", "body-sx", "affinity"
+    (let ((comp-type (get comp-data "type"))
+          (name (get comp-data "name"))
+          (params (get comp-data "params"))
+          (has-children (get comp-data "has-children"))
+          (body-sx (get comp-data "body-sx"))
+          (affinity (get comp-data "affinity")))
+      (if (= comp-type "not-found")
+        (str ";; component " name " not found")
+        (let ((param-strs (if (empty? params)
+                            (if has-children
+                              (list "&rest" "children")
+                              (list))
+                            (if has-children
+                              (append (cons "&key" params) (list "&rest" "children"))
+                              (cons "&key" params))))
+              (params-sx (str "(" (join " " param-strs) ")"))
+              (form-name (if (= comp-type "island") "defisland" "defcomp"))
+              (affinity-str (if (and (= comp-type "component")
+                                     (not (nil? affinity))
+                                     (not (= affinity "auto")))
+                              (str " :affinity " affinity)
+                              "")))
+          (str "(" form-name " " name " " params-sx affinity-str "\n  " body-sx ")"))))))
+
+
+;; --------------------------------------------------------------------------
+;; build-bundle-analysis
+;;
+;; Compute per-page bundle stats from pre-extracted component data.
+;; --------------------------------------------------------------------------
+
+(define build-bundle-analysis
+  (fn (pages-raw components-raw total-components total-macros pure-count io-count)
+    ;; pages-raw: list of {:name :path :direct :needed-names}
+    ;; components-raw: dict of name → {:is-pure :affinity :render-target :io-refs :deps :source}
+    (let ((pages-data (list)))
+      (for-each
+        (fn (page)
+          (let ((needed-names (get page "needed-names"))
+                (n (len needed-names))
+                (pct (if (> total-components 0)
+                       (round (* (/ n total-components) 100))
+                       0))
+                (savings (- 100 pct))
+                (pure-in-page 0)
+                (io-in-page 0)
+                (page-io-refs (list))
+                (comp-details (list)))
+            ;; Walk needed components
+            (for-each
+              (fn (comp-name)
+                (let ((info (get components-raw comp-name)))
+                  (when (not (nil? info))
+                    (if (get info "is-pure")
+                      (set! pure-in-page (+ pure-in-page 1))
+                      (do
+                        (set! io-in-page (+ io-in-page 1))
+                        (for-each
+                          (fn (ref) (when (not (some (fn (r) (= r ref)) page-io-refs))
+                                      (append! page-io-refs ref)))
+                          (or (get info "io-refs") (list)))))
+                    (append! comp-details
+                      {"name" comp-name
+                       "is-pure" (get info "is-pure")
+                       "affinity" (get info "affinity")
+                       "render-target" (get info "render-target")
+                       "io-refs" (or (get info "io-refs") (list))
+                       "deps" (or (get info "deps") (list))
+                       "source" (get info "source")}))))
+              needed-names)
+            (append! pages-data
+              {"name" (get page "name")
+               "path" (get page "path")
+               "direct" (get page "direct")
+               "needed" n
+               "pct" pct
+               "savings" savings
+               "io-refs" (len page-io-refs)
+               "pure-in-page" pure-in-page
+               "io-in-page" io-in-page
+               "components" comp-details})))
+        pages-raw)
+      {"pages" pages-data
+       "total-components" total-components
+       "total-macros" total-macros
+       "pure-count" pure-count
+       "io-count" io-count})))
+
+
+;; --------------------------------------------------------------------------
+;; build-routing-analysis
+;;
+;; Classify pages by routing mode (client vs server).
+;; --------------------------------------------------------------------------
+
+(define build-routing-analysis
+  (fn (pages-raw)
+    ;; pages-raw: list of {:name :path :has-data :content-src}
+    (let ((pages-data (list))
+          (client-count 0)
+          (server-count 0))
+      (for-each
+        (fn (page)
+          (let ((has-data (get page "has-data"))
+                (content-src (or (get page "content-src") ""))
+                (mode nil)
+                (reason ""))
+            (cond
+              has-data
+                (do (set! mode "server")
+                    (set! reason "Has :data expression — needs server IO")
+                    (set! server-count (+ server-count 1)))
+              (empty? content-src)
+                (do (set! mode "server")
+                    (set! reason "No content expression")
+                    (set! server-count (+ server-count 1)))
+              :else
+                (do (set! mode "client")
+                    (set! client-count (+ client-count 1))))
+            (append! pages-data
+              {"name" (get page "name")
+               "path" (get page "path")
+               "mode" mode
+               "has-data" has-data
+               "content-expr" (if (> (len content-src) 80)
+                                (str (slice content-src 0 80) "...")
+                                content-src)
+               "reason" reason})))
+        pages-raw)
+      {"pages" pages-data
+       "total-pages" (+ client-count server-count)
+       "client-count" client-count
+       "server-count" server-count})))
+
+
+;; --------------------------------------------------------------------------
+;; build-affinity-analysis
+;;
+;; Package component affinity info + page render plans for display.
+;; --------------------------------------------------------------------------
+
+(define build-affinity-analysis
+  (fn (demo-components page-plans)
+    {"components" demo-components
+     "page-plans" page-plans}))
--- a/shared/sx/ref/platform_js.py
+++ b/shared/sx/ref/platform_js.py
--- a/shared/sx/ref/platform_py.py
+++ b/shared/sx/ref/platform_py.py
@@ -470,10 +470,7 @@ def invoke(f, *args):

 def json_serialize(obj):
    import json
-    try:
-        return json.dumps(obj)
-    except (TypeError, ValueError):
-        return "{}"
+    return json.dumps(obj)


 def is_empty_dict(d):
@@ -608,7 +605,7 @@ def sx_expr_source(x):


 try:
-    from shared.sx.evaluator import EvalError
+    from shared.sx.types import EvalError
 except ImportError:
    class EvalError(Exception):
        pass
@@ -1075,10 +1072,19 @@ import inspect

 from shared.sx.primitives_io import (
    IO_PRIMITIVES, RequestContext, execute_io,
-    css_class_collector as _css_class_collector_cv,
-    _svg_context as _svg_context_cv,
 )

+# Lazy imports to avoid circular dependency (html.py imports sx_ref.py)
+_css_class_collector_cv = None
+_svg_context_cv = None
+
+def _ensure_html_imports():
+    global _css_class_collector_cv, _svg_context_cv
+    if _css_class_collector_cv is None:
+        from shared.sx.html import css_class_collector, _svg_context
+        _css_class_collector_cv = css_class_collector
+        _svg_context_cv = _svg_context
+
 # When True, async_aser expands known components server-side
 _expand_components_cv: contextvars.ContextVar[bool] = contextvars.ContextVar(
    "_expand_components_ref", default=False
@@ -1102,18 +1108,22 @@ def expand_components_p():


 def svg_context_p():
+    _ensure_html_imports()
    return _svg_context_cv.get(False)


 def svg_context_set(val):
+    _ensure_html_imports()
    return _svg_context_cv.set(val)


 def svg_context_reset(token):
+    _ensure_html_imports()
    _svg_context_cv.reset(token)


 def css_class_collect(val):
+    _ensure_html_imports()
    collector = _css_class_collector_cv.get(None)
    if collector is not None:
        collector.update(str(val).split())
@@ -1131,6 +1141,25 @@ def is_sx_expr(x):
    return isinstance(x, SxExpr)


+# Predicate helpers used by adapter-async (these are in PRIMITIVES but
+# the bootstrapped code calls them as plain functions)
+def string_p(x):
+    return isinstance(x, str)
+
+
+def list_p(x):
+    return isinstance(x, _b_list)
+
+
+def number_p(x):
+    return isinstance(x, (int, float)) and not isinstance(x, bool)
+
+
+def sx_parse(src):
+    from shared.sx.parser import parse_all
+    return parse_all(src)
+
+
 def is_async_coroutine(x):
    return inspect.iscoroutine(x)

@@ -1207,48 +1236,16 @@ async def async_eval_slot_to_sx(expr, env, ctx=None):
        ctx = RequestContext()
    token = _expand_components_cv.set(True)
    try:
-        return await _eval_slot_inner(expr, env, ctx)
+        result = await async_eval_slot_inner(expr, env, ctx)
+        if isinstance(result, SxExpr):
+            return result
+        if result is None or result is NIL:
+            return SxExpr("")
+        if isinstance(result, str):
+            return SxExpr(result)
+        return SxExpr(sx_serialize(result))
    finally:
        _expand_components_cv.reset(token)
-
-
-async def _eval_slot_inner(expr, env, ctx):
-    if isinstance(expr, list) and expr:
-        head = expr[0]
-        if isinstance(head, Symbol) and head.name.startswith("~"):
-            comp = env.get(head.name)
-            if isinstance(comp, Component):
-                result = await async_aser_component(comp, expr[1:], env, ctx)
-                if isinstance(result, SxExpr):
-                    return result
-                if result is None or result is NIL:
-                    return SxExpr("")
-                if isinstance(result, str):
-                    return SxExpr(result)
-                return SxExpr(sx_serialize(result))
-    result = await async_aser(expr, env, ctx)
-    result = await _maybe_expand_component_result(result, env, ctx)
-    if isinstance(result, SxExpr):
-        return result
-    if result is None or result is NIL:
-        return SxExpr("")
-    if isinstance(result, str):
-        return SxExpr(result)
-    return SxExpr(sx_serialize(result))
-
-
-async def _maybe_expand_component_result(result, env, ctx):
-    raw = None
-    if isinstance(result, SxExpr):
-        raw = str(result).strip()
-    elif isinstance(result, str):
-        raw = result.strip()
-    if raw and raw.startswith("(~"):
-        from shared.sx.parser import parse_all as _pa
-        parsed = _pa(raw)
-        if parsed:
-            return await async_eval_slot_to_sx(parsed[0], env, ctx)
-    return result
 '''

 # ---------------------------------------------------------------------------
@@ -1374,7 +1371,8 @@ aser_special = _aser_special_with_continuations
 # Public API generator
 # ---------------------------------------------------------------------------

-def public_api_py(has_html: bool, has_sx: bool, has_deps: bool = False) -> str:
+def public_api_py(has_html: bool, has_sx: bool, has_deps: bool = False,
+                  has_async: bool = False) -> str:
    lines = [
        '',
        '# =========================================================================',
@@ -1427,8 +1425,9 @@ def public_api_py(has_html: bool, has_sx: bool, has_deps: bool = False) -> str:
 # ---------------------------------------------------------------------------

 ADAPTER_FILES = {
-    "html": ("adapter-html.sx", "adapter-html"),
-    "sx":   ("adapter-sx.sx",   "adapter-sx"),
+    "html":  ("adapter-html.sx",  "adapter-html"),
+    "sx":    ("adapter-sx.sx",    "adapter-sx"),
+    "async": ("adapter-async.sx", "adapter-async"),
 }

 SPEC_MODULES = {
@@ -1436,6 +1435,7 @@ SPEC_MODULES = {
    "router": ("router.sx", "router (client-side route matching)"),
    "engine": ("engine.sx", "engine (fetch/swap/trigger pure logic)"),
    "signals": ("signals.sx", "signals (reactive signal runtime)"),
+    "page-helpers": ("page-helpers.sx", "page-helpers (pure data transformation helpers)"),
    "types": ("types.sx", "types (gradual type system)"),
 }

--- a/shared/sx/ref/reader_z3.py
+++ b/shared/sx/ref/reader_z3.py
@@ -39,7 +39,7 @@ def _get_z3_env() -> dict[str, Any]:
        return _z3_env

    from shared.sx.parser import parse_all
-    from shared.sx.evaluator import make_env, _eval, _trampoline
+    from shared.sx.ref.sx_ref import make_env, eval_expr as _eval, trampoline as _trampoline

    env = make_env()
    z3_path = os.path.join(os.path.dirname(__file__), "z3.sx")
@@ -60,7 +60,7 @@ def z3_translate(expr: Any) -> str:

    Delegates to z3-translate defined in z3.sx.
    """
-    from shared.sx.evaluator import _trampoline, _call_lambda
+    from shared.sx.ref.sx_ref import trampoline as _trampoline, call_lambda as _call_lambda

    env = _get_z3_env()
    return _trampoline(_call_lambda(env["z3-translate"], [expr], env))
@@ -72,7 +72,7 @@ def z3_translate_file(source: str) -> str:
    Delegates to z3-translate-file defined in z3.sx.
    """
    from shared.sx.parser import parse_all
-    from shared.sx.evaluator import _trampoline, _call_lambda
+    from shared.sx.ref.sx_ref import trampoline as _trampoline, call_lambda as _call_lambda

    env = _get_z3_env()
    exprs = parse_all(source)
--- a/shared/sx/ref/render.sx
+++ b/shared/sx/ref/render.sx
@@ -134,12 +134,8 @@
 ;; (test body test body ...).
 (define eval-cond
  (fn (clauses env)
-    (if (and (not (empty? clauses))
-             (= (type-of (first clauses)) "list")
-             (= (len (first clauses)) 2))
-      ;; Scheme-style
+    (if (cond-scheme? clauses)
      (eval-cond-scheme clauses env)
-      ;; Clojure-style
      (eval-cond-clojure clauses env))))

 (define eval-cond-scheme
@@ -178,7 +174,9 @@
 ;; bindings = ((name1 expr1) (name2 expr2) ...)
 (define process-bindings
  (fn (bindings env)
-    (let ((local (merge env)))
+    ;; env-extend (not merge) — Env is not a dict subclass, so merge()
+    ;; returns an empty dict, losing all parent scope bindings.
+    (let ((local (env-extend env)))
      (for-each
        (fn (pair)
          (when (and (= (type-of pair) "list") (>= (len pair) 2))
--- a/shared/sx/ref/run_js_sx.py
+++ b/shared/sx/ref/run_js_sx.py
@@ -49,7 +49,7 @@ def load_js_sx() -> dict:

    exprs = parse_all(source)

-    from shared.sx.evaluator import evaluate, make_env
+    from shared.sx.ref.sx_ref import evaluate, make_env

    env = make_env()
    for expr in exprs:
@@ -74,7 +74,7 @@ def compile_ref_to_js(
        spec_modules: List of spec modules (deps, router, signals). None = auto.
    """
    from datetime import datetime, timezone
-    from shared.sx.evaluator import evaluate
+    from shared.sx.ref.sx_ref import evaluate

    ref_dir = _HERE
    env = load_js_sx()
@@ -103,8 +103,11 @@ def compile_ref_to_js(
    if "boot" in adapter_set:
        spec_mod_set.add("router")
        spec_mod_set.add("deps")
+        if "page-helpers" in SPEC_MODULES:
+            spec_mod_set.add("page-helpers")
    has_deps = "deps" in spec_mod_set
    has_router = "router" in spec_mod_set
+    has_page_helpers = "page-helpers" in spec_mod_set

    # Resolve extensions
    ext_set = set()
@@ -198,12 +201,12 @@ def compile_ref_to_js(
        if name in adapter_set and name in adapter_platform:
            parts.append(adapter_platform[name])

-    parts.append(fixups_js(has_html, has_sx, has_dom, has_signals, has_deps))
+    parts.append(fixups_js(has_html, has_sx, has_dom, has_signals, has_deps, has_page_helpers))
    if has_continuations:
        parts.append(CONTINUATIONS_JS)
    if has_dom:
        parts.append(ASYNC_IO_JS)
-    parts.append(public_api_js(has_html, has_sx, has_dom, has_engine, has_orch, has_boot, has_parser, adapter_label, has_deps, has_router, has_signals))
+    parts.append(public_api_js(has_html, has_sx, has_dom, has_engine, has_orch, has_boot, has_parser, adapter_label, has_deps, has_router, has_signals, has_page_helpers))
    parts.append(EPILOGUE)

    build_ts = datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
--- a/shared/sx/ref/run_py_sx.py
+++ b/shared/sx/ref/run_py_sx.py
@@ -38,7 +38,7 @@ def load_py_sx(evaluator_env: dict) -> dict:
    exprs = parse_all(source)

    # Import the evaluator
-    from shared.sx.evaluator import evaluate, make_env
+    from shared.sx.ref.sx_ref import evaluate, make_env

    env = make_env()
    for expr in exprs:
@@ -60,7 +60,7 @@ def extract_defines(source: str) -> list[tuple[str, list]]:


 def main():
-    from shared.sx.evaluator import evaluate
+    from shared.sx.ref.sx_ref import evaluate

    # Load py.sx into evaluator
    env = load_py_sx({})
--- a/shared/sx/ref/sx_ref.py
+++ b/shared/sx/ref/sx_ref.py
--- a/shared/sx/ref/test-aser.sx
+++ b/shared/sx/ref/test-aser.sx
@@ -0,0 +1,272 @@
+;; ==========================================================================
+;; test-aser.sx — Tests for the SX wire format (aser) adapter
+;;
+;; Requires: test-framework.sx loaded first.
+;; Modules tested: adapter-sx.sx (aser, aser-call, aser-fragment, aser-special)
+;;
+;; Platform functions required (beyond test framework):
+;;   render-sx   (sx-source)  -> SX wire format string
+;;     Parses the sx-source string, evaluates via aser in a
+;;     fresh env, and returns the resulting SX wire format string.
+;; ==========================================================================
+
+
+;; --------------------------------------------------------------------------
+;; Basic serialization
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-basics"
+  (deftest "number literal passes through"
+    (assert-equal "42"
+      (render-sx "42")))
+
+  (deftest "string literal passes through"
+    ;; aser returns the raw string value; render-sx concatenates it directly
+    (assert-equal "hello"
+      (render-sx "\"hello\"")))
+
+  (deftest "boolean true passes through"
+    (assert-equal "true"
+      (render-sx "true")))
+
+  (deftest "boolean false passes through"
+    (assert-equal "false"
+      (render-sx "false")))
+
+  (deftest "nil produces empty"
+    (assert-equal ""
+      (render-sx "nil"))))
+
+
+;; --------------------------------------------------------------------------
+;; HTML tag serialization
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-tags"
+  (deftest "simple div"
+    (assert-equal "(div \"hello\")"
+      (render-sx "(div \"hello\")")))
+
+  (deftest "nested tags"
+    (assert-equal "(div (span \"hi\"))"
+      (render-sx "(div (span \"hi\"))")))
+
+  (deftest "multiple children"
+    (assert-equal "(div (p \"a\") (p \"b\"))"
+      (render-sx "(div (p \"a\") (p \"b\"))")))
+
+  (deftest "attributes serialize"
+    (assert-equal "(div :class \"foo\" \"bar\")"
+      (render-sx "(div :class \"foo\" \"bar\")")))
+
+  (deftest "multiple attributes"
+    (assert-equal "(a :href \"/home\" :class \"link\" \"Home\")"
+      (render-sx "(a :href \"/home\" :class \"link\" \"Home\")")))
+
+  (deftest "void elements"
+    (assert-equal "(br)"
+      (render-sx "(br)")))
+
+  (deftest "void element with attrs"
+    (assert-equal "(img :src \"pic.jpg\")"
+      (render-sx "(img :src \"pic.jpg\")"))))
+
+
+;; --------------------------------------------------------------------------
+;; Fragment serialization
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-fragments"
+  (deftest "simple fragment"
+    (assert-equal "(<> (p \"a\") (p \"b\"))"
+      (render-sx "(<> (p \"a\") (p \"b\"))")))
+
+  (deftest "empty fragment"
+    (assert-equal ""
+      (render-sx "(<>)")))
+
+  (deftest "single-child fragment"
+    (assert-equal "(<> (div \"x\"))"
+      (render-sx "(<> (div \"x\"))"))))
+
+
+;; --------------------------------------------------------------------------
+;; Control flow in aser mode
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-control-flow"
+  (deftest "if true branch"
+    (assert-equal "(p \"yes\")"
+      (render-sx "(if true (p \"yes\") (p \"no\"))")))
+
+  (deftest "if false branch"
+    (assert-equal "(p \"no\")"
+      (render-sx "(if false (p \"yes\") (p \"no\"))")))
+
+  (deftest "when true"
+    (assert-equal "(p \"ok\")"
+      (render-sx "(when true (p \"ok\"))")))
+
+  (deftest "when false"
+    (assert-equal ""
+      (render-sx "(when false (p \"ok\"))")))
+
+  (deftest "cond serializes matching branch"
+    (assert-equal "(p \"two\")"
+      (render-sx "(cond false (p \"one\") true (p \"two\") :else (p \"three\"))")))
+
+  (deftest "cond with 2-element predicate test"
+    ;; Regression: cond misclassifies (nil? x) as scheme-style clause.
+    (assert-equal "(p \"yes\")"
+      (render-sx "(cond (nil? nil) (p \"yes\") :else (p \"no\"))"))
+    (assert-equal "(p \"no\")"
+      (render-sx "(cond (nil? \"x\") (p \"yes\") :else (p \"no\"))")))
+
+  (deftest "let binds then serializes"
+    (assert-equal "(p \"hello\")"
+      (render-sx "(let ((x \"hello\")) (p x))")))
+
+  (deftest "let preserves outer scope bindings"
+    ;; Regression: process-bindings must preserve parent env scope chain.
+    ;; Using merge() instead of env-extend loses parent scope items.
+    (assert-equal "(p \"outer\")"
+      (render-sx "(do (define theme \"outer\") (let ((x 1)) (p theme)))")))
+
+  (deftest "nested let preserves outer scope"
+    (assert-equal "(div (span \"hello\") (span \"world\"))"
+      (render-sx "(do (define a \"hello\")
+                      (define b \"world\")
+                      (div (let ((x 1)) (span a))
+                           (let ((y 2)) (span b))))")))
+
+  (deftest "begin serializes last"
+    (assert-equal "(p \"last\")"
+      (render-sx "(begin (p \"first\") (p \"last\"))"))))
+
+
+;; --------------------------------------------------------------------------
+;; THE BUG — map/filter list flattening in children (critical regression)
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-list-flattening"
+  (deftest "map inside tag flattens children"
+    (assert-equal "(div (span \"a\") (span \"b\") (span \"c\"))"
+      (render-sx "(do (define items (list \"a\" \"b\" \"c\"))
+                      (div (map (fn (x) (span x)) items)))")))
+
+  (deftest "map inside tag with other children"
+    (assert-equal "(ul (li \"first\") (li \"a\") (li \"b\"))"
+      (render-sx "(do (define items (list \"a\" \"b\"))
+                      (ul (li \"first\") (map (fn (x) (li x)) items)))")))
+
+  (deftest "filter result via let binding as children"
+    ;; Note: (filter ...) is treated as an SVG tag in aser dispatch (SVG has <filter>),
+    ;; so we evaluate filter via let binding + map to serialize children
+    (assert-equal "(ul (li \"a\") (li \"b\"))"
+      (render-sx "(do (define items (list \"a\" nil \"b\"))
+                      (define kept (filter (fn (x) (not (nil? x))) items))
+                      (ul (map (fn (x) (li x)) kept)))")))
+
+  (deftest "map inside fragment flattens"
+    (assert-equal "(<> (p \"a\") (p \"b\"))"
+      (render-sx "(do (define items (list \"a\" \"b\"))
+                      (<> (map (fn (x) (p x)) items)))")))
+
+  (deftest "nested map does not double-wrap"
+    (assert-equal "(div (span \"1\") (span \"2\"))"
+      (render-sx "(do (define nums (list 1 2))
+                      (div (map (fn (n) (span (str n))) nums)))")))
+
+  (deftest "map with component-like output flattens"
+    (assert-equal "(div (li \"x\") (li \"y\"))"
+      (render-sx "(do (define items (list \"x\" \"y\"))
+                      (div (map (fn (x) (li x)) items)))"))))
+
+
+;; --------------------------------------------------------------------------
+;; Component serialization (NOT expanded in basic aser mode)
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-components"
+  (deftest "unknown component serializes as-is"
+    (assert-equal "(~foo :title \"bar\")"
+      (render-sx "(~foo :title \"bar\")")))
+
+  (deftest "defcomp then unexpanded component call"
+    (assert-equal "(~card :title \"Hi\")"
+      (render-sx "(do (defcomp ~card (&key title) (h1 title)) (~card :title \"Hi\"))")))
+
+  (deftest "component with children serializes unexpanded"
+    (assert-equal "(~box (p \"inside\"))"
+      (render-sx "(do (defcomp ~box (&key &rest children) (div children))
+                      (~box (p \"inside\")))"))))
+
+
+;; --------------------------------------------------------------------------
+;; Definition forms in aser mode
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-definitions"
+  (deftest "define evaluates for side effects, returns nil"
+    (assert-equal "(p 42)"
+      (render-sx "(do (define x 42) (p x))")))
+
+  (deftest "defcomp evaluates and returns nil"
+    (assert-equal "(~tag :x 1)"
+      (render-sx "(do (defcomp ~tag (&key x) (span x)) (~tag :x 1))")))
+
+  (deftest "defisland evaluates AND serializes"
+    (let ((result (render-sx "(defisland ~counter (&key count) (span count))")))
+      (assert-true (string-contains? result "defisland")))))
+
+
+;; --------------------------------------------------------------------------
+;; Function calls in aser mode
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-function-calls"
+  (deftest "named function call evaluates fully"
+    (assert-equal "3"
+      (render-sx "(do (define inc1 (fn (x) (+ x 1))) (inc1 2))")))
+
+  (deftest "define + call"
+    (assert-equal "10"
+      (render-sx "(do (define double (fn (x) (* x 2))) (double 5))")))
+
+  (deftest "native callable with multiple args"
+    ;; Regression: async-aser-eval-call passed evaled-args list to
+    ;; async-invoke (&rest), wrapping it in another list. apply(f, [list])
+    ;; calls f(list) instead of f(*list).
+    (assert-equal "3"
+      (render-sx "(do (define my-add +) (my-add 1 2))")))
+
+  (deftest "native callable with two args via alias"
+    (assert-equal "hello world"
+      (render-sx "(do (define my-join str) (my-join \"hello\" \" world\"))")))
+
+  (deftest "higher-order: map returns list"
+    (let ((result (render-sx "(map (fn (x) (+ x 1)) (list 1 2 3))")))
+      ;; map at top level returns a list, not serialized tags
+      (assert-true (not (nil? result))))))
+
+
+;; --------------------------------------------------------------------------
+;; and/or short-circuit in aser mode
+;; --------------------------------------------------------------------------
+
+(defsuite "aser-logic"
+  (deftest "and short-circuits on false"
+    (assert-equal "false"
+      (render-sx "(and true false true)")))
+
+  (deftest "and returns last truthy"
+    (assert-equal "3"
+      (render-sx "(and 1 2 3)")))
+
+  (deftest "or short-circuits on true"
+    (assert-equal "1"
+      (render-sx "(or 1 2 3)")))
+
+  (deftest "or returns last falsy"
+    (assert-equal "false"
+      (render-sx "(or false false)"))))
--- a/shared/sx/ref/test-eval.sx
+++ b/shared/sx/ref/test-eval.sx
@@ -277,6 +277,29 @@
                        false "b"
                        :else "c")))

+  (deftest "cond with 2-element predicate as first test"
+    ;; Regression: cond misclassifies Clojure-style as scheme-style when
+    ;; the first test is a 2-element list like (nil? x) or (empty? x).
+    ;; The evaluator checks: is first arg a 2-element list? If yes, treats
+    ;; as scheme-style ((test body) ...) — returning the arg instead of
+    ;; evaluating the predicate call.
+    (assert-equal 0 (cond (nil? nil) 0 :else 1))
+    (assert-equal 1 (cond (nil? "x") 0 :else 1))
+    (assert-equal "empty" (cond (empty? (list)) "empty" :else "not-empty"))
+    (assert-equal "not-empty" (cond (empty? (list 1)) "empty" :else "not-empty"))
+    (assert-equal "yes" (cond (not false) "yes" :else "no"))
+    (assert-equal "no" (cond (not true) "yes" :else "no")))
+
+  (deftest "cond with 2-element predicate and no :else"
+    ;; Same bug, but without :else — this is the worst case because the
+    ;; bootstrapper heuristic also breaks (all clauses are 2-element lists).
+    (assert-equal "found"
+      (cond (nil? nil) "found"
+            (nil? "x") "other"))
+    (assert-equal "b"
+      (cond (nil? "x") "a"
+            (not false) "b")))
+
  (deftest "and"
    (assert-true (and true true))
    (assert-false (and true false))
--- a/shared/sx/ref/test-render.sx
+++ b/shared/sx/ref/test-render.sx
@@ -149,7 +149,27 @@

  (deftest "let in render context"
    (assert-equal "<p>hello</p>"
-      (render-html "(let ((x \"hello\")) (p x))"))))
+      (render-html "(let ((x \"hello\")) (p x))")))
+
+  (deftest "cond with 2-element predicate test"
+    ;; Regression: cond misclassifies (nil? x) as scheme-style clause.
+    (assert-equal "<p>yes</p>"
+      (render-html "(cond (nil? nil) (p \"yes\") :else (p \"no\"))"))
+    (assert-equal "<p>no</p>"
+      (render-html "(cond (nil? \"x\") (p \"yes\") :else (p \"no\"))")))
+
+  (deftest "let preserves outer scope bindings"
+    ;; Regression: process-bindings must preserve parent env scope chain.
+    ;; Using merge() on Env objects returns empty dict (Env is not dict subclass).
+    (assert-equal "<p>outer</p>"
+      (render-html "(do (define theme \"outer\") (let ((x 1)) (p theme)))")))
+
+  (deftest "nested let preserves outer scope"
+    (assert-equal "<div><span>hello</span><span>world</span></div>"
+      (render-html "(do (define a \"hello\")
+                        (define b \"world\")
+                        (div (let ((x 1)) (span a))
+                             (let ((y 2)) (span b))))"))))


 ;; --------------------------------------------------------------------------
@@ -165,3 +185,46 @@
    (let ((html (render-html "(do (defcomp ~box (&key &rest children) (div :class \"box\" children)) (~box (p \"inside\")))")))
      (assert-true (string-contains? html "class=\"box\""))
      (assert-true (string-contains? html "<p>inside</p>")))))
+
+
+;; --------------------------------------------------------------------------
+;; Map/filter producing multiple children (aser-adjacent regression tests)
+;; --------------------------------------------------------------------------
+
+(defsuite "render-map-children"
+  (deftest "map producing multiple children inside tag"
+    (assert-equal "<ul><li>a</li><li>b</li><li>c</li></ul>"
+      (render-html "(do (define items (list \"a\" \"b\" \"c\"))
+                        (ul (map (fn (x) (li x)) items)))")))
+
+  (deftest "map with other siblings"
+    (assert-equal "<ul><li>first</li><li>a</li><li>b</li></ul>"
+      (render-html "(do (define items (list \"a\" \"b\"))
+                        (ul (li \"first\") (map (fn (x) (li x)) items)))")))
+
+  (deftest "filter with nil results inside tag"
+    (assert-equal "<ul><li>a</li><li>c</li></ul>"
+      (render-html "(do (define items (list \"a\" nil \"c\"))
+                        (ul (map (fn (x) (li x))
+                                 (filter (fn (x) (not (nil? x))) items))))")))
+
+  (deftest "nested map inside let"
+    (assert-equal "<div><span>1</span><span>2</span></div>"
+      (render-html "(let ((nums (list 1 2)))
+                      (div (map (fn (n) (span n)) nums)))")))
+
+  (deftest "component with &rest receiving mapped results"
+    (let ((html (render-html "(do (defcomp ~list-box (&key &rest children) (div :class \"lb\" children))
+                                  (define items (list \"x\" \"y\"))
+                                  (~list-box (map (fn (x) (p x)) items)))")))
+      (assert-true (string-contains? html "class=\"lb\""))
+      (assert-true (string-contains? html "<p>x</p>"))
+      (assert-true (string-contains? html "<p>y</p>"))))
+
+  (deftest "map-indexed renders with index"
+    (assert-equal "<li>0: a</li><li>1: b</li>"
+      (render-html "(map-indexed (fn (i x) (li (str i \": \" x))) (list \"a\" \"b\"))")))
+
+  (deftest "for-each renders each item"
+    (assert-equal "<p>1</p><p>2</p>"
+      (render-html "(for-each (fn (x) (p x)) (list 1 2))"))))
--- a/shared/sx/resolver.py
+++ b/shared/sx/resolver.py
@@ -31,7 +31,7 @@ import asyncio
 from typing import Any

 from .types import Component, Keyword, Lambda, NIL, Symbol
-from .evaluator import _eval as _raw_eval, _trampoline
+from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline

 def _eval(expr, env):
    """Evaluate and unwrap thunks — all resolver.py _eval calls are non-tail."""
--- a/shared/sx/tests/run.py
+++ b/shared/sx/tests/run.py
@@ -20,7 +20,7 @@ _PROJECT = os.path.abspath(os.path.join(_HERE, "..", "..", ".."))
 sys.path.insert(0, _PROJECT)

 from shared.sx.parser import parse_all
-from shared.sx.evaluator import _eval, _trampoline, _call_lambda
+from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline, call_lambda as _call_lambda
 from shared.sx.types import Symbol, Keyword, Lambda, NIL, Component, Island

 # --- Test state ---
@@ -127,13 +127,38 @@ def render_html(sx_source):
    except ImportError:
        raise RuntimeError("render-to-html not available — sx_ref.py not built")
    exprs = parse_all(sx_source)
-    render_env = dict(env)
+    # Use Env (not flat dict) so tests exercise the real scope chain path.
+    render_env = _Env(dict(env))
    result = ""
    for expr in exprs:
        result += _render_to_html(expr, render_env)
    return result


+# --- Render SX (aser) platform function ---
+
+def render_sx(sx_source):
+    """Parse SX source and serialize to SX wire format via the bootstrapped evaluator."""
+    try:
+        from shared.sx.ref.sx_ref import aser as _aser, serialize as _serialize
+    except ImportError:
+        raise RuntimeError("aser not available — sx_ref.py not built")
+    exprs = parse_all(sx_source)
+    # Use Env (not flat dict) so tests exercise the real scope chain path.
+    # Using dict(env) hides bugs where merge() drops Env parent scopes.
+    render_env = _Env(dict(env))
+    result = ""
+    for expr in exprs:
+        val = _aser(expr, render_env)
+        if isinstance(val, str):
+            result += val
+        elif val is None or val is NIL:
+            pass
+        else:
+            result += _serialize(val)
+    return result
+
+
 # --- Signal platform primitives ---
 # Implements the signal runtime platform interface for testing signals.sx

@@ -258,6 +283,7 @@ SPECS = {
    "parser":        {"file": "test-parser.sx",        "needs": ["sx-parse"]},
    "router":        {"file": "test-router.sx",        "needs": []},
    "render":        {"file": "test-render.sx",        "needs": ["render-html"]},
+    "aser":          {"file": "test-aser.sx",          "needs": ["render-sx"]},
    "deps":          {"file": "test-deps.sx",          "needs": []},
    "engine":        {"file": "test-engine.sx",        "needs": []},
    "orchestration": {"file": "test-orchestration.sx", "needs": []},
@@ -297,8 +323,9 @@ env = _Env({
    "make-keyword": make_keyword,
    "symbol-name": symbol_name,
    "keyword-name": keyword_name,
-    # Render platform function
+    # Render platform functions
    "render-html": render_html,
+    "render-sx": render_sx,
    # Extra primitives needed by spec modules (router.sx, deps.sx)
    "for-each-indexed": "_deferred",  # replaced below
    "dict-set!": "_deferred",
@@ -848,9 +875,9 @@ def main():
            print(f"# --- {spec_name} ---")
            eval_file(spec["file"], env)

-            # Reset render state after render tests to avoid leaking
+            # Reset render state after render/aser tests to avoid leaking
            # into subsequent specs (bootstrapped evaluator checks render_active)
-            if spec_name == "render":
+            if spec_name in ("render", "aser"):
                try:
                    from shared.sx.ref.sx_ref import set_render_active_b
                    set_render_active_b(False)
--- a/shared/sx/tests/test_bootstrapper.py
+++ b/shared/sx/tests/test_bootstrapper.py
@@ -21,7 +21,7 @@ class TestJsSxTranslation:

    def _translate(self, sx_source: str) -> str:
        """Translate a single SX expression to JS using js.sx."""
-        from shared.sx.evaluator import evaluate
+        from shared.sx.ref.sx_ref import evaluate
        env = load_js_sx()
        expr = parse(sx_source)
        env["_def_expr"] = expr
--- a/shared/sx/tests/test_deps.py
+++ b/shared/sx/tests/test_deps.py
@@ -18,7 +18,7 @@ from shared.sx.deps import (

 def make_env(*sx_sources: str) -> dict:
    """Parse and evaluate component definitions into an env dict."""
-    from shared.sx.evaluator import _eval, _trampoline
+    from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline
    env: dict = {}
    for source in sx_sources:
        exprs = parse_all(source)
--- a/shared/sx/tests/test_io_detection.py
+++ b/shared/sx/tests/test_io_detection.py
@@ -23,7 +23,7 @@ from shared.sx.deps import (

 def make_env(*sx_sources: str) -> dict:
    """Parse and evaluate component definitions into an env dict."""
-    from shared.sx.evaluator import _eval, _trampoline
+    from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline
    env: dict = {}
    for source in sx_sources:
        exprs = parse_all(source)
--- a/shared/sx/tests/test_io_proxy.py
+++ b/shared/sx/tests/test_io_proxy.py
@@ -20,7 +20,7 @@ from shared.sx.deps import (

 def make_env(*sx_sources: str) -> dict:
    """Parse and evaluate component definitions into an env dict."""
-    from shared.sx.evaluator import _eval, _trampoline
+    from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline
    env: dict = {}
    for source in sx_sources:
        exprs = parse_all(source)
@@ -282,7 +282,7 @@ class TestIoRoutingLogic:
    """

    def _eval(self, src, env):
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline
        result = None
        for expr in parse_all(src):
            result = _trampoline(_eval(expr, env))
--- a/shared/sx/tests/test_page_data.py
+++ b/shared/sx/tests/test_page_data.py
@@ -156,7 +156,7 @@ class TestDataPageDeps:
    def test_deps_computed_for_data_page(self):
        from shared.sx.deps import components_needed
        from shared.sx.parser import parse_all as pa
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline

        # Define a component
        env = {}
@@ -172,7 +172,7 @@ class TestDataPageDeps:
    def test_deps_transitive_for_data_page(self):
        from shared.sx.deps import components_needed
        from shared.sx.parser import parse_all as pa
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline

        env = {}
        source = """
@@ -205,7 +205,7 @@ class TestDataPipelineSimulation:

    def test_full_pipeline(self):
        from shared.sx.parser import parse_all as pa
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline

        # 1. Define a component that uses only pure primitives
        env = {}
@@ -236,7 +236,7 @@ class TestDataPipelineSimulation:

    def test_pipeline_with_list_data(self):
        from shared.sx.parser import parse_all as pa
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline

        env = {}
        for expr in pa('''
@@ -262,7 +262,7 @@ class TestDataPipelineSimulation:
    def test_pipeline_data_isolation(self):
        """Different data for the same content produces different results."""
        from shared.sx.parser import parse_all as pa
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline

        env = {}
        for expr in pa('(defcomp ~page (&key title count) (str title ": " count))'):
@@ -298,7 +298,7 @@ class TestDataCache:
    def _make_env(self, current_time_ms=1000):
        """Create an env with cache functions and a controllable now-ms."""
        from shared.sx.parser import parse_all as pa
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline

        env = {}
        # Mock now-ms as a callable that returns current_time_ms
@@ -344,7 +344,7 @@ class TestDataCache:

    def _eval(self, src, env):
        from shared.sx.parser import parse_all as pa
-        from shared.sx.evaluator import _eval, _trampoline
+        from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline
        result = None
        for expr in pa(src):
            result = _trampoline(_eval(expr, env))
--- a/shared/sx/tests/test_parity.py
+++ b/shared/sx/tests/test_parity.py
@@ -18,7 +18,7 @@ from shared.sx.types import Symbol, Keyword, Lambda, Component, Macro, NIL

 def hw_eval(text, env=None):
    """Evaluate via hand-written evaluator.py."""
-    from shared.sx.evaluator import evaluate as _evaluate, EvalError
+    from shared.sx.ref.sx_ref import evaluate as _evaluate
    if env is None:
        env = {}
    return _evaluate(parse(text), env)
@@ -50,7 +50,7 @@ def ref_render(text, env=None):

 def hw_eval_multi(text, env=None):
    """Evaluate multiple expressions (e.g. defines then call)."""
-    from shared.sx.evaluator import evaluate as _evaluate
+    from shared.sx.ref.sx_ref import evaluate as _evaluate
    if env is None:
        env = {}
    result = None
@@ -736,7 +736,7 @@ class TestParityDeps:

 class TestParityErrors:
    def test_undefined_symbol(self):
-        from shared.sx.evaluator import EvalError as HwError
+        from shared.sx.types import EvalError as HwError
        from shared.sx.ref.sx_ref import EvalError as RefError
        with pytest.raises(HwError):
            hw_eval("undefined_var")
--- a/shared/sx/tests/test_sx_js.py
+++ b/shared/sx/tests/test_sx_js.py
@@ -12,7 +12,7 @@ import pytest

 from shared.sx.parser import parse, parse_all
 from shared.sx.html import render as py_render
-from shared.sx.evaluator import evaluate
+from shared.sx.ref.sx_ref import evaluate

 SX_JS = Path(__file__).resolve().parents[2] / "static" / "scripts" / "sx.js"
 SX_TEST_JS = Path(__file__).resolve().parents[2] / "static" / "scripts" / "sx-test.js"
--- a/shared/sx/tests/test_sx_spec.py
+++ b/shared/sx/tests/test_sx_spec.py
@@ -7,7 +7,7 @@ from __future__ import annotations

 import pytest
 from shared.sx.parser import parse_all
-from shared.sx.evaluator import _eval, _trampoline
+from shared.sx.ref.sx_ref import eval_expr as _eval, trampoline as _trampoline


 _PREAMBLE = '''(define assert-equal (fn (expected actual) (assert (equal? expected actual) (str "Expected " (str expected) " but got " (str actual)))))
--- a/shared/sx/types.py
+++ b/shared/sx/types.py
@@ -376,6 +376,15 @@ class _ShiftSignal(BaseException):
        self.env = env


+# ---------------------------------------------------------------------------
+# EvalError
+# ---------------------------------------------------------------------------
+
+class EvalError(Exception):
+    """Error during expression evaluation."""
+    pass
+
+
 # ---------------------------------------------------------------------------
 # Type alias
 # ---------------------------------------------------------------------------