diff --git a/sx/sx/specs-explorer.sx b/sx/sx/specs-explorer.sx
index a1214a5..4951c72 100644
--- a/sx/sx/specs-explorer.sx
+++ b/sx/sx/specs-explorer.sx
@@ -64,6 +64,9 @@
     (when (> (get stats "render-count") 0)
       (span :class "bg-sky-100 text-sky-700 px-2 py-0.5 rounded"
         (str (get stats "render-count") " render")))
+    (when (> (get stats "test-total") 0)
+      (span :class "bg-violet-100 text-violet-700 px-2 py-0.5 rounded"
+        (str (get stats "test-total") " tests")))
     (span :class "bg-stone-100 text-stone-500 px-2 py-0.5 rounded"
       (str (get stats "lines") " lines"))))
 
@@ -85,7 +88,7 @@
 
 
 ;; ---------------------------------------------------------------------------
-;; Define card — one function/constant
+;; Define card — one function/constant with all five rings
 ;; ---------------------------------------------------------------------------
 
 (defcomp ~spec-explorer-define (&key d)
@@ -105,10 +108,22 @@
     (when (not (empty? (get d "params")))
       (~spec-param-list :params (get d "params")))
 
-    ;; Translation panels
+    ;; Ring 2: Translation panels (SX + Python + JavaScript + Z3)
     (~spec-ring-translations
       :source (get d "source")
-      :python (get d "python"))))
+      :python (get d "python")
+      :javascript (get d "javascript")
+      :z3 (get d "z3"))
+
+    ;; Ring 3: Cross-references
+    (when (not (empty? (get d "refs")))
+      (~spec-ring-bridge :refs (get d "refs")))
+
+    ;; Ring 4: Tests
+    (when (> (get d "test-count") 0)
+      (~spec-ring-runtime
+        :tests (get d "tests")
+        :test-count (get d "test-count")))))
 
 
 ;; ---------------------------------------------------------------------------
@@ -146,29 +161,76 @@
 
 
 ;; ---------------------------------------------------------------------------
-;; Translation panels (Ring 2)
+;; Ring 2: Translation panels (nucleus + bootstrapper)
 ;; ---------------------------------------------------------------------------
 
-(defcomp ~spec-ring-translations (&key source python)
+(defcomp ~spec-ring-translations (&key source python javascript z3)
   (when (not (= source ""))
     (div :class "mt-3 border border-stone-200 rounded-lg overflow-hidden"
-      ;; SX source — always open
+      ;; SX source — Ring 1: the nucleus (always open)
       (details :open "true"
         (summary :class "px-3 py-1.5 bg-stone-50 text-xs font-medium text-stone-600 cursor-pointer"
           "SX")
         (pre :class "text-xs p-3 overflow-x-auto bg-white"
           (code (highlight source "sx"))))
-      ;; Python
+      ;; Python — Ring 2: bootstrapper
       (when python
         (details
           (summary :class "px-3 py-1.5 bg-stone-50 text-xs font-medium text-stone-600 cursor-pointer border-t border-stone-200"
             "Python")
           (pre :class "text-xs p-3 overflow-x-auto bg-white"
-            (code (highlight python "python"))))))))
+            (code (highlight python "python")))))
+      ;; JavaScript — Ring 2: bootstrapper
+      (when javascript
+        (details
+          (summary :class "px-3 py-1.5 bg-stone-50 text-xs font-medium text-stone-600 cursor-pointer border-t border-stone-200"
+            "JavaScript")
+          (pre :class "text-xs p-3 overflow-x-auto bg-white"
+            (code (highlight javascript "javascript")))))
+      ;; Z3 / SMT-LIB — Ring 2: formal translation
+      (when z3
+        (details
+          (summary :class "px-3 py-1.5 bg-stone-50 text-xs font-medium text-stone-600 cursor-pointer border-t border-stone-200"
+            "Z3 / SMT-LIB")
+          (pre :class "text-xs p-3 overflow-x-auto bg-white"
+            (code (highlight z3 "lisp"))))))))
 
 
 ;; ---------------------------------------------------------------------------
-;; Platform interface table (Ring 3)
+;; Ring 3: Cross-references (bridge)
+;; ---------------------------------------------------------------------------
+
+(defcomp ~spec-ring-bridge (&key refs)
+  (div :class "mt-2"
+    (span :class "text-xs font-medium text-stone-500" "References")
+    (div :class "flex flex-wrap gap-1 mt-1"
+      (map (fn (ref)
+        (a :href (str "#fn-" ref)
+           :class "text-xs px-1.5 py-0.5 rounded bg-stone-100 text-stone-600 font-mono hover:bg-stone-200"
+          ref))
+        refs))))
+
+
+;; ---------------------------------------------------------------------------
+;; Ring 4: Tests (runtime)
+;; ---------------------------------------------------------------------------
+
+(defcomp ~spec-ring-runtime (&key tests test-count)
+  (div :class "mt-2"
+    (div :class "flex items-center gap-1"
+      (span :class "text-xs font-medium text-stone-500" "Tests")
+      (span :class "text-xs px-1.5 py-0.5 rounded bg-violet-100 text-violet-700"
+        (str test-count)))
+    (ul :class "mt-1 text-xs text-stone-500 list-none"
+      (map (fn (t)
+        (li :class "flex items-center gap-1"
+          (span :class "text-green-500 text-xs" "●")
+          (get t "name")))
+        tests))))
+
+
+;; ---------------------------------------------------------------------------
+;; Platform interface table (Ring 3 overview)
 ;; ---------------------------------------------------------------------------
 
 (defcomp ~spec-platform-interface (&key items)
diff --git a/sx/sxc/pages/helpers.py b/sx/sxc/pages/helpers.py
index 431c6ac..b183ff3 100644
--- a/sx/sxc/pages/helpers.py
+++ b/sx/sxc/pages/helpers.py
@@ -172,6 +172,163 @@ def _read_spec_file(filename: str) -> str:
         return ";; spec file not found"
 
 
+# ---------------------------------------------------------------------------
+# Spec explorer — translation + cross-reference helpers
+# ---------------------------------------------------------------------------
+
+_JS_SX_ENV = None  # cached js.sx evaluator env
+
+def _js_translate_define(expr: list, name: str) -> str | None:
+    """Translate a single define expression to JavaScript via js.sx."""
+    global _JS_SX_ENV
+    if _JS_SX_ENV is None:
+        from shared.sx.ref.run_js_sx import load_js_sx
+        _JS_SX_ENV = load_js_sx()
+    from shared.sx.ref.sx_ref import evaluate
+    from shared.sx.types import Symbol
+    env = dict(_JS_SX_ENV)
+    env["_defines"] = [[name, expr]]
+    result = evaluate([Symbol("js-translate-file"), Symbol("_defines")], env)
+    if result and isinstance(result, str) and result.strip():
+        return result.strip()
+    return None
+
+
+def _z3_translate_define(expr: list) -> str | None:
+    """Translate a single define expression to SMT-LIB via z3.sx."""
+    from shared.sx.ref.reader_z3 import z3_translate
+    result = z3_translate(expr)
+    if result and isinstance(result, str) and result.strip():
+        return result.strip()
+    return None
+
+
+_SPEC_INDEX: dict[str, str] | None = None  # function name → spec slug
+
+def _build_spec_index() -> dict[str, str]:
+    """Build a global index mapping function names to spec file slugs."""
+    global _SPEC_INDEX
+    if _SPEC_INDEX is not None:
+        return _SPEC_INDEX
+
+    import os
+    import glob as globmod
+    from shared.sx.parser import parse_all
+    from shared.sx.types import Symbol, Keyword
+
+    ref_dir = os.path.join(os.path.dirname(__file__), "..", "..", "shared", "sx", "ref")
+    if not os.path.isdir(ref_dir):
+        ref_dir = "/app/shared/sx/ref"
+
+    index: dict[str, str] = {}
+    for fp in globmod.glob(os.path.join(ref_dir, "*.sx")):
+        basename = os.path.basename(fp)
+        if basename.startswith("test-"):
+            continue
+        slug = basename.replace(".sx", "")
+        try:
+            with open(fp, encoding="utf-8") as f:
+                content = f.read()
+            for expr in parse_all(content):
+                if not isinstance(expr, list) or len(expr) < 2:
+                    continue
+                if not isinstance(expr[0], Symbol):
+                    continue
+                head = expr[0].name
+                if head in ("define", "define-async"):
+                    name = expr[1].name if isinstance(expr[1], Symbol) else str(expr[1])
+                    index[name] = slug
+        except Exception:
+            continue
+
+    _SPEC_INDEX = index
+    return _SPEC_INDEX
+
+
+# Test file → spec file mapping
+_SPEC_TO_TEST = {
+    "signals.sx": "test-signals.sx",
+    "eval.sx": "test-eval.sx",
+    "parser.sx": "test-parser.sx",
+    "render.sx": "test-render.sx",
+    "engine.sx": "test-engine.sx",
+    "orchestration.sx": "test-orchestration.sx",
+    "router.sx": "test-router.sx",
+    "deps.sx": "test-deps.sx",
+    "adapter-sx.sx": "test-aser.sx",
+    "types.sx": "test-types.sx",
+}
+
+
+def _extract_tests_for_spec(filename: str) -> list[dict]:
+    """Extract test suites/cases from the corresponding test file."""
+    import os
+    from shared.sx.parser import parse_all
+    from shared.sx.types import Symbol
+
+    test_file = _SPEC_TO_TEST.get(filename)
+    if not test_file:
+        return []
+
+    ref_dir = os.path.join(os.path.dirname(__file__), "..", "..", "shared", "sx", "ref")
+    if not os.path.isdir(ref_dir):
+        ref_dir = "/app/shared/sx/ref"
+    test_path = os.path.join(ref_dir, test_file)
+
+    try:
+        with open(test_path, encoding="utf-8") as f:
+            content = f.read()
+        exprs = parse_all(content)
+    except Exception:
+        return []
+
+    tests: list[dict] = []
+    for expr in exprs:
+        if not isinstance(expr, list) or len(expr) < 3:
+            continue
+        if not isinstance(expr[0], Symbol):
+            continue
+        if expr[0].name != "defsuite":
+            continue
+        suite_name = expr[1] if isinstance(expr[1], str) else str(expr[1])
+        test_names = []
+        for child in expr[2:]:
+            if isinstance(child, list) and len(child) >= 2:
+                if isinstance(child[0], Symbol) and child[0].name == "deftest":
+                    tname = child[1] if isinstance(child[1], str) else str(child[1])
+                    test_names.append(tname)
+        tests.append({"suite": suite_name, "tests": test_names})
+    return tests
+
+
+def _match_tests_to_function(fn_name: str, all_tests: list[dict]) -> list[dict]:
+    """Match test suites to a function by fuzzy name matching."""
+    matched = []
+    fn_lower = fn_name.lower().replace("-", " ").replace("!", "").replace("?", "")
+    fn_words = set(fn_lower.split())
+    for suite in all_tests:
+        suite_lower = suite["suite"].lower()
+        # Match if function name appears in suite name or suite name contains function
+        if fn_lower in suite_lower or any(w in suite_lower for w in fn_words if len(w) > 2):
+            matched.append(suite)
+    return matched
+
+
+def _collect_symbols(expr) -> set[str]:
+    """Recursively collect all Symbol names referenced in an expression."""
+    from shared.sx.types import Symbol
+    result: set[str] = set()
+    if isinstance(expr, Symbol):
+        result.add(expr.name)
+    elif isinstance(expr, list):
+        for item in expr:
+            result |= _collect_symbols(item)
+    elif isinstance(expr, dict):
+        for v in expr.values():
+            result |= _collect_symbols(v)
+    return result
+
+
 def _spec_explorer_data(filename: str, title: str = "", desc: str = "") -> dict | None:
     """Parse a spec file into structured metadata for the spec explorer.
 
@@ -369,6 +526,34 @@ def _spec_explorer_data(filename: str, title: str = "", desc: str = "") -> dict
         except Exception:
             pass
 
+        # --- JavaScript translation ---
+        js_code = None
+        try:
+            js_code = _js_translate_define(expr, name)
+        except Exception:
+            pass
+
+        # --- Z3/SMT-LIB translation ---
+        z3_code = None
+        try:
+            z3_code = _z3_translate_define(expr)
+        except Exception:
+            pass
+
+        # --- Cross-references ---
+        refs = []
+        platform_deps = []
+        try:
+            spec_index = _build_spec_index()
+            body_symbols = _collect_symbols(expr)
+            own_names = {name}
+            for sym in body_symbols - own_names:
+                if sym in spec_index:
+                    refs.append(sym)
+                # Symbols not in any spec file might be platform primitives
+        except Exception:
+            pass
+
         define_entry = {
             "name": name,
             "kind": kind,
@@ -377,6 +562,11 @@ def _spec_explorer_data(filename: str, title: str = "", desc: str = "") -> dict
             "source": src,
             "line": line_num,
             "python": py_code,
+            "javascript": js_code,
+            "z3": z3_code,
+            "refs": refs,
+            "tests": [],
+            "test-count": 0,
         }
         all_defines.append(define_entry)
 
@@ -401,6 +591,20 @@ def _spec_explorer_data(filename: str, title: str = "", desc: str = "") -> dict
                 target_section = s
         target_section["defines"].append(d)
 
+    # --- Test matching ---
+    all_tests = _extract_tests_for_spec(filename)
+    test_total = 0
+    for d in all_defines:
+        matched = _match_tests_to_function(d["name"], all_tests)
+        if matched:
+            test_names = []
+            for suite in matched:
+                for t in suite["tests"]:
+                    test_names.append({"name": t, "suite": suite["suite"]})
+            d["tests"] = test_names
+            d["test-count"] = len(test_names)
+            test_total += len(test_names)
+
     # --- Stats ---
     pure_count = sum(1 for d in all_defines if not d["effects"])
     mutation_count = sum(1 for d in all_defines if "mutation" in d["effects"])
@@ -435,6 +639,7 @@ def _spec_explorer_data(filename: str, title: str = "", desc: str = "") -> dict
             "io-count": io_count,
             "render-count": render_count,
             "lines": len(lines),
+            "test-total": test_total,
         },
     }