diff --git a/host/chez/converters.ss b/host/chez/converters.ss
index b5405ac..f0726d9 100644
--- a/host/chez/converters.ss
+++ b/host/chez/converters.ss
@@ -27,6 +27,15 @@
     ((and (flonum? v) (fl= v +inf.0)) "Infinity")
     ((and (flonum? v) (fl= v -inf.0)) "-Infinity")
     ((and (flonum? v) (not (fl= v v))) "NaN")
+    ;; a symbol stringifies to its name (JVM Symbol.toString returns the interned
+    ;; name), so (str sym) of a no-ns symbol is the SAME string object the symbol
+    ;; holds — code that compares those by identity (core.logic's non-unique lvar
+    ;; equality) depends on it.
+    ((symbol-t? v)
+     (let ((ns (symbol-t-ns v)))
+       (if (or (not ns) (jolt-nil? ns))
+           (symbol-t-name v)
+           (string-append ns "/" (symbol-t-name v)))))
     (else
      (let loop ((rs str-render-registry))
        (cond
@@ -49,10 +58,17 @@
       (jolt-pr-readable v)
       (jolt-str-render-one v)))
 (define (jolt-str . xs)
-  (let loop ((xs xs) (acc '()))
-    (if (null? xs)
-        (apply string-append (reverse acc))
-        (loop (cdr xs) (cons (jolt-str-one (car xs)) acc)))))
+  (cond
+    ((null? xs) "")
+    ;; single arg returns its rendering directly (no string-append copy), so
+    ;; (str sym) hands back the symbol's own name string — JVM (str x) is
+    ;; x.toString(), and core.logic's non-unique lvar equality compares those by
+    ;; identity.
+    ((null? (cdr xs)) (jolt-str-one (car xs)))
+    (else (let loop ((xs xs) (acc '()))
+            (if (null? xs)
+                (apply string-append (reverse acc))
+                (loop (cdr xs) (cons (jolt-str-one (car xs)) acc)))))))
 
 ;; jolt indices are flonums; substring etc. need exact ints.
 (define (jolt->idx n) (exact (truncate n)))
diff --git a/host/chez/host-contract.ss b/host/chez/host-contract.ss
index fbbf083..d747902 100644
--- a/host/chez/host-contract.ss
+++ b/host/chez/host-contract.ss
@@ -326,6 +326,10 @@
           ;; Referred names live in a separate table, so this only hits a real
           ;; local intern, matching how the analyzer resolves the bare symbol.
           ((var-cell-lookup (chez-actx-cns ctx) nm) (jolt-symbol (chez-actx-cns ctx) nm))
+          ;; a name the compile ns excluded from clojure.core (:refer-clojure
+          ;; :exclude) is not clojure.core/nm even before the ns defines its own —
+          ;; qualify to the compile ns, like Clojure (core.logic.fd's `==`).
+          ((chez-core-excluded? (chez-actx-cns ctx) nm) (jolt-symbol (chez-actx-cns ctx) nm))
           ((var-cell-lookup "clojure.core" nm) (jolt-symbol "clojure.core" nm))
           ;; a name referred into the compile ns (:require :refer / :use :only)
           ;; qualifies to its SOURCE ns, not the compile ns — so a macro that
diff --git a/host/chez/ns.ss b/host/chez/ns.ss
index 9d39013..cad5286 100644
--- a/host/chez/ns.ss
+++ b/host/chez/ns.ss
@@ -281,7 +281,29 @@
                     (chez-register-refer! cns (var-cell-name c) target)))
       (hashtable-values var-table))
     jolt-nil))
-(define (jolt-refer-clojure . _) jolt-nil)
+;; (:refer-clojure :exclude [names…]) — clojure.core always resolves on Chez, so
+;; the only thing to track is the EXCLUDE set: an excluded name is not
+;; clojure.core/name, so syntax-quote qualifies it to the current ns instead (a ns
+;; that excludes and defines its own, e.g. core.logic.fd's ==).
+(define ns-core-exclude-table (make-hashtable equal-hash equal?))  ; cns -> (name -> #t)
+(define (chez-register-core-exclude! cns name)
+  (let ((h (or (hashtable-ref ns-core-exclude-table cns #f)
+               (let ((h (make-hashtable string-hash string=?)))
+                 (hashtable-set! ns-core-exclude-table cns h) h))))
+    (hashtable-set! h name #t)))
+(define (chez-core-excluded? cns name)
+  (let ((h (hashtable-ref ns-core-exclude-table cns #f)))
+    (and h (hashtable-ref h name #f) #t)))
+(define (jolt-refer-clojure . args)
+  (let ((cns (chez-current-ns)))
+    (let loop ((a args))
+      (when (and (pair? a) (pair? (cdr a)))
+        (when (and (keyword? (car a)) (string=? (keyword-t-name (car a)) "exclude"))
+          (for-each (lambda (n) (when (symbol-t? n)
+                                  (chez-register-core-exclude! cns (symbol-t-name n))))
+                    (seq->list (cadr a))))
+        (loop (cddr a)))))
+  jolt-nil)
 
 ;; alter-meta! / reset-meta!: update a var's metadata (var-meta-table, rt.ss).
 (define (jolt-alter-meta! ref f . args)
diff --git a/host/chez/records.ss b/host/chez/records.ss
index 7aedc74..4f516d3 100644
--- a/host/chez/records.ss
+++ b/host/chez/records.ss
@@ -505,6 +505,21 @@
         ;; a bare procedure (fn) — extend-protocol to clojure.lang.{Fn,IFn,AFn}.
         ((procedure? obj) '("Fn" "IFn" "AFn" "Object"))
         ((jolt-nil? obj) '("nil"))
+        ;; a defrecord IS the clojure.lang map/record interfaces, so a protocol
+        ;; extended to IRecord / IPersistentMap / Associative / Seqable / … (and not
+        ;; to the record's own type) dispatches to it — e.g. core.logic extends
+        ;; IWalkTerm to clojure.lang.IRecord, and walking a record value must hit
+        ;; that, not the Object default (which would recur forever). The record's
+        ;; own type is tried first (dispatch checks jrec-tag before these tags).
+        ((jrec-record? obj)
+         (cons (jrec-tag obj)
+               '("IRecord" "clojure.lang.IRecord" "IPersistentMap" "clojure.lang.IPersistentMap"
+                 "APersistentMap" "Associative" "ILookup" "Seqable" "Counted"
+                 "IPersistentCollection" "IObj" "IMeta" "Map" "java.util.Map"
+                 "Iterable" "java.lang.Iterable" "Object")))
+        ;; a bare deftype is opaque — its declared interfaces dispatch via the
+        ;; inline methods registered under its own tag (tried before these tags).
+        ((jrec? obj) (list (jrec-tag obj) "Object"))
         (else '("Object"))))
 
 (define (record-tag obj) (and (jrec? obj) (jrec-tag obj)))
diff --git a/host/chez/seed/image.ss b/host/chez/seed/image.ss
index 41011b6..3e5f403 100644
--- a/host/chez/seed/image.ss
+++ b/host/chez/seed/image.ss
@@ -119,7 +119,7 @@
 (guard (e (#t #f))
   (def-var-with-meta! "jolt.analyzer" "analyze-symbol" (letrec ((analyze-symbol (lambda (ctx form env) (let fnrec8868 ((ctx ctx) (form form) (env env)) (let* ((nm (jolt-invoke (var-deref "jolt.host" "form-sym-name") form)) (ns (jolt-invoke (var-deref "jolt.host" "form-sym-ns") form))) (if (jolt-truthy? (let* ((and__25__auto (jolt-nil? ns))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "local?") env nm) and__25__auto))) (let* ((h (jolt-get (jolt-get env (keyword #f "hints")) nm))) (if (jolt-truthy? h) (jolt-assoc (jolt-invoke (var-deref "jolt.ir" "local") nm) (keyword #f "hint") h) (jolt-invoke (var-deref "jolt.ir" "local") nm))) (if (jolt-truthy? ns) (let* ((r (jolt-invoke (var-deref "jolt.host" "resolve-global") ctx form))) (if (jolt= (keyword #f "var") (jolt-get r (keyword #f "kind"))) (let* ((G__150 (let* ((_a$8869 (var-deref "jolt.ir" "var-ref")) (_a$8870 (jolt-get r (keyword #f "ns"))) (_a$8871 (jolt-get r (keyword #f "name")))) (jolt-invoke _a$8869 _a$8870 _a$8871)))) (let* ((G__151 (if (jolt-truthy? (jolt-get r (keyword #f "num-ret"))) (jolt-assoc G__150 (keyword #f "num-ret") (jolt-get r (keyword #f "num-ret"))) G__150))) G__151)) (jolt-invoke (var-deref "jolt.ir" "host-static") ns nm))) (if (jolt-truthy? (keyword #f "else")) (let* ((r (jolt-invoke (var-deref "jolt.host" "resolve-global") ctx form))) (let* ((G__152 (jolt-get r (keyword #f "kind")))) (if (jolt= G__152 (keyword #f "var")) (let* ((G__153 (let* ((_a$8872 (var-deref "jolt.ir" "var-ref")) (_a$8873 (jolt-get r (keyword #f "ns"))) (_a$8874 (jolt-get r (keyword #f "name")))) (jolt-invoke _a$8872 _a$8873 _a$8874)))) (let* ((G__154 (if (jolt-truthy? (jolt-get r (keyword #f "num-ret"))) (jolt-assoc G__153 (keyword #f "num-ret") (jolt-get r (keyword #f "num-ret"))) G__153))) G__154)) (if (jolt= G__152 (keyword #f "host")) (jolt-invoke (var-deref "jolt.ir" "host-ref") (jolt-get r (keyword #f "name"))) (if (jolt= G__152 (keyword #f "class")) (jolt-invoke (var-deref "jolt.ir" "const") (jolt-get r (keyword #f "name"))) (if (jolt-truthy? (jolt-invoke (var-deref "jolt.host" "late-bind?") ctx)) (jolt-invoke (var-deref "jolt.ir" "var-ref") (jolt-invoke (var-deref "jolt.host" "compile-ns") ctx) nm) (jolt-invoke (var-deref "jolt.analyzer" "uncompilable") (jolt-invoke (var-deref "clojure.core" "str") "Unable to resolve symbol: " nm " in this context")))))))) jolt-nil)))))))) analyze-symbol) (let* ((_o$8875 (keyword #f "private")) (_o$8876 #t)) (jolt-hash-map _o$8875 _o$8876))))
 (guard (e (#t #f))
-  (def-var-with-meta! "jolt.analyzer" "analyze-list" (letrec ((analyze-list (lambda (ctx form env) (let fnrec8877 ((ctx ctx) (form form) (env env)) (let* ((items (jolt-invoke (var-deref "clojure.core" "vec") (jolt-invoke (var-deref "jolt.host" "form-elements") form)))) (if (jolt-zero? (jolt-count items)) (jolt-invoke (var-deref "jolt.ir" "quote-node") form) (let* ((head (jolt-first items)) (hname (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (jolt-nil? (jolt-invoke (var-deref "jolt.host" "form-sym-ns") head)) and__25__auto))) (jolt-invoke (var-deref "jolt.host" "form-sym-name") head) jolt-nil)) (shadowed (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "local?") env hname) and__25__auto)))) (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not (jolt-contains? (var-deref "jolt.analyzer" "handled") hname)))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.host" "form-macro?") ctx head) and__25__auto)) and__25__auto)) and__25__auto))) (let* ((node (jolt-invoke (var-deref "jolt.analyzer" "analyze") ctx (jolt-invoke (var-deref "jolt.host" "form-expand-1") ctx form) env)) (p (jolt-invoke (var-deref "jolt.host" "form-position") form))) (if (jolt-truthy? (let* ((and__25__auto p)) (if (jolt-truthy? and__25__auto) (jolt= (keyword #f "def") (jolt-get node (keyword #f "op"))) and__25__auto))) (jolt-assoc node (keyword #f "pos") p) node)) (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt= "jolt.ffi" (jolt-invoke (var-deref "jolt.host" "form-sym-ns") head)))) (if (jolt-truthy? and__25__auto) (jolt= "__cfn" (jolt-invoke (var-deref "jolt.host" "form-sym-name") head)) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-ffi-fn") ctx items env) (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt= "jolt.ffi" (jolt-invoke (var-deref "jolt.host" "form-sym-ns") head)))) (if (jolt-truthy? and__25__auto) (jolt= "__ccallable" (jolt-invoke (var-deref "jolt.host" "form-sym-name") head)) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-ffi-callable") ctx items env) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (jolt-contains? (var-deref "jolt.analyzer" "handled") hname) and__25__auto))) (let* ((node (jolt-invoke (var-deref "jolt.analyzer" "analyze-special") ctx hname items env)) (p (jolt-invoke (var-deref "jolt.host" "form-position") form))) (if (jolt-truthy? (let* ((and__25__auto p)) (if (jolt-truthy? and__25__auto) (jolt= (keyword #f "def") (jolt-get node (keyword #f "op"))) and__25__auto))) (jolt-assoc node (keyword #f "pos") p) node)) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "method-head?") hname) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-host-call") ctx hname items env) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "ctor-head?") hname) and__25__auto)) and__25__auto))) (let* ((_a$8878 (var-deref "jolt.analyzer" "analyze-ctor")) (_a$8879 ctx) (_a$8880 (jolt-invoke (var-deref "clojure.core" "subs") hname 0 (jolt-dec (jolt-count hname)))) (_a$8881 (jolt-rest items)) (_a$8882 env)) (jolt-invoke _a$8878 _a$8879 _a$8880 _a$8881 _a$8882)) (if (jolt-truthy? (let* ((and__25__auto (jolt= hname "new"))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (>= (jolt-count items) 2))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.host" "form-sym?") (jolt-nth items 1)) and__25__auto)) and__25__auto)) and__25__auto))) (let* ((_a$8883 (var-deref "jolt.analyzer" "analyze-ctor")) (_a$8884 ctx) (_a$8885 (jolt-invoke (var-deref "jolt.host" "form-sym-name") (jolt-nth items 1))) (_a$8886 (jolt-drop 2 items)) (_a$8887 env)) (jolt-invoke _a$8883 _a$8884 _a$8885 _a$8886 _a$8887)) (if (let* ((and__25__auto (jolt= hname "."))) (if (jolt-truthy? and__25__auto) (jolt-not shadowed) and__25__auto)) (jolt-invoke (var-deref "jolt.analyzer" "analyze-dot") ctx items env) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "field-head?") hname) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-field") ctx hname items env) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.host" "form-special?") hname) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "uncompilable") (jolt-invoke (var-deref "clojure.core" "str") "special form " hname)) (if (jolt-truthy? (keyword #f "else")) (let* ((n (let* ((_a$8892 (var-deref "jolt.ir" "invoke")) (_a$8893 (jolt-invoke (var-deref "jolt.analyzer" "analyze") ctx head env)) (_a$8894 (let* ((_a$8889 (var-deref "clojure.core" "mapv")) (_a$8890 (lambda (p__98_) (let fnrec8888 ((p__98_ p__98_)) (jolt-invoke (var-deref "jolt.analyzer" "analyze") ctx p__98_ env)))) (_a$8891 (jolt-rest items))) (jolt-invoke _a$8889 _a$8890 _a$8891)))) (jolt-invoke _a$8892 _a$8893 _a$8894))) (p (jolt-invoke (var-deref "jolt.host" "form-position") form))) (if (jolt-truthy? p) (jolt-assoc n (keyword #f "pos") p) n)) jolt-nil)))))))))))))))))) analyze-list) (let* ((_o$8895 (keyword #f "private")) (_o$8896 #t)) (jolt-hash-map _o$8895 _o$8896))))
+  (def-var-with-meta! "jolt.analyzer" "analyze-list" (letrec ((analyze-list (lambda (ctx form env) (let fnrec8877 ((ctx ctx) (form form) (env env)) (let* ((items (jolt-invoke (var-deref "clojure.core" "vec") (jolt-invoke (var-deref "jolt.host" "form-elements") form)))) (if (jolt-zero? (jolt-count items)) (jolt-invoke (var-deref "jolt.ir" "quote-node") form) (let* ((head (jolt-first items)) (hname (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (jolt-nil? (jolt-invoke (var-deref "jolt.host" "form-sym-ns") head)) and__25__auto))) (jolt-invoke (var-deref "jolt.host" "form-sym-name") head) jolt-nil)) (sf-name (let* ((or__26__auto hname)) (if (jolt-truthy? or__26__auto) or__26__auto (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt= "clojure.core" (jolt-invoke (var-deref "jolt.host" "form-sym-ns") head)))) (if (jolt-truthy? and__25__auto) (jolt-contains? (var-deref "jolt.analyzer" "handled") (jolt-invoke (var-deref "jolt.host" "form-sym-name") head)) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.host" "form-sym-name") head) jolt-nil)))) (shadowed (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "local?") env hname) and__25__auto)))) (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not (jolt-contains? (var-deref "jolt.analyzer" "handled") sf-name)))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.host" "form-macro?") ctx head) and__25__auto)) and__25__auto)) and__25__auto))) (let* ((node (jolt-invoke (var-deref "jolt.analyzer" "analyze") ctx (jolt-invoke (var-deref "jolt.host" "form-expand-1") ctx form) env)) (p (jolt-invoke (var-deref "jolt.host" "form-position") form))) (if (jolt-truthy? (let* ((and__25__auto p)) (if (jolt-truthy? and__25__auto) (jolt= (keyword #f "def") (jolt-get node (keyword #f "op"))) and__25__auto))) (jolt-assoc node (keyword #f "pos") p) node)) (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt= "jolt.ffi" (jolt-invoke (var-deref "jolt.host" "form-sym-ns") head)))) (if (jolt-truthy? and__25__auto) (jolt= "__cfn" (jolt-invoke (var-deref "jolt.host" "form-sym-name") head)) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-ffi-fn") ctx items env) (if (jolt-truthy? (let* ((and__25__auto (jolt-invoke (var-deref "jolt.host" "form-sym?") head))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt= "jolt.ffi" (jolt-invoke (var-deref "jolt.host" "form-sym-ns") head)))) (if (jolt-truthy? and__25__auto) (jolt= "__ccallable" (jolt-invoke (var-deref "jolt.host" "form-sym-name") head)) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-ffi-callable") ctx items env) (if (jolt-truthy? (let* ((and__25__auto sf-name)) (if (jolt-truthy? and__25__auto) (jolt-contains? (var-deref "jolt.analyzer" "handled") sf-name) and__25__auto))) (let* ((node (jolt-invoke (var-deref "jolt.analyzer" "analyze-special") ctx sf-name items env)) (p (jolt-invoke (var-deref "jolt.host" "form-position") form))) (if (jolt-truthy? (let* ((and__25__auto p)) (if (jolt-truthy? and__25__auto) (jolt= (keyword #f "def") (jolt-get node (keyword #f "op"))) and__25__auto))) (jolt-assoc node (keyword #f "pos") p) node)) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "method-head?") hname) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-host-call") ctx hname items env) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "ctor-head?") hname) and__25__auto)) and__25__auto))) (let* ((_a$8878 (var-deref "jolt.analyzer" "analyze-ctor")) (_a$8879 ctx) (_a$8880 (jolt-invoke (var-deref "clojure.core" "subs") hname 0 (jolt-dec (jolt-count hname)))) (_a$8881 (jolt-rest items)) (_a$8882 env)) (jolt-invoke _a$8878 _a$8879 _a$8880 _a$8881 _a$8882)) (if (jolt-truthy? (let* ((and__25__auto (jolt= hname "new"))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (>= (jolt-count items) 2))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.host" "form-sym?") (jolt-nth items 1)) and__25__auto)) and__25__auto)) and__25__auto))) (let* ((_a$8883 (var-deref "jolt.analyzer" "analyze-ctor")) (_a$8884 ctx) (_a$8885 (jolt-invoke (var-deref "jolt.host" "form-sym-name") (jolt-nth items 1))) (_a$8886 (jolt-drop 2 items)) (_a$8887 env)) (jolt-invoke _a$8883 _a$8884 _a$8885 _a$8886 _a$8887)) (if (let* ((and__25__auto (jolt= hname "."))) (if (jolt-truthy? and__25__auto) (jolt-not shadowed) and__25__auto)) (jolt-invoke (var-deref "jolt.analyzer" "analyze-dot") ctx items env) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.analyzer" "field-head?") hname) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "analyze-field") ctx hname items env) (if (jolt-truthy? (let* ((and__25__auto hname)) (if (jolt-truthy? and__25__auto) (let* ((and__25__auto (jolt-not shadowed))) (if (jolt-truthy? and__25__auto) (jolt-invoke (var-deref "jolt.host" "form-special?") hname) and__25__auto)) and__25__auto))) (jolt-invoke (var-deref "jolt.analyzer" "uncompilable") (jolt-invoke (var-deref "clojure.core" "str") "special form " hname)) (if (jolt-truthy? (keyword #f "else")) (let* ((n (let* ((_a$8892 (var-deref "jolt.ir" "invoke")) (_a$8893 (jolt-invoke (var-deref "jolt.analyzer" "analyze") ctx head env)) (_a$8894 (let* ((_a$8889 (var-deref "clojure.core" "mapv")) (_a$8890 (lambda (p__98_) (let fnrec8888 ((p__98_ p__98_)) (jolt-invoke (var-deref "jolt.analyzer" "analyze") ctx p__98_ env)))) (_a$8891 (jolt-rest items))) (jolt-invoke _a$8889 _a$8890 _a$8891)))) (jolt-invoke _a$8892 _a$8893 _a$8894))) (p (jolt-invoke (var-deref "jolt.host" "form-position") form))) (if (jolt-truthy? p) (jolt-assoc n (keyword #f "pos") p) n)) jolt-nil)))))))))))))))))) analyze-list) (let* ((_o$8895 (keyword #f "private")) (_o$8896 #t)) (jolt-hash-map _o$8895 _o$8896))))
 (guard (e (#t #f))
   (def-var-with-meta! "jolt.analyzer" "with-coll-meta" (letrec ((with-coll-meta (lambda (ctx form env node) (let fnrec8897 ((ctx ctx) (form form) (env env) (node node)) (let* ((m (jolt-invoke (var-deref "jolt.host" "form-coll-meta") form))) (if (jolt-nil? m) node (let* ((_a$8900 (var-deref "jolt.ir" "invoke")) (_a$8901 (jolt-invoke (var-deref "jolt.ir" "var-ref") "clojure.core" "with-meta")) (_a$8902 (let* ((_o$8898 node) (_o$8899 (jolt-invoke (var-deref "jolt.analyzer" "analyze") ctx m env))) (jolt-vector _o$8898 _o$8899)))) (jolt-invoke _a$8900 _a$8901 _a$8902)))))))) with-coll-meta) (let* ((_o$8903 (keyword #f "private")) (_o$8904 #t)) (jolt-hash-map _o$8903 _o$8904))))
 (guard (e (#t #f))
diff --git a/host/chez/transients.ss b/host/chez/transients.ss
index d2023b5..73cba7c 100644
--- a/host/chez/transients.ss
+++ b/host/chez/transients.ss
@@ -171,8 +171,11 @@
 
 ;; persistent disj over sets (pset-disj already exists in collections.ss).
 (define (jolt-disj s . xs)
-  (meta-carry s
-    (let loop ((s s) (xs xs)) (if (null? xs) s (loop (pset-disj s (car xs)) (cdr xs))))))
+  ;; (disj nil ...) is nil on the JVM (disj is otherwise set-only).
+  (if (jolt-nil? s)
+      jolt-nil
+      (meta-carry s
+        (let loop ((s s) (xs xs)) (if (null? xs) s (loop (pset-disj s (car xs)) (cdr xs)))))))
 
 ;; --- see-through accessors ---------------------------------------------------
 (define (tvec-in-bounds? t i) (and (fixnum? i) (fx>=? i 0) (fx<? i (jolt-transient-n t))))
diff --git a/host/chez/values.ss b/host/chez/values.ss
index dd79141..02a694a 100644
--- a/host/chez/values.ss
+++ b/host/chez/values.ss
@@ -47,9 +47,21 @@
 (define (keyword? x) (keyword-t? x))
 
 ;; --- symbols: ns + name + meta; NOT interned (meta varies), = by ns/name ------
+;; The ns/name STRINGS are pooled (like JVM Symbol.intern, which .intern()s them):
+;; two separately-read `?a` symbols share one name-string object, so code that
+;; compares symbol names by identity (core.logic's non-unique lvar equality, via
+;; (str sym)) behaves like the JVM.
+(define symbol-string-pool (make-hashtable string-hash string=?))
+(define (intern-symbol-string s)
+  (if (string? s)
+      (or (hashtable-ref symbol-string-pool s #f)
+          (begin (hashtable-set! symbol-string-pool s s) s))
+      s))
 (define-record-type symbol-t (fields ns name meta) (nongenerative symbol-v1))
-(define (jolt-symbol ns name) (make-symbol-t ns name jolt-nil))
-(define (jolt-symbol/meta ns name meta) (make-symbol-t ns name meta))
+(define (jolt-symbol ns name)
+  (make-symbol-t (intern-symbol-string ns) (intern-symbol-string name) jolt-nil))
+(define (jolt-symbol/meta ns name meta)
+  (make-symbol-t (intern-symbol-string ns) (intern-symbol-string name) meta))
 (define (jolt-symbol? x) (symbol-t? x))
 
 ;; chars/strings: Chez natives (strings treated immutable).
diff --git a/jolt-core/jolt/analyzer.clj b/jolt-core/jolt/analyzer.clj
index 5bb3514..34e6cce 100644
--- a/jolt-core/jolt/analyzer.clj
+++ b/jolt-core/jolt/analyzer.clj
@@ -611,6 +611,15 @@
       (quote-node form)
       (let [head (first items)
             hname (when (and (form-sym? head) (nil? (form-sym-ns head))) (form-sym-name head))
+            ;; a special-form head may arrive clojure.core-qualified: syntax-quote
+            ;; namespace-qualifies a macro like `letfn` to `clojure.core/letfn`
+            ;; (matching Clojure, where it is a macro), so a macro-emitted
+            ;; (clojure.core/letfn …) must still dispatch to the special form.
+            sf-name (or hname
+                        (when (and (form-sym? head)
+                                   (= "clojure.core" (form-sym-ns head))
+                                   (contains? handled (form-sym-name head)))
+                          (form-sym-name head)))
             shadowed (and hname (local? env hname))]
         (cond
           ;; Canonical order (Clojure/CLJS analyze-seq): macroexpand FIRST, then
@@ -619,7 +628,7 @@
           ;; the reference macroexpand1's isSpecial check — so a ns that redefs a
           ;; macro `def`/`and`/`or` (clojure.spec.alpha) keeps the special form `def`.
           (and (form-sym? head) (not shadowed)
-               (not (contains? handled hname)) (form-macro? ctx head))
+               (not (contains? handled sf-name)) (form-macro? ctx head))
             ;; defn/defn- expand to (def name (fn …)); carry the ORIGINAL form's
             ;; source offset onto the resulting def, since the macro builds a fresh
             ;; (def …) with no metadata. So the back end can register fn defs.
@@ -639,10 +648,10 @@
           ;; special-form heads are NOT shadowable (unlike macros): a local named
           ;; `if` does not change the meaning of (if …) in operator position, per
           ;; spec §3 and the reference. No (not shadowed) guard here.
-          (and hname (contains? handled hname))
+          (and sf-name (contains? handled sf-name))
             ;; stamp the form's source offset onto a top-level def so the back end
             ;; can register it (jv$ns$name -> source) for native stack traces.
-            (let [node (analyze-special ctx hname items env)
+            (let [node (analyze-special ctx sf-name items env)
                   p (form-position form)]
               (if (and p (= :def (:op node))) (assoc node :pos p) node))
           (and hname (not shadowed) (method-head? hname))
diff --git a/test/chez/corpus.edn b/test/chez/corpus.edn
index 8260b8b..40226b3 100644
--- a/test/chez/corpus.edn
+++ b/test/chez/corpus.edn
@@ -3343,4 +3343,8 @@
   {:suite "host interop / Collection.contains" :label "value membership over vector/list/set" :expected "[true false true]" :actual "[(.contains [1 2 3] 2) (.contains (list :a :b) :z) (.contains #{1 2} 1)]"}
   {:suite "host interop / clojure.lang.Util" :label "Util/hash is Java hashCode" :expected "120" :actual "(clojure.lang.Util/hash \"x\")"}
   {:suite "deftype / IObj metadata" :label "deftype meta/withMeta govern (meta x)" :expected "{:a 1}" :actual "(do (deftype Sm [m] clojure.lang.IObj (meta [_] m) (withMeta [_ n] (Sm. n))) (meta (Sm. {:a 1})))"}
+  {:suite "collections / disj" :label "disj of nil is nil" :expected "nil" :actual "(disj nil :a)"}
+  {:suite "special forms / qualified" :label "clojure.core-qualified special form (from syntax-quote)" :expected "[:g 9]" :actual "(clojure.core/letfn [(g [x] [:g x])] (g 9))"}
+  {:suite "symbols / interning" :label "(str sym) is the symbol's interned name (identity-stable)" :expected "[true true]" :actual "(let [s (quote ?a)] [(identical? (name s) (str s)) (= (str s) \"?a\")])"}
+  {:suite "symbols / interning" :label "equal symbols share an interned name string" :expected "true" :actual "(let [a (quote ?foo) b (quote ?foo)] (identical? (name a) (name b)))"}
 ]