diff --git a/src/jolt/clojure/edn.clj b/src/jolt/clojure/edn.clj
index ea271b3..5181e99 100644
--- a/src/jolt/clojure/edn.clj
+++ b/src/jolt/clojure/edn.clj
@@ -10,10 +10,15 @@
 ;; maps/vectors/lists. (Lists stay lists — EDN never evaluates them as code.)
 (defn- edn->value [x]
   (cond
-    (and (map? x) (= :jolt/set (get x :jolt/type))) (set (map edn->value (get x :value)))
-    ;; Only untagged structs are real maps; symbols/chars/tagged literals are also
-    ;; struct? (=> map?) but carry a :jolt/type and must pass through unchanged.
-    (and (map? x) (nil? (get x :jolt/type)))
+    ;; Reader FORMS are detected by :jolt/type tag, never by map? — strict map?
+    ;; (correctly) excludes tagged structs, so the old (and (map? x) ...) guard
+    ;; would skip them.
+    (= :jolt/set (get x :jolt/type)) (set (map edn->value (get x :value)))
+    ;; EDN built-in tagged elements (#uuid/#inst, plus registered readers):
+    ;; apply the data reader to the read form (no evaluation involved).
+    (= :jolt/tagged (get x :jolt/type))
+      (__read-tagged (get x :tag) (edn->value (get x :form)))
+    (map? x)
       (into {} (map (fn [e] [(edn->value (key e)) (edn->value (val e))]) x))
     (vector? x) (mapv edn->value x)
     (seq? x) (map edn->value x)
diff --git a/src/jolt/evaluator.janet b/src/jolt/evaluator.janet
index 6d743de..a860cb0 100644
--- a/src/jolt/evaluator.janet
+++ b/src/jolt/evaluator.janet
@@ -1112,6 +1112,15 @@
           the-form))
       the-form)))
   (ns-intern core "macroexpand-1" expand-1)
+  # Apply a registered data reader to an already-read form (EDN built-in tags
+  # #uuid/#inst and any registered reader). Throws on an unknown tag.
+  (ns-intern core "__read-tagged"
+    (fn [tag form]
+      (def data-readers (get (ctx :env) :data-readers))
+      (def reader-fn (if data-readers (get data-readers tag)))
+      (if reader-fn
+        (reader-fn form)
+        (error (string "No reader function for tag " tag)))))
   # macroexpand: expand repeatedly until the head is no longer a macro (the
   # form's SUBFORMS are not expanded, matching Clojure).
   (ns-intern core "macroexpand"
diff --git a/test/integration/clojure-stdlib-suite-test.janet b/test/integration/clojure-stdlib-suite-test.janet
index 1b4417e..c98f8bc 100644
--- a/test/integration/clojure-stdlib-suite-test.janet
+++ b/test/integration/clojure-stdlib-suite-test.janet
@@ -15,7 +15,7 @@
    # clojure.edn reads via clojure.core/read-string (opts/:eof + nil/blank) and
    # constructs set/nested values. Only #uuid remains (no real uuid type) —
    # jolt-b7y. Guard the passing subset.
-   ["clojure/edn_test/read_string.cljc"      49 false]])
+   ["clojure/edn_test/read_string.cljc"      50 false]])
 
 (def root "test/clojure-stdlib")
 (def per-file-timeout 6)