diff --git a/src/sci/impl/evaluator.cljc b/src/sci/impl/evaluator.cljc
index 2112b314..60d3b3c4 100644
--- a/src/sci/impl/evaluator.cljc
+++ b/src/sci/impl/evaluator.cljc
@@ -118,12 +118,12 @@
 
 (def none-sentinel #?(:clj (Object.) :cljs (js/Object.)))
 
-(defn get-from-type [instance method-str method-str-unmunged #?(:clj arg-count :cljs args)]
+(defn get-from-type [instance _method-str method-str-unmunged #?(:clj arg-count :cljs args)]
   (if (zero? #?(:clj arg-count :cljs (alength args)))
     (if (instance? sci.impl.records.SciRecord instance)
       (get instance (keyword method-str-unmunged) none-sentinel)
       (if (instance? sci.impl.deftype.SciType instance)
-        (get (types/getVal instance) (symbol method-str) none-sentinel)
+        (get (types/getVal instance) (symbol method-str-unmunged) none-sentinel)
         none-sentinel))
     none-sentinel))
 
diff --git a/test/sci/interop_test.cljc b/test/sci/interop_test.cljc
index bbbc6000..e7bf2064 100644
--- a/test/sci/interop_test.cljc
+++ b/test/sci/interop_test.cljc
@@ -379,3 +379,11 @@
      (is (= 1 (sci/eval-string "(def x #js {:foo_bar 1}) (.-foo-bar x)" {:classes {:allow :all}})))
      (is (= 1 (sci/eval-string "(def x #js {:foo_bar (fn [] 1)}) (.foo-bar x)" {:classes {:allow :all}})))
      (is (= {:foo_bar 1} (sci/eval-string "(js->clj (doto #js {} (set! -foo-bar 1)) :keywordize-keys true)" {:classes {:allow :all}})))))
+
+#?(:clj
+   (deftest issue-987-deftype-munged-fields-test
+     ;; these cases don't work in CLJS yet because {:classes {:allow :all}} takes the fast path
+     ;; perhaps we can fix this by exposing the deftype as an Object in CLJS with mutated fields
+     (is (= 1 (sci/eval-string "(deftype Foo [foo-bar]) (.-foo-bar (->Foo 1))" {:classes {:allow :all}})))
+     ;; this doesn't work yet either, but not common in Clojure
+     #_(is (= 1 (sci/eval-string "(deftype Foo [foo-bar]) (.-foo_bar (->Foo 1))" {:classes {:allow :all}})))))