diff --git a/src/reagent/impl/batching.cljs b/src/reagent/impl/batching.cljs
index ba6ee35..53c1fc7 100644
--- a/src/reagent/impl/batching.cljs
+++ b/src/reagent/impl/batching.cljs
@@ -24,7 +24,7 @@
           fake-raf))))
 
 (defn compare-mount-order
-  [c1 c2]
+  [^clj c1 ^clj c2]
   ;; Mount order is now set in DidMount method.  I.e. the
   ;; top-most component is mounted last and gets largest
   ;; number. This is reverse compared to WillMount where method
@@ -49,7 +49,7 @@
   (dotimes [i (alength fs)]
     ((aget fs i))))
 
-(defn enqueue [queue fs f]
+(defn enqueue [^clj queue fs f]
   (assert-some f "Enqueued function")
   (.push fs f)
   (.schedule queue))
@@ -109,12 +109,12 @@
 (defn flush-after-render []
   (.flush-after-render render-queue))
 
-(defn queue-render [c]
+(defn queue-render [^clj c]
   (when-not (.-cljsIsDirty c)
     (set! (.-cljsIsDirty c) true)
     (.queue-render render-queue c)))
 
-(defn mark-rendered [c]
+(defn mark-rendered [^clj c]
   (set! (.-cljsIsDirty c) false))
 
 (defn do-before-flush [f]
diff --git a/src/reagent/impl/component.cljs b/src/reagent/impl/component.cljs
index b571c28..5ab6393 100644
--- a/src/reagent/impl/component.cljs
+++ b/src/reagent/impl/component.cljs
@@ -64,19 +64,19 @@
   (and (fn? c)
        (some? (some-> c (.-prototype) (.-render)))))
 
-(defn ^boolean reagent-component? [c]
+(defn ^boolean reagent-component? [^clj c]
   (some? (.-reagentRender c)))
 
-(defn cached-react-class [c]
+(defn cached-react-class [^clj c]
   (.-cljsReactClass c))
 
-(defn cache-react-class [c constructor]
+(defn cache-react-class [^clj c constructor]
   (set! (.-cljsReactClass c) constructor))
 
 
 ;;; State
 
-(defn state-atom [this]
+(defn state-atom [^clj this]
   (let [sa (.-cljsState this)]
     (if-not (nil? sa)
       sa
@@ -95,7 +95,7 @@
      2) Function (form-2 component) - updates the render function to `res` i.e. the internal function
         and calls wrap-render again (`recur`), until the render result doesn't evaluate to a function.
      3) Anything else - Returns the result of evaluating `c`"
-  [c]
+  [^clj c]
   (let [f (.-reagentRender c)
         _ (assert-callable f)
         ;; cljsLegacyRender tells if this calls was defined
@@ -150,7 +150,7 @@
      ;; TODO: Use static property for cljsRatom
      (this-as c (if util/*non-reactive*
                   (do-render c)
-                  (let [rat (gobj/get c "cljsRatom")]
+                  (let [^clj rat (gobj/get c "cljsRatom")]
                     (batch/mark-rendered c)
                     (if (nil? rat)
                       (ratom/run-in-reaction #(do-render c) c "cljsRatom"
@@ -232,7 +232,7 @@
       (this-as c
         ;; This method is called after everything inside the
         ;; has been mounted. This is reverse compared to WillMount.
-        (set! (.-cljsMountOrder c) (batch/next-mount-count))
+        (set! (.-cljsMountOrder ^clj c) (batch/next-mount-count))
         (when-not (nil? f)
           (.call f c c))))
 
@@ -347,13 +347,13 @@
     ;; These names SHOULD be mangled by Closure so we can't use goog/extend
 
     (when (:render body)
-      (set! (.-render (.-prototype cmp)) (:render body)))
+      (set! (.-render ^js (.-prototype cmp)) (:render body)))
 
     (when (:reagentRender body)
-      (set! (.-reagentRender (.-prototype cmp)) (:reagentRender body)))
+      (set! (.-reagentRender ^clj (.-prototype cmp)) (:reagentRender body)))
 
     (when (:cljsLegacyRender body)
-      (set! (.-cljsLegacyRender (.-prototype cmp)) (:cljsLegacyRender body)))
+      (set! (.-cljsLegacyRender ^clj (.-prototype cmp)) (:cljsLegacyRender body)))
 
     (gobj/extend cmp react/Component static-methods)
 
diff --git a/src/reagent/impl/template.cljs b/src/reagent/impl/template.cljs
index bba707b..7f3f427 100644
--- a/src/reagent/impl/template.cljs
+++ b/src/reagent/impl/template.cljs
@@ -112,7 +112,7 @@
       class
       (assoc :class (util/class-names class (:class props))))))
 
-(defn convert-props [props id-class]
+(defn convert-props [props ^clj id-class]
   (let [class (:class props)
         props (-> props
                   (cond-> class (assoc :class (util/class-names class)))
@@ -139,7 +139,7 @@
 (declare input-component-set-value)
 
 (defn input-node-set-value
-  [node rendered-value dom-value component {:keys [on-write]}]
+  [node rendered-value dom-value ^clj component {:keys [on-write]}]
   (if-not (and (identical? node (.-activeElement js/document))
             (has-selection-api? (.-type node))
             (string? rendered-value)
@@ -187,7 +187,7 @@
           (set! (.-selectionStart node) new-cursor-offset)
           (set! (.-selectionEnd node) new-cursor-offset))))))
 
-(defn input-component-set-value [this]
+(defn input-component-set-value [^clj this]
   (when (.-cljsInputLive this)
     (set! (.-cljsInputDirty this) false)
     (let [rendered-value (.-cljsRenderedValue this)
@@ -197,7 +197,7 @@
       (when (not= rendered-value dom-value)
         (input-node-set-value node rendered-value dom-value this {})))))
 
-(defn input-handle-change [this on-change e]
+(defn input-handle-change [^clj this on-change e]
   (set! (.-cljsDOMValue this) (-> e .-target .-value))
   ;; Make sure the input is re-rendered, in case on-change
   ;; wants to keep the value unchanged
@@ -207,7 +207,7 @@
   (on-change e))
 
 (defn input-render-setup
-  [this jsprops]
+  [^clj this ^js jsprops]
   ;; Don't rely on React for updating "controlled inputs", since it
   ;; doesn't play well with async rendering (misses keystrokes).
   (when (and (some? jsprops)
@@ -227,7 +227,7 @@
       (set! (.-defaultValue jsprops) value)
       (set! (.-onChange jsprops) #(input-handle-change this on-change %)))))
 
-(defn input-unmount [this]
+(defn input-unmount [^clj this]
   (set! (.-cljsInputLive this) nil))
 
 (defn ^boolean input-component? [x]
@@ -396,7 +396,7 @@
 (defn expand-seq [s]
   (into-array (map as-element s)))
 
-(defn expand-seq-dev [s o]
+(defn expand-seq-dev [s ^clj o]
   (into-array (map (fn [val]
                      (when (and (vector? val)
                                 (nil? (key-from-vec val)))
diff --git a/src/reagent/impl/util.cljs b/src/reagent/impl/util.cljs
index f51b418..7712c96 100644
--- a/src/reagent/impl/util.cljs
+++ b/src/reagent/impl/util.cljs
@@ -107,7 +107,7 @@
   (-invoke [_ a b c d e f g h i j k l m n o p q r s t rest]
     (apply pfn a b c d e f g h i j k l m n o p q r s t rest))
   IEquiv
-  (-equiv [_ other]
+  (-equiv [_ ^clj other]
     (and (instance? PartialFn other)
          (= f (.-f other))
          (= args (.-args other))))
diff --git a/src/reagent/ratom.cljs b/src/reagent/ratom.cljs
index 1974fa5..37885fd 100644
--- a/src/reagent/ratom.cljs
+++ b/src/reagent/ratom.cljs
@@ -47,7 +47,7 @@
 
    Inside '_update-watching' along with adding the ratoms in 'r.watching' of reaction,
    the reaction is also added to the list of watches on each ratoms f derefs."
-  [f r]
+  [f ^clj r]
   (set! (.-captured r) nil)
   (when (dev?)
     (set! (.-ratomGeneration r) (set! generation (inc generation))))
@@ -75,17 +75,17 @@
     (swap! -running + (- (count new) (count old))))
   new)
 
-(defn- add-w [this key f]
+(defn- add-w [^clj this key f]
   (let [w (.-watches this)]
     (set! (.-watches this) (check-watches w (assoc w key f)))
     (set! (.-watchesArr this) nil)))
 
-(defn- remove-w [this key]
+(defn- remove-w [^clj this key]
   (let [w (.-watches this)]
     (set! (.-watches this) (check-watches w (dissoc w key)))
     (set! (.-watchesArr this) nil)))
 
-(defn- notify-w [this old new]
+(defn- notify-w [^clj this old new]
   (let [w (.-watchesArr this)
         a (if (nil? w)
             ;; Copy watches to array for speed
@@ -188,7 +188,7 @@
 
 (declare make-reaction)
 
-(defn- cached-reaction [f o k obj destroy]
+(defn- cached-reaction [f ^clj o k ^clj obj destroy]
   (let [m (.-reagReactionCache o)
         m (if (nil? m) {} m)
         r (m k nil)]
@@ -222,7 +222,7 @@
       (cached-reaction #(apply f args) f args this nil)))
 
   IEquiv
-  (-equiv [_ other]
+  (-equiv [_ ^clj other]
     (and (instance? Track other)
          (= f (.-f other))
          (= args (.-args other))))
@@ -259,7 +259,7 @@
   IReactiveAtom
 
   IEquiv
-  (-equiv [_ other]
+  (-equiv [_ ^clj other]
     (and (instance? RCursor other)
          (= path (.-path other))
          (= ratom (.-ratom other))))
@@ -316,7 +316,7 @@
   (-hash [_] (hash [ratom path])))
 
 (defn cursor
-  [src path]
+  [^clj src path]
   (assert (or (satisfies? IReactiveAtom src)
               (and (ifn? src)
                    (not (vector? src))))
@@ -347,7 +347,7 @@
 (defprotocol IRunnable
   (run [this]))
 
-(defn- handle-reaction-change [this sender old new]
+(defn- handle-reaction-change [^clj this sender old new]
   (._handle-change this sender old new))
 
 ;; Fields of a Reaction javascript object
@@ -578,7 +578,7 @@
   (-swap! [a f x y more] (-reset! a (apply f state x y more)))
 
   IEquiv
-  (-equiv [_ other]
+  (-equiv [_ ^clj other]
           (and (instance? Wrapper other)
                ;; If either of the wrappers have changed, equality
                ;; cannot be relied on.
diff --git a/test/reagenttest/testreagent.cljs b/test/reagenttest/testreagent.cljs
index 2d36802..cf82b31 100644
--- a/test/reagenttest/testreagent.cljs
+++ b/test/reagenttest/testreagent.cljs
@@ -1318,7 +1318,7 @@
                        :get-derived-state-from-error (fn [error]
                                                        #js {:hasError true})
                        :component-did-catch (fn [this e info])
-                       :render (fn [this]
+                       :render (fn [^js/React.Component this]
                                  (r/as-element (if (.-hasError (.-state this))
                                                  [:p "Error"]
                                                  (into [:<>] (r/children this)))))})