core.typed and core.match failing to get along

lambda.clj

(ns type-test.lambda
  (require [clojure.core.typed :refer :all]
           [clojure.core.match :refer [match]]))

(def-alias Expr "An expression"
  (Rec [e]
       (U '[(Value :var) Symbol]
          '[(Value :lam) Symbol e]
          '[(Value :app) e e])))

(ann free? (Fn [Expr Symbol -> Boolean]))
(defn free? [expr var]
  (match expr
         [:var s] (= s var)
         [:lam arg body] (if (= arg var) false (free? body var))
         [:app f e] (or (free? f var) (free? e var))))

output

Initializing core.typed ...
Building core.typed base environments ...
Finished building base environments
"Elapsed time: 4171.218072 msecs"
core.typed initialized.
Start collecting type-test.lambda
Finished collecting type-test.lambda
Collected 1 namespaces in 5498.927805 msecs
Start checking type-test.lambda
Type Error (type_test/lambda.clj:13:3) Cannot get index 2 from type (HVec [(Value :var) clojure.core.typed/Symbol])
Type Checker: Found 1 error
Found errors
Subprocess failed