Try (and fail) to repro thread issue.

evparallel.janet

(defn parallel
  [jobs]
  (print "Beginning " (length jobs) " jobs...")
  (let [results-chan (ev/thread-chan 0)
        res @{}]
    (each job jobs
      (ev/thread (fiber/new job) results-chan :n))

    (while (< (length res) (length jobs))
      (let [[k v] (ev/take results-chan)]
        (print "job " k " finished")
        (put res k v)))

    (print "Finished jobs.")
    res))

(defn randsleep
  []
  (math/seedrandom (os/cryptorand 16))
  (os/sleep (math/random)))

(def jobs
  [(fn [x] (randsleep) (ev/give x [:a "A"]))
   (fn [x] (randsleep) (ev/give x [:b "B"]))
   (fn [x] (randsleep) (ev/give x [:c stdout]))
   (fn [x] (randsleep) (ev/give x [:d "D"]))])

(pp (parallel jobs))