diff --git a/test-resources/bytechannel_and_related_classes.bb b/test-resources/bytechannel_and_related_classes.bb
index 7c8775d7..4b69076b 100644
--- a/test-resources/bytechannel_and_related_classes.bb
+++ b/test-resources/bytechannel_and_related_classes.bb
@@ -1,132 +1,23 @@
 (ns bytechannel-and-related-classes
-  (:import (java.io InputStream OutputStream)
-           (java.nio ByteBuffer)
+  (:require [clojure.java.io :as io])
+  (:import (java.nio.file OpenOption
+                          StandardOpenOption)
            (java.nio.channels ByteChannel
+                              FileChannel
+                              ReadableByteChannel
+                              WritableByteChannel
                               Channels)))
 
-;;
-;; Accept a ByteChannel and return an InputStream that reads data from
-;; the given ByteChannel. Buffer data in internal ByteBuffer.
-;;
-
-
-(defn channel->input-stream ^InputStream [^ByteChannel ch]
-  (let [buffer (doto (ByteBuffer/allocate 1024)
-                 (.flip))
-        eof?   (fn []
-                 (if (.hasRemaining buffer)
-                   ;; Buffer has data that can be read:
-                   false
-                   ;; Buffer is empty, try fill buffer from channel:
-                   (do (.clear buffer)
-                       (if (= (.read ch buffer) -1)
-                         ;; Channel is also empty
-                         true
-                         ;; Successfully read data into buffer:
-                         (do (.flip buffer)
-                             false)))))]
-    (proxy [InputStream] []
-      (read
-        ([]
-         (if (eof?)
-           -1
-           (-> (.get buffer)
-               (bit-and 0xff))))
-        ([b]
-         (.read this b 0 (alength b)))
-        ([b off len]
-         (if (eof?)
-           -1
-           (let [len (min (alength b)
-                          (.remaining buffer))]
-             (.get buffer b 0 len)
-             len))))
-      (close []
-        (.close ch)))))
-
-
-;;
-;; Accept a ByteChannel and return an OutputStream that writes into the
-;; channel
-;;
-
-
-(defn channel->output-stream ^OutputStream [^ByteChannel ch]
-  (proxy [OutputStream] []
-    (write
-      ([v]
-       (if (bytes? v)
-         (.write ch (ByteBuffer/wrap v))
-         (let [buffer (ByteBuffer/allocate 1)]
-           (.put buffer (-> (Integer. v) (.byteValue)))
-           (.flip buffer)
-           (.write ch buffer))))
-      ([v off len]
-       (.write ch (ByteBuffer/wrap v off len))))
-    (close []
-      (.close ch))))
-
-
-;;
-;; Tests:
-;;
-
-
-(defn read-byte-by-byte-test []
-  (let [in (-> (.getBytes "Hello")
-               (java.io.ByteArrayInputStream.)
-               (Channels/newChannel)
-               (channel->input-stream))]
-    (and (= (.read in) (int \H))
-         (= (.read in) (int \e))
-         (= (.read in) (int \l))
-         (= (.read in) (int \l))
-         (= (.read in) (int \o))
-         (= (.read in) -1))))
-
-(defn read-byte-array []
-  (let [in     (-> (.getBytes "Hello")
-                   (java.io.ByteArrayInputStream.)
-                   (Channels/newChannel)
-                   (channel->input-stream))
-        buffer (byte-array 10)
-        len    (.read in buffer)]
-    (and (= len 5)
-         (= (String. buffer 0 len) "Hello"))))
-
-(defn read-all []
-  (let [in   (-> (.getBytes "Hello")
-                 (java.io.ByteArrayInputStream.)
-                 (Channels/newChannel)
-                 (channel->input-stream))
-        data (.readAllBytes in)]
-    (= (String. data) "Hello")))
-
-(defn write-byte-by-byte []
-  (let [buffer (java.io.ByteArrayOutputStream.)
-        out    (-> (Channels/newChannel buffer)
-                   (channel->output-stream))]
-    (.write out (int \H))
-    (.write out (int \e))
-    (.write out (int \l))
-    (.write out (int \l))
-    (.write out (int \o))
-    (.close out)
-    (= (String. (.toByteArray buffer)) "Hello")))
-
-(defn write-byte-array []
-  (let [buffer (java.io.ByteArrayOutputStream.)
-        out    (-> (Channels/newChannel buffer)
-                   (channel->output-stream))]
-    (.write out (.getBytes "Hello"))
-    (.close out)
-    (= (String. (.toByteArray buffer)) "Hello")))
-
-(when (every? (fn [f] (f))
-              [read-byte-by-byte-test
-               read-byte-array
-               read-all
-               write-byte-by-byte
-               write-byte-array])
+(when (and (let [ch (-> (.getBytes "Hello")
+                        (java.io.ByteArrayInputStream.)
+                        (Channels/newChannel))]
+             (instance? ReadableByteChannel ch))
+           (let [ch (-> (java.io.ByteArrayOutputStream.)
+                        (Channels/newChannel))]
+             (instance? WritableByteChannel ch))
+           (with-open [ch (FileChannel/open (-> (io/file "README.md")
+                                                (.toPath))
+                                            (into-array OpenOption [StandardOpenOption/READ]))]
+             (instance? ByteChannel ch)))
   (println "Success")
   :success)
diff --git a/test-resources/proxy_inputstream_outputstream.bb b/test-resources/proxy_inputstream_outputstream.bb
index 16ba5182..8b2aac6f 100644
--- a/test-resources/proxy_inputstream_outputstream.bb
+++ b/test-resources/proxy_inputstream_outputstream.bb
@@ -103,12 +103,10 @@
 ;; Run all tests:
 ;;
 
-
-(when (every? (fn [f] (f))
-              [read-byte-by-byte-test
-               read-byte-array
-               read-all
-               write-byte-by-byte
-               write-byte-array])
+(when (and (read-byte-by-byte-test)
+           (read-byte-array)
+           (read-all)
+           (write-byte-by-byte)
+           (write-byte-array))
   (println "Success")
   :success)