diff --git a/src/crypto/hash/index.js b/src/crypto/hash/index.js
index 8c45d532..f9a885f1 100644
--- a/src/crypto/hash/index.js
+++ b/src/crypto/hash/index.js
@@ -38,13 +38,9 @@ function node_hash(type) {
 function hashjs_hash(hash) {
   return function(data) {
     const hashInstance = hash();
-    return stream.transform(data, (done, value) => {
-      if (!done) {
-        hashInstance.update(value);
-      } else {
-        return util.hex_to_Uint8Array(hashInstance.digest('hex'));
-      }
-    });
+    return stream.transform(data, value => {
+      hashInstance.update(value);
+    }, () => util.hex_to_Uint8Array(hashInstance.digest('hex')));
   };
 }
 
diff --git a/src/encoding/armor.js b/src/encoding/armor.js
index 6c3b2e31..a14b29c3 100644
--- a/src/encoding/armor.js
+++ b/src/encoding/armor.js
@@ -168,16 +168,11 @@ const crc_table = [
 
 function createcrc24(input) {
   let crc = 0xB704CE;
-  return stream.transform(input, (done, value) => {
-    if (!done) {
-      for (let index = 0; index < value.length; index++) {
-        crc = (crc << 8) ^ crc_table[((crc >> 16) ^ value[index]) & 0xff];
-      }
-    } else {
-      crc &= 0xffffff;
-      return new Uint8Array([crc >> 16, (crc >> 8) & 0xFF, crc & 0xFF]);
+  return stream.transform(input, value => {
+    for (let index = 0; index < value.length; index++) {
+      crc = (crc << 8) ^ crc_table[((crc >> 16) ^ value[index]) & 0xff];
     }
-  });
+  }, () => new Uint8Array([crc >> 16, crc >> 8, crc]));
 }
 
 /**
diff --git a/src/encoding/base64.js b/src/encoding/base64.js
index 3d735d79..135fd757 100644
--- a/src/encoding/base64.js
+++ b/src/encoding/base64.js
@@ -39,56 +39,55 @@ function s2r(t, u = false) {
   let l = 0;
   let s = 0;
 
-  return stream.transform(t, (done, value) => {
+  return stream.transform(t, value => {
     const r = [];
-
-    if (!done) {
-      const tl = value.length;
-      for (let n = 0; n < tl; n++) {
-        c = value[n];
-        if (s === 0) {
-          r.push(b64[(c >> 2) & 63]);
-          a = (c & 3) << 4;
-        } else if (s === 1) {
-          r.push(b64[a | ((c >> 4) & 15)]);
-          a = (c & 15) << 2;
-        } else if (s === 2) {
-          r.push(b64[a | ((c >> 6) & 3)]);
-          l += 1;
-          if ((l % 60) === 0 && !u) {
-            r.push(10); // "\n"
-          }
-          r.push(b64[c & 63]);
-        }
+    const tl = value.length;
+    for (let n = 0; n < tl; n++) {
+      c = value[n];
+      if (s === 0) {
+        r.push(b64[(c >> 2) & 63]);
+        a = (c & 3) << 4;
+      } else if (s === 1) {
+        r.push(b64[a | ((c >> 4) & 15)]);
+        a = (c & 15) << 2;
+      } else if (s === 2) {
+        r.push(b64[a | ((c >> 6) & 3)]);
         l += 1;
         if ((l % 60) === 0 && !u) {
           r.push(10); // "\n"
         }
+        r.push(b64[c & 63]);
+      }
+      l += 1;
+      if ((l % 60) === 0 && !u) {
+        r.push(10); // "\n"
+      }
 
-        s += 1;
-        if (s === 3) {
-          s = 0;
-        }
+      s += 1;
+      if (s === 3) {
+        s = 0;
       }
-    } else {
-      if (s > 0) {
-        r.push(b64[a]);
-        l += 1;
-        if ((l % 60) === 0 && !u) {
-          r.push(10); // "\n"
-        }
-        if (!u) {
-          r.push(61); // "="
-          l += 1;
-        }
+    }
+    return new Uint8Array(r);
+  }, () => {
+    const r = [];
+    if (s > 0) {
+      r.push(b64[a]);
+      l += 1;
+      if ((l % 60) === 0 && !u) {
+        r.push(10); // "\n"
       }
-      if (s === 1 && !u) {
-        if ((l % 60) === 0 && !u) {
-          r.push(10); // "\n"
-        }
+      if (!u) {
         r.push(61); // "="
+        l += 1;
       }
     }
+    if (s === 1 && !u) {
+      if ((l % 60) === 0 && !u) {
+        r.push(10); // "\n"
+      }
+      r.push(61); // "="
+    }
     return new Uint8Array(r);
   });
 }
@@ -108,22 +107,20 @@ function r2s(t, u) {
   let s = 0;
   let a = 0;
 
-  return stream.transform(t, (done, value) => {
-    if (!done) {
-      const r = [];
-      const tl = value.length;
-      for (let n = 0; n < tl; n++) {
-        c = b64.indexOf(value[n]);
-        if (c >= 0) {
-          if (s) {
-            r.push(a | ((c >> (6 - s)) & 255));
-          }
-          s = (s + 2) & 7;
-          a = (c << s) & 255;
+  return stream.transform(t, value => {
+    const r = [];
+    const tl = value.length;
+    for (let n = 0; n < tl; n++) {
+      c = b64.indexOf(value[n]);
+      if (c >= 0) {
+        if (s) {
+          r.push(a | ((c >> (6 - s)) & 255));
         }
+        s = (s + 2) & 7;
+        a = (c << s) & 255;
       }
-      return new Uint8Array(r);
     }
+    return new Uint8Array(r);
   });
 }
 
diff --git a/src/packet/packetlist.js b/src/packet/packetlist.js
index b78b9bc0..05644417 100644
--- a/src/packet/packetlist.js
+++ b/src/packet/packetlist.js
@@ -80,22 +80,18 @@ List.prototype.write = function () {
       let bufferLength = 0;
       const minLength = 512;
       arr.push(packetParser.writeTag(this[i].tag));
-      arr.push(stream.transform(packetbytes, (done, value) => {
-        if (!done) {
-          buffer.push(value);
-          bufferLength += value.length;
-          if (bufferLength >= minLength) {
-            const powerOf2 = Math.min(Math.log(bufferLength) / Math.LN2 | 0, 30);
-            const chunkSize = 2 ** powerOf2;
-            const bufferConcat = util.concatUint8Array([packetParser.writePartialLength(powerOf2)].concat(buffer));
-            buffer = [bufferConcat.subarray(1 + chunkSize)];
-            bufferLength = buffer[0].length;
-            return bufferConcat.subarray(0, 1 + chunkSize);
-          }
-        } else {
-          return util.concatUint8Array([packetParser.writeSimpleLength(bufferLength)].concat(buffer));
+      arr.push(stream.transform(packetbytes, value => {
+        buffer.push(value);
+        bufferLength += value.length;
+        if (bufferLength >= minLength) {
+          const powerOf2 = Math.min(Math.log(bufferLength) / Math.LN2 | 0, 30);
+          const chunkSize = 2 ** powerOf2;
+          const bufferConcat = util.concatUint8Array([packetParser.writePartialLength(powerOf2)].concat(buffer));
+          buffer = [bufferConcat.subarray(1 + chunkSize)];
+          bufferLength = buffer[0].length;
+          return bufferConcat.subarray(0, 1 + chunkSize);
         }
-      }));
+      }, () => util.concatUint8Array([packetParser.writeSimpleLength(bufferLength)].concat(buffer))));
     } else {
       arr.push(packetParser.writeHeader(this[i].tag, packetbytes.length));
       arr.push(packetbytes);
diff --git a/src/packet/sym_encrypted_integrity_protected.js b/src/packet/sym_encrypted_integrity_protected.js
index d80a664c..8bcced81 100644
--- a/src/packet/sym_encrypted_integrity_protected.js
+++ b/src/packet/sym_encrypted_integrity_protected.js
@@ -158,12 +158,7 @@ function aesEncrypt(algo, pt, key) {
     return nodeEncrypt(algo, pt, key);
   } // asm.js fallback
   const cfb = new AES_CFB_Encrypt(key);
-  return stream.transform(pt, (done, value) => {
-    if (!done) {
-      return cfb.process(value).result;
-    }
-    return cfb.finish().result;
-  });
+  return stream.transform(pt, value => cfb.process(value).result, () => cfb.finish().result);
 }
 
 function aesDecrypt(algo, ct, key) {
@@ -172,12 +167,7 @@ function aesDecrypt(algo, ct, key) {
     pt = nodeDecrypt(algo, ct, key);
   } else { // asm.js fallback
     const cfb = new AES_CFB_Decrypt(key);
-    pt = stream.transform(ct, (done, value) => {
-      if (!done) {
-        return cfb.process(value).result;
-      }
-      return cfb.finish().result;
-    });
+    pt = stream.transform(ct, value => cfb.process(value).result, () => cfb.finish().result);
   }
   return stream.subarray(pt, crypto.cipher[algo].blockSize + 2); // Remove random prefix
 }
diff --git a/src/stream.js b/src/stream.js
index 274a1b4a..8eba2921 100644
--- a/src/stream.js
+++ b/src/stream.js
@@ -21,14 +21,14 @@ function getReader(input) {
   return new Reader(input);
 }
 
-function transform(input, fn) {
+function transform(input, process = () => undefined, finish = () => undefined) {
   if (util.isStream(input)) {
     const reader = getReader(input);
     return new ReadableStream({
       async pull(controller) {
         try {
           const { done, value } = await reader.read();
-          const result = await fn(done, value);
+          const result = await (!done ? process : finish)(value);
           if (result) controller.enqueue(result);
           else if (!done) await this.pull(controller); // ??? Chrome bug?
           if (done) controller.close();
@@ -38,8 +38,8 @@ function transform(input, fn) {
       }
     });
   }
-  const result1 = fn(false, input);
-  const result2 = fn(true, undefined);
+  const result1 = process(input);
+  const result2 = finish(undefined);
   if (result1 && result2) return util.concatUint8Array([result1, result2]);
   return result1 || result2;
 }
diff --git a/src/util.js b/src/util.js
index a7b6701a..fe60b339 100644
--- a/src/util.js
+++ b/src/util.js
@@ -29,7 +29,7 @@ import rfc2822 from 'address-rfc2822';
 import config from './config';
 import util from './util'; // re-import module to access util functions
 import b64 from './encoding/base64';
-import Stream from './stream';
+import stream from './stream';
 
 const isIE11 = typeof navigator !== 'undefined' && !!navigator.userAgent.match(/Trident\/7\.0.*rv:([0-9.]+).*\).*Gecko$/);
 
@@ -290,7 +290,7 @@ export default {
     let totalLength = 0;
     for (let i = 0; i < arrays.length; i++) {
       if (util.isStream(arrays[i])) {
-        return Stream.concat(arrays);
+        return stream.concat(arrays);
       }
       if (!util.isUint8Array(arrays[i])) {
         throw new Error('concatUint8Array: Data must be in the form of a Uint8Array');
@@ -628,11 +628,7 @@ export default {
    * Normalize line endings to \r\n
    */
   canonicalizeEOL: function(text) {
-    return stream.transform(text, (done, value) => {
-      if (!done) {
-        return value.replace(/\r\n/g, "\n").replace(/\r/g, "\n").replace(/\n/g, "\r\n");
-      }
-    });
+    return stream.transform(text, value => value.replace(/\r\n/g, "\n").replace(/\r/g, "\n").replace(/\n/g, "\r\n"));
   },
 
   /**