diff --git a/implementations/javascript/package.json b/implementations/javascript/package.json
index 406bb29..9099956 100644
--- a/implementations/javascript/package.json
+++ b/implementations/javascript/package.json
@@ -1,6 +1,6 @@
 {
   "name": "preserves",
-  "version": "0.2.0",
+  "version": "0.3.0",
   "description": "Experimental data serialization format",
   "homepage": "https://gitlab.com/preserves/preserves",
   "license": "Apache-2.0",
diff --git a/implementations/javascript/src/codec.js b/implementations/javascript/src/codec.js
index 523c63a..9888270 100644
--- a/implementations/javascript/src/codec.js
+++ b/implementations/javascript/src/codec.js
@@ -28,7 +28,6 @@ class Decoder {
       ? (packet._view || packet) // strip off Bytes wrapper, if any
       : new Uint8Array(0);
     this.index = 0;
-    this.placeholders = fromJS(options.placeholders || {});
     this.includeAnnotations = options.includeAnnotations || false;
   }
 
@@ -86,10 +85,16 @@ class Decoder {
   binarystream(minor) {
     const result = [];
     while (!this.peekend()) {
-      const chunk = this.next();
+      const chunk = Annotations.stripAnnotations(this.next());
       if (ArrayBuffer.isView(chunk)) {
+        if (chunk.byteLength == 0) {
+          throw new DecodeError("Empty binary chunks are forbidden");
+        }
         result.push(new Uint8Array(chunk.buffer, chunk.byteOffset, chunk.byteLength));
       } else if (chunk instanceof Bytes) {
+        if (chunk._view.length == 0) {
+          throw new DecodeError("Empty binary chunks are forbidden");
+        }
         result.push(chunk._view);
       } else {
         const e = new DecodeError("Unexpected non-binary chunk");
@@ -176,16 +181,7 @@ class Decoder {
                 }
                 default: throw new DecodeError("Illegal format A lead byte");
               }
-            case 1: {
-              const n = this.wirelength(arg);
-              const v = this.placeholders.get(n, void 0);
-              if (typeof v === 'undefined') {
-                const e = new DecodeError("Invalid Preserves placeholder");
-                e.irritant = n;
-                throw e;
-              }
-              return this.wrap(v);
-            }
+            case 1: throw new DecodeError("Illegal format A lead byte");
             case 2: {
               const t = arg >> 2;
               const n = arg & 3;
@@ -243,7 +239,6 @@ class Encoder {
     this.chunks = [];
     this.view = new DataView(new ArrayBuffer(256));
     this.index = 0;
-    this.placeholders = fromJS(options.placeholders || {});
   }
 
   contents() {
@@ -327,11 +322,7 @@ class Encoder {
   }
 
   push(v) {
-    const placeholder = this.placeholders.get(v, void 0);
-    if (typeof placeholder !== 'undefined') {
-      this.header(0, 1, placeholder);
-    }
-    else if (typeof v === 'object' && v !== null && typeof v[PreserveOn] === 'function') {
+    if (typeof v === 'object' && v !== null && typeof v[PreserveOn] === 'function') {
       v[PreserveOn](this);
     }
     else if (typeof v === 'boolean') {
diff --git a/implementations/javascript/test/test-codec.js b/implementations/javascript/test/test-codec.js
index 124ea73..10c20ef 100644
--- a/implementations/javascript/test/test-codec.js
+++ b/implementations/javascript/test/test-codec.js
@@ -81,22 +81,16 @@ describe('common test suite', () => {
   const samples_bin = fs.readFileSync(__dirname + '/../../../tests/samples.bin');
   const samples = decodeWithAnnotations(samples_bin);
 
-  const TestCases = Record.makeConstructor('TestCases', ['mapping', 'cases']);
-  const ExpectedPlaceholderMapping =
-        Record.makeConstructor('ExpectedPlaceholderMapping', ['table']);
-
-  const expectedPlaceholderMapping = TestCases._mapping(samples.peel()).strip();
-  const placeholders_decode = ExpectedPlaceholderMapping._table(expectedPlaceholderMapping);
-  const placeholders_encode = placeholders_decode.mapEntries((e) => [e[1],e[0]]);
+  const TestCases = Record.makeConstructor('TestCases', ['cases']);
 
   function DS(bs) {
-    return decode(bs, {placeholders: placeholders_decode});
+    return decode(bs);
   }
   function D(bs) {
-    return decodeWithAnnotations(bs, {placeholders: placeholders_decode});
+    return decodeWithAnnotations(bs);
   }
   function E(v) {
-    return encode(v, {placeholders: placeholders_encode});
+    return encode(v);
   }
 
   const expectedValues = {
@@ -208,6 +202,7 @@ describe('common test suite', () => {
           });
         });
         break;
+      case Symbol.for('DecodeEOF'): // fall through
       case Symbol.for('DecodeShort'):
         describe(tName, () => {
           it('should fail with ShortPacket', () => {
@@ -221,6 +216,7 @@ describe('common test suite', () => {
         });
         break;
       case Symbol.for('ParseError'):
+      case Symbol.for('ParseEOF'):
       case Symbol.for('ParseShort'):
         /* Skipped for now, until we have an implementation of text syntax */
         break;