diff --git a/KaitaiStream.d.ts b/KaitaiStream.d.ts
new file mode 100644
index 0000000..e922af7
--- /dev/null
+++ b/KaitaiStream.d.ts
@@ -0,0 +1,198 @@
+export = KaitaiStream.KaitaiStream;
+
+export as namespace KaitaiStream;
+
+declare namespace KaitaiStream {
+  class EOFError extends Error {
+    bytesReq: number;
+    bytesAvail: number;
+    constructor(bytesReq: number, bytesAvail: number);
+  }
+
+  class UnexpectedDataError extends Error {
+    expected: any;
+    actual: any;
+    constructor(expected: any, actual: any);
+  }
+
+  class UndecidedEndiannessError extends Error {
+    constructor();
+  }
+
+  class KaitaiStream {
+      pos: number;
+      bits: number;
+      bitsLeft: number;
+      /**
+        KaitaiStream is an implementation of Kaitai Struct API for JavaScript.
+        Based on DataStream - https://github.com/kig/DataStream.js
+    
+        @param arrayBuffer ArrayBuffer to read from.
+        @param byteOffset Offset from arrayBuffer beginning for the KaitaiStream.
+        */
+      constructor(arrayBuffer: ArrayBufferLike, byteOffset?: number);
+      /**
+        Dependency configuration data. Holds urls for (optional) dynamic loading
+        of code dependencies from a remote server. For use by (static) processing functions.
+    
+        Caller should the supported keys to the asset urls as needed.
+        NOTE: `depUrls` is a static property of KaitaiStream (the factory),like the various
+              processing functions. It is NOT part of the prototype of instances.
+        */
+      static depUrls: {
+          zlib: string;
+      };
+      /**
+        Virtual byte length of the KaitaiStream backing buffer.
+        Updated to be max of original buffer size and last written size.
+        If dynamicSize is false is set to buffer size.
+        */
+      _byteLength: number;
+      /**
+        Set/get the backing ArrayBuffer of the KaitaiStream object.
+        The setter updates the DataView to point to the new buffer.
+        */
+      buffer: ArrayBuffer;
+      /**
+        Set/get the byteOffset of the KaitaiStream object.
+        The setter updates the DataView to point to the new byteOffset.
+        */
+      byteOffset: number;
+      /**
+        Set/get the backing DataView of the KaitaiStream object.
+        The setter updates the buffer and byteOffset to point to the DataView values.
+        */
+      dataView: DataView;
+      /**
+        Returns true if the KaitaiStream seek pointer is at the end of buffer and
+        there's no more data to read.
+    
+        @return True if the seek pointer is at the end of the buffer.
+        */
+      isEof(): boolean;
+      /**
+        Sets the KaitaiStream read/write position to given position.
+        Clamps between 0 and KaitaiStream length.
+    
+        @param pos Position to seek to.
+        */
+      seek(pos: number): void;
+      /**
+        Returns the byte length of the KaitaiStream object.
+        */
+      readonly size: number;
+      /**
+        Reads an 8-bit signed int from the stream.
+        @return The read number.
+      */
+      readS1(): number;
+      /**
+        Reads a 16-bit big-endian signed int from the stream.
+        @return The read number.
+      */
+      readS2be(): number;
+      /**
+        Reads a 32-bit big-endian signed int from the stream.
+        @return The read number.
+      */
+      readS4be(): number;
+      /**
+        Reads a 64-bit big-endian unsigned int from the stream. Note that
+        JavaScript does not support 64-bit integers natively, so it will
+        automatically upgrade internal representation to use IEEE 754
+        double precision float.
+        @return The read number.
+      */
+      readS8be(): number;
+      /**
+        Reads a 16-bit little-endian signed int from the stream.
+        @return The read number.
+      */
+      readS2le(): number;
+      /**
+        Reads a 32-bit little-endian signed int from the stream.
+        @return The read number.
+      */
+      readS4le(): number;
+      /**
+        Reads a 64-bit little-endian unsigned int from the stream. Note that
+        JavaScript does not support 64-bit integers natively, so it will
+        automatically upgrade internal representation to use IEEE 754
+        double precision float.
+        @return The read number.
+      */
+      readS8le(): number;
+      /**
+        Reads an 8-bit unsigned int from the stream.
+        @return {number} The read number.
+      */
+      readU1(): number;
+      /**
+        Reads a 16-bit big-endian unsigned int from the stream.
+        @return The read number.
+      */
+      readU2be(): number;
+      /**
+        Reads a 32-bit big-endian unsigned int from the stream.
+        @return The read number.
+      */
+      readU4be(): number;
+      /**
+        Reads a 64-bit big-endian unsigned int from the stream. Note that
+        JavaScript does not support 64-bit integers natively, so it will
+        automatically upgrade internal representation to use IEEE 754
+        double precision float.
+        @return The read number.
+      */
+      readU8be(): number;
+      /**
+        Reads a 16-bit little-endian unsigned int from the stream.
+        @return The read number.
+      */
+      readU2le(): number;
+      /**
+        Reads a 32-bit little-endian unsigned int from the stream.
+        @return The read number.
+      */
+      readU4le(): number;
+      /**
+        Reads a 64-bit little-endian unsigned int from the stream. Note that
+        JavaScript does not support 64-bit integers natively, so it will
+        automatically upgrade internal representation to use IEEE 754
+        double precision float.
+        @return The read number.
+      */
+      readU8le(): number;
+      readF4be(): number;
+      readF8be(): number;
+      readF4le(): number;
+      readF8le(): number;
+      alignToByte(): void;
+      readBitsInt(n: number): number;
+      /**
+        Native endianness. Either KaitaiStream.BIG_ENDIAN or KaitaiStream.LITTLE_ENDIAN
+        depending on the platform endianness.
+      */
+      static endianness: boolean;
+      readBytes(len: number): Uint8Array;
+      readBytesFull(): Uint8Array;
+      readBytesTerm(terminator: any, include: any, consume: any, eosError: any): any;
+      ensureFixedContents(expected: any): Uint8Array;
+      static bytesStripRight(data: any, padByte: any): any;
+      static bytesTerminate(data: any, term: any, include: any): any;
+      static bytesToStr(arr: Uint8Array, encoding: string): any;
+      static processXorOne(data: any, key: any): Uint8Array;
+      static processXorMany(data: any, key: any): Uint8Array;
+      static processRotateLeft(data: any, amount: any, groupSize: any): Uint8Array;
+      static processZlib(buf: Uint8Array): any;
+      static mod(a: any, b: any): number;
+      static arrayMin(arr: any): any;
+      static arrayMax(arr: any): any;
+      static byteArrayCompare(a: any, b: any): number;
+      
+      static EOFError: typeof EOFError;
+      static UnexpectedDataError: typeof UnexpectedDataError;
+      static UndecidedEndiannessError: typeof UndecidedEndiannessError;
+  }
+}
+
diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..fbf55ee
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,3 @@
+import KaitaiStream from './KaitaiStream';
+
+export { KaitaiStream };
diff --git a/package.json b/package.json
index e9f46ba..9f6e60e 100644
--- a/package.json
+++ b/package.json
@@ -3,6 +3,7 @@
   "version": "0.8.0-SNAPSHOT.11",
   "description": "Kaitai Struct: runtime library for Javascript",
   "main": "index.js",
+  "types": "index.d.ts",
   "repository": {
     "type": "git",
     "url": "git+https://github.com/kaitai-io/kaitai_struct_javascript_runtime.git"