diff --git a/bit-array/bit-array-tests.ts b/bit-array/bit-array-tests.ts
new file mode 100644
index 0000000000..9337c2afa9
--- /dev/null
+++ b/bit-array/bit-array-tests.ts
@@ -0,0 +1,10 @@
+/// <reference path="bit-array.d.ts" />
+
+import * as BitArray from "bit-array";
+
+const a = new BitArray(32);
+a.set(0, true);
+a.set(31, true);
+a.toString(); // "10000000000000000000000000000001"
+a.get(1); // false
+a.get(31); // true
\ No newline at end of file
diff --git a/bit-array/bit-array.d.ts b/bit-array/bit-array.d.ts
new file mode 100644
index 0000000000..e9ee31339e
--- /dev/null
+++ b/bit-array/bit-array.d.ts
@@ -0,0 +1,106 @@
+// Type definitions for bit-array v0.2.2
+// Project: https://github.com/bramstein/bit-array
+// Definitions by: Mudkip <https://github.com/mudkipme>
+// Definitions: https://github.com/mudkipme/DefinitelyTyped
+
+declare module "bit-array" {
+
+    class BitArray {
+        /**
+         * Creates a new empty BitArray with the given length or initialises the BitArray with the given hex representation.
+         */
+        constructor(size: number, hex?: string);
+
+        /**
+         * Returns the total number of bits in this BitArray.
+         */
+        size(): number;
+
+        /**
+         * Sets the bit at index to a value (boolean.)
+         */
+        set(index: number, value: boolean): BitArray;
+
+        /**
+         * Toggles the bit at index. If the bit is on, it is turned off. Likewise, if the bit is off it is turned on.
+         */
+        toggle(index: number): BitArray;
+
+        /**
+         * Returns the value of the bit at index (boolean.)
+         */
+        get(index: number): boolean;
+
+        /**
+         * Resets the BitArray so that it is empty and can be re-used.
+         */
+        reset(): BitArray;
+
+        /**
+         * Returns a copy of this BitArray.
+         */
+        copy(): BitArray;
+
+        /**
+         * Returns true if this BitArray equals another. Two BitArrays are considered
+         * equal if both have the same length and bit pattern.
+         */
+        equals(x: BitArray): boolean;
+
+        /**
+         * Returns the JSON representation of this BitArray.
+         */
+        toJSON(): string;
+
+        /**
+         * Returns a string representation of the BitArray with bits
+         * in mathemetical order.
+         */
+        toBinaryString(): string;
+
+        /**
+         * Returns a hexadecimal string representation of the BitArray
+         * with bits in logical order.
+         */
+        toHexString(): string;
+
+        /**
+         * Returns a string representation of the BitArray with bits
+         * in logical order.
+         */
+        toString(): string;
+
+        /**
+         * Convert the BitArray to an Array of boolean values (slow).
+         */
+        toArray(): boolean[];
+
+        /**
+         * Returns the total number of bits set to one in this BitArray.
+         */
+        count(): number;
+
+        /**
+         * Inverts this BitArray.
+         */
+        not(): BitArray;
+
+        /**
+         * Bitwise OR on the values of this BitArray using BitArray x.
+         */
+        or(x: BitArray): BitArray;
+
+        /**
+         * Bitwise AND on the values of this BitArray using BitArray x.
+         */
+        and(x: BitArray): BitArray;
+
+        /**
+         * Bitwise XOR on the values of this BitArray using BitArray x.
+         */
+        xor(x: BitArray): BitArray;
+    }
+
+    namespace BitArray {}
+    export = BitArray;
+}
\ No newline at end of file