diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..60c570f
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,88 @@
+// Type definitions for readline-sync 1.4
+// Project: https://github.com/anseki/readline-sync
+// Definitions by: Tristan Jones <https://github.com/jonestristand>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+export type OptionType = string | number | RegExp | ((input: string) => boolean);
+
+export interface BasicOptions {
+    prompt?: any;
+    hideEchoBack?: boolean | undefined;
+    mask?: string | undefined;
+    limit?: OptionType | OptionType[] | undefined;
+    limitMessage?: string | undefined;
+    defaultInput?: string | undefined;
+    trueValue?: OptionType | OptionType[] | undefined;
+    falseValue?: OptionType | OptionType[] | undefined;
+    caseSensitive?: boolean | undefined;
+    keepWhitespace?: boolean | undefined;
+    encoding?: string | undefined;
+    bufferSize?: number | undefined;
+    print?(display: string, encoding: string): void;
+    history?: boolean | undefined;
+    cd?: boolean | undefined;
+    charlist?: string | undefined;
+    min?: any;
+    max?: any;
+    confirmMessage?: any;
+    unmatchMessage?: any;
+    exists?: any;
+    isFile?: boolean | undefined;
+    isDirectory?: boolean | undefined;
+    validate?(path: string): boolean | string;
+    create?: boolean | undefined;
+    guide?: boolean | undefined;
+    cancel?: any;
+}
+
+// Basic Functions
+export function question(query?: any, options?: BasicOptions): string;
+export function prompt(options?: BasicOptions): string;
+export function keyIn(query?: any, options?: BasicOptions): string;
+export function setDefaultOptions(options?: BasicOptions): BasicOptions;
+
+// Utility Functions
+export function questionEMail(query?: any, options?: BasicOptions): string;
+export function questionNewPassword(query?: any, options?: BasicOptions): string;
+export function questionInt(query?: any, options?: BasicOptions): number;
+export function questionFloat(query?: any, options?: BasicOptions): number;
+export function questionPath(query?: any, options?: BasicOptions): string;
+
+export function promptCL(commandHandler?: { [id: string]: (...args: string[]) => void } | ((command: string, ...args: string[]) => void), options?: BasicOptions): string[];
+export function promptLoop(inputHandler: (value: string) => boolean, options?: BasicOptions): void;
+export function promptCLLoop(commandHandler?: { [id: string]: (...args: string[]) => boolean | void } | ((command: string, ...args: string[]) => boolean | void), options?: BasicOptions): void;
+export function promptSimShell(options?: BasicOptions): string;
+
+export function keyInYN(query?: any, options?: BasicOptions): boolean | string;
+export function keyInYNStrict(query?: any, options?: BasicOptions): boolean;
+export function keyInPause(query?: any, options?: BasicOptions): void;
+export function keyInSelect(items: string[], query?: any, options?: BasicOptions): number;
+
+export function getRawInput(): string;
+
+// Deprecated
+
+/**
+ * @deprecated Use the bufferSize option instead: readlineSync.setDefaultOptions({bufferSize: value});
+ */
+export function setBufferSize(value: number): void;
+
+/**
+ * @deprecated Use the encoding option instead: readlineSync.setDefaultOptions({encoding: value});
+ */
+export function setEncoding(value: string): void;
+
+/**
+ * @deprecated Use the mask option instead: readlineSync.setDefaultOptions({mask: value});
+ */
+export function setMask(value: string): void;
+
+/**
+ * @deprecated Use the print option instead: readlineSync.setDefaultOptions({print: value});
+ */
+export function setPrint(value: (display: string, encoding: string) => void): void;
+
+/**
+ * @deprecated Use the prompt option instead: readlineSync.setDefaultOptions({prompt: value});
+ */
+export function setPrompt(value: any): void;
\ No newline at end of file
diff --git a/package.json b/package.json
index 476f8c2..ff7d73f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@thundernetworkrad/readline-sync",
-  "version": "2023.01.10",
+  "version": "2023.01.26",
   "title": "readlineSync",
   "description": "Synchronous Readline for interactively running to have a conversation with the user via a console(TTY).",
   "keywords": [
diff --git a/tslint.json b/tslint.json
new file mode 100644
index 0000000..89bfe2f
--- /dev/null
+++ b/tslint.json
@@ -0,0 +1 @@
+{ "extends": "@definitelytyped/dtslint/dt.json" }
\ No newline at end of file