diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..f781726
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,97 @@
+declare module 'nsrestlet' {
+
+  interface BasicSettings {
+    /**
+     * You NetSuite Account ID. Also known as realm
+     */
+    accountId: number | string
+  }
+
+  /**
+   * OAuth requires `accountId`, a `Consumer Key-Secret Pair` (Found on the Integrations page in Netsuite), and a `Token Key-Secret Pair` (Found on the Tokens page in Netsuite).
+   */
+  interface OAuthSettings extends BasicSettings {
+    tokenKey: string,
+    tokenSecret: string,
+    consumerKey: string,
+    consumerSecret: string,
+  }
+
+  /**
+   * NLAuth requires an `email` and `password`. It also allows us to 
+   * specifiy a `role`, which isn't required but is highly reccomended.
+   */
+  interface NLAuthSettings extends BasicSettings {
+    email: string,
+    password: string,
+
+    /**
+     * Recommended.
+     */
+    role?: number | string,
+  }
+
+  /**
+   * If a retryable error occurs and `backoff` and `retries` properties
+   * are provided, it will keep requesting until a successful resolution 
+   * or the provided limits are reached. Otherwise, an error is returned 
+   * instead.
+   * 
+   * Retryable errors:
+   * - `ECONNRESET`
+   * - `ESOCKETTIMEDOUT`
+   * - `ETIMEDOUT`
+   * - `SSS_REQUEST_LIMIT_EXCEEDED`
+   */
+  interface ErrorRetryURLSettings {
+    /**
+     * The amount of time, in milliseconds, to exponentially backoff on 
+     * each retry.
+     */
+    backoff?: number,
+
+    /**
+     * The number of times to retry the request if an error is returned.
+     */
+    retries?: number,
+  }
+
+  interface DeriveURLSettings extends ErrorRetryURLSettings {
+    /**
+     * Script Id
+     */
+    script: number | string,
+
+    /**
+     * Deployment Id
+     */
+    deployment: number | string
+  }
+
+  interface URLSettings extends ErrorRetryURLSettings {
+    /**
+     * Valid URL Like:
+     * > https://**accountId**.restlets.api.netsuite.com/app/site/hosting/restlet.nl?script=**scriptId**&deploy=**deploymentId**
+     */
+    url: string
+  }
+
+  interface HTTPFacade {
+    get(payload: any, callback: (error: any, response: any) => void): void,
+    get(payload: any): Promise<any>,
+
+    post(payload: any, callback: (error: any, response: any) => void): void,
+    post(payload: any): Promise<any>,
+
+    put(payload: any, callback: (error: any, response: any) => void): void,
+    put(payload: any): Promise<any>,
+
+    delete(payload: any, callback: (error: any, response: any) => void): void,
+    delete(payload: any): Promise<any>,
+  }
+
+  function createLink(
+    accountSettings: OAuthSettings | NLAuthSettings,
+    urlSettings: URLSettings | DeriveURLSettings
+  ): HTTPFacade;
+}