diff --git a/src/contract/HandlerBasedContract.ts b/src/contract/HandlerBasedContract.ts
index 3dd1415..379c0ed 100644
--- a/src/contract/HandlerBasedContract.ts
+++ b/src/contract/HandlerBasedContract.ts
@@ -1,5 +1,4 @@
 import stringify from 'safe-stable-stringify';
-import * as crypto from 'crypto';
 import { SortKeyCacheResult } from '../cache/SortKeyCache';
 import { ContractCallRecord, InteractionCall } from '../core/ContractCallRecord';
 import { ExecutionContext } from '../core/ExecutionContext';
diff --git a/src/contract/deploy/DataItem.ts b/src/contract/deploy/DataItem.ts
index 617d2be..e69de29 100644
--- a/src/contract/deploy/DataItem.ts
+++ b/src/contract/deploy/DataItem.ts
@@ -1,36 +0,0 @@
-export declare abstract class Signer {
-  readonly publicKey: Buffer;
-  readonly signatureType: number;
-  readonly signatureLength: number;
-  readonly ownerLength: number;
-  readonly pem?: string | Buffer;
-  abstract sign(message: Uint8Array): Promise<Uint8Array> | Uint8Array;
-  static verify(_: string | Buffer): boolean;
-}
-
-type ResolvesTo<T> = T | Promise<T> | ((...args: any[]) => Promise<T>);
-
-export abstract class DataItem {
-  readonly id: string;
-  readonly signatureType: ResolvesTo<number>;
-  readonly rawSignature: ResolvesTo<Buffer>;
-  readonly signature: ResolvesTo<string>;
-  readonly signatureLength: ResolvesTo<number>;
-  readonly rawOwner: ResolvesTo<Buffer>;
-  readonly owner: ResolvesTo<string>;
-  readonly ownerLength: ResolvesTo<number>;
-  readonly rawTarget: ResolvesTo<Buffer>;
-  readonly target: ResolvesTo<string>;
-  readonly rawAnchor: ResolvesTo<Buffer>;
-  readonly anchor: ResolvesTo<string>;
-  readonly rawTags: ResolvesTo<Buffer>;
-  readonly tags: ResolvesTo<{ name: string; value: string }[]>;
-  readonly rawData: ResolvesTo<Buffer>;
-  readonly data: ResolvesTo<string>;
-  abstract sign(signer: Signer): Promise<Buffer>;
-  abstract isValid(): Promise<boolean>;
-  static async verify(..._: any[]): Promise<boolean> {
-    throw new Error('You must implement `verify`');
-  }
-  abstract getRaw(): Buffer;
-}