diff --git a/packages/did/src/did/details.ts b/packages/did/src/did/details.ts
index 213cafe..c370cd2 100644
--- a/packages/did/src/did/details.ts
+++ b/packages/did/src/did/details.ts
@@ -15,6 +15,7 @@ import type { DidKeys, IDidDetails, KeyRelationship, SignedData } from '../types
 import { assert } from '@polkadot/util';
 
 import { base58Encode } from '@zcloak/crypto';
+import { parseDid } from '@zcloak/did-resolver/parseDid';
 
 import { DidKeyring } from './keyring';
 
@@ -34,6 +35,7 @@ export function typeTransform(type: KeypairType): VerificationMethodType {
 
 export abstract class DidDetails extends DidKeyring implements IDidDetails {
   public id: DidUrl;
+  public identifier: string;
   public controller: Set<DidUrl>;
   public keyRelationship: Map<DidUrl, KeyRelationship>;
   public authentication?: Set<DidUrl>;
@@ -56,6 +58,7 @@ export abstract class DidDetails extends DidKeyring implements IDidDetails {
   }: IDidDetails) {
     super();
     this.id = id;
+    this.identifier = parseDid(id).identifier;
     this.controller = controller;
     this.keyRelationship = keyRelationship;
     this.authentication = authentication;
diff --git a/packages/did/src/index.ts b/packages/did/src/index.ts
index 3ddacdf..025b0d7 100644
--- a/packages/did/src/index.ts
+++ b/packages/did/src/index.ts
@@ -4,4 +4,6 @@
 export * from './did';
 export * as helpers from './did/helpers';
 
+export * as keys from './keys';
+
 export * from './hasher';
diff --git a/packages/did/src/keys/backup.spec.ts b/packages/did/src/keys/backup.spec.ts
new file mode 100644
index 0000000..68778c8
--- /dev/null
+++ b/packages/did/src/keys/backup.spec.ts
@@ -0,0 +1,37 @@
+// Copyright 2021-2022 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import { generateMnemonic } from '@zcloak/crypto';
+import { Keyring } from '@zcloak/keyring';
+
+import { createEcdsaFromMnemonic } from '../did/helpers';
+import { backup, getEcdsaIdentifierPair } from './backup';
+import { DEFAULT_DID_KEYS_JSON_VERSION } from './defaults';
+
+describe('Backup did', (): void => {
+  const keyring = new Keyring();
+
+  it('get ecdsa identifier pair', () => {
+    const mnemonic = generateMnemonic(12);
+    const did = createEcdsaFromMnemonic(mnemonic, keyring);
+
+    expect(getEcdsaIdentifierPair(keyring, did)?.publicKey).toEqual(
+      keyring.createFromMnemonic(mnemonic, undefined, 'ecdsa').publicKey
+    );
+  });
+
+  it('backup did', () => {
+    const mnemonic = generateMnemonic(12);
+    const did = createEcdsaFromMnemonic(mnemonic, keyring);
+
+    expect(backup(keyring, did, '1234')).toMatchObject({
+      didUrl: did.id,
+      version: DEFAULT_DID_KEYS_JSON_VERSION,
+      authentication: Array.from(did.authentication ?? []),
+      assertionMethod: Array.from(did.assertionMethod ?? []),
+      keyAgreement: Array.from(did.keyAgreement ?? []),
+      capabilityInvocation: Array.from(did.capabilityInvocation ?? []),
+      capabilityDelegation: Array.from(did.capabilityDelegation ?? [])
+    });
+  });
+});
diff --git a/packages/did/src/keys/backup.ts b/packages/did/src/keys/backup.ts
new file mode 100644
index 0000000..f4f2fd4
--- /dev/null
+++ b/packages/did/src/keys/backup.ts
@@ -0,0 +1,43 @@
+// Copyright 2021-2022 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import type { KeyringPair } from '@zcloak/keyring/types';
+import type { Did } from '../did';
+import type { DidKeys$Json } from './types';
+
+import { assert } from '@polkadot/util';
+
+import { ethereumEncode } from '@zcloak/crypto';
+import { Keyring } from '@zcloak/keyring';
+
+import { DEFAULT_DID_KEYS_JSON_VERSION } from './defaults';
+
+export function getEcdsaIdentifierPair(keyring: Keyring, did: Did): KeyringPair | undefined {
+  const identifierPair = keyring
+    .getPairs()
+    .find((pair) => ethereumEncode(pair.publicKey) === did.identifier);
+
+  return identifierPair;
+}
+
+export function backup(keyring: Keyring, did: Did, password: string): DidKeys$Json {
+  const identifierPair = getEcdsaIdentifierPair(keyring, did);
+
+  assert(identifierPair, 'no identifier pair found');
+
+  return {
+    didUrl: did.id,
+    version: DEFAULT_DID_KEYS_JSON_VERSION,
+    identifierKey: identifierPair.toJson(password),
+    keys: Array.from(did.keyRelationship.values()).map(({ publicKey }) => {
+      const pair = did.getPair(publicKey);
+
+      return pair.toJson(password);
+    }),
+    authentication: Array.from(did.authentication ?? []),
+    assertionMethod: Array.from(did.assertionMethod ?? []),
+    keyAgreement: Array.from(did.keyAgreement ?? []),
+    capabilityInvocation: Array.from(did.capabilityInvocation ?? []),
+    capabilityDelegation: Array.from(did.capabilityDelegation ?? [])
+  };
+}
diff --git a/packages/did/src/keys/defaults.ts b/packages/did/src/keys/defaults.ts
new file mode 100644
index 0000000..901bda1
--- /dev/null
+++ b/packages/did/src/keys/defaults.ts
@@ -0,0 +1,6 @@
+// Copyright 2021-2022 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import { DidKeys$JsonVersion } from './types';
+
+export const DEFAULT_DID_KEYS_JSON_VERSION: DidKeys$JsonVersion = '1';
diff --git a/packages/did/src/keys/index.ts b/packages/did/src/keys/index.ts
new file mode 100644
index 0000000..d19c96f
--- /dev/null
+++ b/packages/did/src/keys/index.ts
@@ -0,0 +1,5 @@
+// Copyright 2021-2022 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+export * from './backup';
+export * from './restore';
diff --git a/packages/did/src/keys/restore.spec.ts b/packages/did/src/keys/restore.spec.ts
new file mode 100644
index 0000000..65ea92d
--- /dev/null
+++ b/packages/did/src/keys/restore.spec.ts
@@ -0,0 +1,22 @@
+// Copyright 2021-2022 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import { generateMnemonic } from '@zcloak/crypto';
+import { Keyring } from '@zcloak/keyring';
+
+import { createEcdsaFromMnemonic } from '../did/helpers';
+import { backup } from './backup';
+import { restore } from './restore';
+
+describe('Restore did', (): void => {
+  const keyring = new Keyring();
+
+  it('backup did and restore', () => {
+    const mnemonic = generateMnemonic(12);
+    const did = createEcdsaFromMnemonic(mnemonic, keyring);
+
+    const json = backup(keyring, did, '1234');
+
+    expect(restore(keyring, json, '1234')).toMatchObject(did);
+  });
+});
diff --git a/packages/did/src/keys/restore.ts b/packages/did/src/keys/restore.ts
new file mode 100644
index 0000000..16fcabd
--- /dev/null
+++ b/packages/did/src/keys/restore.ts
@@ -0,0 +1,47 @@
+// Copyright 2021-2022 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import type { DidUrl } from '@zcloak/did-resolver/types';
+import type { Keyring } from '@zcloak/keyring';
+import type { DidKeys$Json } from './types';
+
+import { Did } from '../did';
+import { create } from '../did/helpers';
+import { IDidDetails, KeyRelationship } from '../types';
+
+export function restore(keyring: Keyring, json: DidKeys$Json, password: string): Did {
+  const keyRelationship = new Map<DidUrl, KeyRelationship>();
+
+  json.keys.forEach((key, index) => {
+    const pair = keyring.addFromJson(key);
+
+    pair.unlock(password);
+
+    const id: DidUrl = `${json.didUrl}#key-${index}`;
+    const controller: DidUrl[] = [`${json.didUrl}`];
+    const publicKey = pair.publicKey;
+
+    keyRelationship.set(id, {
+      id,
+      controller,
+      publicKey
+    });
+  });
+  const pair = keyring.addFromJson(json.identifierKey);
+
+  pair.unlock(password);
+
+  const details: IDidDetails = {
+    id: json.didUrl,
+    controller: new Set([json.didUrl]),
+    keyRelationship,
+    authentication: new Set(json.authentication),
+    assertionMethod: new Set(json.assertionMethod),
+    keyAgreement: new Set(json.keyAgreement),
+    capabilityInvocation: new Set(json.capabilityInvocation),
+    capabilityDelegation: new Set(json.capabilityDelegation),
+    service: new Map()
+  };
+
+  return create(details, keyring);
+}
diff --git a/packages/did/src/keys/types.ts b/packages/did/src/keys/types.ts
new file mode 100644
index 0000000..4f16e62
--- /dev/null
+++ b/packages/did/src/keys/types.ts
@@ -0,0 +1,19 @@
+// Copyright 2021-2022 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import type { DidUrl } from '@zcloak/did-resolver/types';
+import type { KeyringPair$Json } from '@zcloak/keyring/types';
+
+export type DidKeys$JsonVersion = '1';
+
+export interface DidKeys$Json {
+  didUrl: DidUrl;
+  version: DidKeys$JsonVersion;
+  identifierKey: KeyringPair$Json;
+  keys: KeyringPair$Json[];
+  authentication: DidUrl[];
+  assertionMethod: DidUrl[];
+  keyAgreement: DidUrl[];
+  capabilityInvocation: DidUrl[];
+  capabilityDelegation: DidUrl[];
+}
diff --git a/tsconfig.eslint.json b/tsconfig.eslint.json
index 364e6f3..c6987c5 100644
--- a/tsconfig.eslint.json
+++ b/tsconfig.eslint.json
@@ -1,15 +1,11 @@
 {
   "extends": "./tsconfig.base.json",
+  "exclude": [
+    "build/**/*",
+    "**/build/**/*"
+  ],
   "compilerOptions": {
     "baseUrl": "./packages",
     "composite": false
-  },
-  "include": [
-    "packages/**/src/**/*",
-    "packages/**/scripts/**/*",
-    "packages/**/test/**/*"
-  ],
-  "exclude": [
-    "**/node_modules/**/*"
-  ]
+  }
 }