diff --git a/packages/chainspec/src/types.d.ts b/packages/chainspec/src/types.ts
similarity index 94%
rename from packages/chainspec/src/types.d.ts
rename to packages/chainspec/src/types.ts
index f0850b637..a6fa2977c 100644
--- a/packages/chainspec/src/types.d.ts
+++ b/packages/chainspec/src/types.ts
@@ -16,5 +16,5 @@ export type Chainspec = {
     [index: string]: string
   },
   protocolId: null,
-  telemetryUrl: string,
+  telemetryUrl: string
 };
diff --git a/packages/db/src/types.d.ts b/packages/db/src/types.ts
similarity index 96%
rename from packages/db/src/types.d.ts
rename to packages/db/src/types.ts
index e5fc6e3e1..a487a8eab 100644
--- a/packages/db/src/types.d.ts
+++ b/packages/db/src/types.ts
@@ -11,7 +11,7 @@ export type ProgressValue = {
 export type ProgressCb = (progress: ProgressValue) => void;
 
 export type BaseDbOptions = {
-  isCompressed?: boolean,
+  isCompressed?: boolean
 };
 
 export interface BaseDb {
diff --git a/packages/keyring/src/address/types.d.ts b/packages/keyring/src/address/types.ts
similarity index 100%
rename from packages/keyring/src/address/types.d.ts
rename to packages/keyring/src/address/types.ts
diff --git a/packages/keyring/src/pair/types.d.ts b/packages/keyring/src/pair/types.ts
similarity index 100%
rename from packages/keyring/src/pair/types.d.ts
rename to packages/keyring/src/pair/types.ts
diff --git a/packages/keyring/src/types.d.ts b/packages/keyring/src/types.ts
similarity index 66%
rename from packages/keyring/src/types.d.ts
rename to packages/keyring/src/types.ts
index 40c302fce..ca87d62b8 100644
--- a/packages/keyring/src/types.d.ts
+++ b/packages/keyring/src/types.ts
@@ -6,7 +6,7 @@ import { Prefix } from './address/types';
 
 export type KeyringPair$Meta = {
   [index: string]: any
-}
+};
 
 export type KeyringPair$Json = {
   address: string,
@@ -34,25 +34,25 @@ export type KeyringPair = {
 };
 
 export interface KeyringPairs {
-  add: (pair: KeyringPair) => KeyringPair,
-  all: () => Array<KeyringPair>,
-  get: (address: string | Uint8Array) => KeyringPair,
-  remove: (address: string | Uint8Array) => void
+  add: (pair: KeyringPair) => KeyringPair;
+  all: () => Array<KeyringPair>;
+  get: (address: string | Uint8Array) => KeyringPair;
+  remove: (address: string | Uint8Array) => void;
 }
 
 export interface KeyringInstance {
-  decodeAddress (encoded: string | Uint8Array): Uint8Array,
-  encodeAddress (key: Uint8Array | string): string,
-  setAddressPrefix (prefix: Prefix): void,
+  decodeAddress (encoded: string | Uint8Array): Uint8Array;
+  encodeAddress (key: Uint8Array | string): string;
+  setAddressPrefix (prefix: Prefix): void;
 
-  addPair (pair: KeyringPair): KeyringPair,
-  addFromAddress (address: string | Uint8Array, meta?: KeyringPair$Meta): KeyringPair,
-  addFromMnemonic (mnemonic: string, meta?: KeyringPair$Meta): KeyringPair,
-  addFromSeed (seed: Uint8Array, meta?: KeyringPair$Meta): KeyringPair,
-  addFromJson (pair: KeyringPair$Json): KeyringPair,
-  getPair (address: string | Uint8Array): KeyringPair,
-  getPairs (): Array<KeyringPair>,
-  getPublicKeys (): Array<Uint8Array>,
-  removePair (address: string | Uint8Array): void,
-  toJson (address: string | Uint8Array, passphrase?: string): KeyringPair$Json
+  addPair (pair: KeyringPair): KeyringPair;
+  addFromAddress (address: string | Uint8Array, meta?: KeyringPair$Meta): KeyringPair;
+  addFromMnemonic (mnemonic: string, meta?: KeyringPair$Meta): KeyringPair;
+  addFromSeed (seed: Uint8Array, meta?: KeyringPair$Meta): KeyringPair;
+  addFromJson (pair: KeyringPair$Json): KeyringPair;
+  getPair (address: string | Uint8Array): KeyringPair;
+  getPairs (): Array<KeyringPair>;
+  getPublicKeys (): Array<Uint8Array>;
+  removePair (address: string | Uint8Array): void;
+  toJson (address: string | Uint8Array, passphrase?: string): KeyringPair$Json;
 }
diff --git a/packages/trie-codec/src/types.d.ts b/packages/trie-codec/src/types.ts
similarity index 100%
rename from packages/trie-codec/src/types.d.ts
rename to packages/trie-codec/src/types.ts
diff --git a/packages/trie-hash/src/types.d.ts b/packages/trie-hash/src/types.ts
similarity index 100%
rename from packages/trie-hash/src/types.d.ts
rename to packages/trie-hash/src/types.ts
diff --git a/packages/util-crypto/src/types.d.ts b/packages/util-crypto/src/types.ts
similarity index 100%
rename from packages/util-crypto/src/types.d.ts
rename to packages/util-crypto/src/types.ts
diff --git a/packages/util-rlp/src/decoder/types.d.ts b/packages/util-rlp/src/decoder/types.ts
similarity index 99%
rename from packages/util-rlp/src/decoder/types.d.ts
rename to packages/util-rlp/src/decoder/types.ts
index f4995e2cf..699279feb 100644
--- a/packages/util-rlp/src/decoder/types.d.ts
+++ b/packages/util-rlp/src/decoder/types.ts
@@ -5,6 +5,6 @@
 export type DecodeOutput = {
   decoded: Uint8Array | Array<any>,
   remainder: Uint8Array
-}
+};
 
 export type DecodeFunc = (input: Uint8Array) => DecodeOutput;
diff --git a/packages/util-rlp/src/encoder/types.d.ts b/packages/util-rlp/src/encoder/types.ts
similarity index 100%
rename from packages/util-rlp/src/encoder/types.d.ts
rename to packages/util-rlp/src/encoder/types.ts
diff --git a/packages/util/src/compact/types.d.ts b/packages/util/src/compact/types.ts
similarity index 100%
rename from packages/util/src/compact/types.d.ts
rename to packages/util/src/compact/types.ts
diff --git a/packages/util/src/types.d.ts b/packages/util/src/types.ts
similarity index 100%
rename from packages/util/src/types.d.ts
rename to packages/util/src/types.ts