diff --git a/src/blst/index.ts b/src/blst/index.ts
index 380f1d7..49d9bbf 100644
--- a/src/blst/index.ts
+++ b/src/blst/index.ts
@@ -8,10 +8,10 @@ export * from "../constants";
 
 export {Keypair, PrivateKey, PublicKey, Signature};
 
-export async function initBLS() {
+export async function initBLS(): Promise<void> {
   // Native bindings require no init() call
 }
-export function destroy() {
+export function destroy(): void {
   // Native bindings require no destroy() call
 }
 
diff --git a/src/blst/signature.ts b/src/blst/signature.ts
index 508fedf..eed4ded 100644
--- a/src/blst/signature.ts
+++ b/src/blst/signature.ts
@@ -42,6 +42,14 @@ export class Signature {
     );
   }
 
+  toBytes(): Buffer {
+    return Buffer.from(this.affine.toBytes());
+  }
+
+  toHex(): string {
+    return bytesToHex(this.toBytes());
+  }
+
   private aggregateVerify(msgs: Uint8Array[], pks: blst.PublicKey[]): boolean {
     // If this set is simply an infinity signature and infinity pubkey then skip verification.
     // This has the effect of always declaring that this sig/pubkey combination is valid.
@@ -52,12 +60,4 @@ export class Signature {
 
     return blst.aggregateVerify(msgs, pks, this.affine);
   }
-
-  toBytes(): Buffer {
-    return Buffer.from(this.affine.toBytes());
-  }
-
-  toHex(): string {
-    return bytesToHex(this.toBytes());
-  }
 }
diff --git a/src/herumi/index.ts b/src/herumi/index.ts
index c4de6f8..4ee3138 100644
--- a/src/herumi/index.ts
+++ b/src/herumi/index.ts
@@ -3,7 +3,6 @@ import {PrivateKey} from "./privateKey";
 import {PublicKey} from "./publicKey";
 import {Signature} from "./signature";
 import {initBLS, destroy} from "./context";
-import {PUBLIC_KEY_LENGTH} from "../constants";
 import assert from "assert";
 import {toBuffer} from "../helpers/utils";
 
diff --git a/test/benchmark/runner.ts b/test/benchmark/runner.ts
index 19f06fa..6b28931 100644
--- a/test/benchmark/runner.ts
+++ b/test/benchmark/runner.ts
@@ -8,7 +8,7 @@ export function runBenchmark<T, R>({
   testRunner: (input: T) => R;
   runs?: number;
   id: string;
-}) {
+}): void {
   const diffsNanoSec: bigint[] = [];
 
   for (let i = 0; i < runs; i++) {
diff --git a/test/switch.ts b/test/switch.ts
index 06ce9c6..19765bb 100644
--- a/test/switch.ts
+++ b/test/switch.ts
@@ -4,6 +4,7 @@ import herumi from "../src/herumi";
 export type Implementation = "blst" | "herumi";
 export const implementations: Implementation[] = ["blst", "herumi"];
 
+// eslint-disable-next-line @typescript-eslint/explicit-function-return-type
 export function getBls(implementation: Implementation) {
   switch (implementation) {
     case "blst":
diff --git a/test/unit/index.test.ts b/test/unit/index.test.ts
index 0733edc..4001b82 100644
--- a/test/unit/index.test.ts
+++ b/test/unit/index.test.ts
@@ -1,16 +1,9 @@
 import {expect} from "chai";
 import {forEachImplementation} from "../switch";
-import {getRandomBytes} from "../../src/helpers/utils";
-
-function randomMessage(): Uint8Array {
-  return getRandomBytes(32);
-}
-
-function getN<T>(n: number, getter: () => T): T[] {
-  return Array.from({length: n}, () => getter());
-}
+import {getN, randomMessage} from "../util";
 
 forEachImplementation((bls) => {
+  // eslint-disable-next-line @typescript-eslint/explicit-function-return-type
   function getRandomData() {
     const sk = bls.PrivateKey.fromKeygen();
     const pk = sk.toPublicKey();
@@ -53,7 +46,7 @@ forEachImplementation((bls) => {
   });
 
   describe("verify multiple", () => {
-    it(`should verify aggregated signatures`, () => {
+    it("should verify aggregated signatures", () => {
       const sks = getN(4, () => bls.PrivateKey.fromKeygen());
       const msgs = getN(2, () => randomMessage());
       const pks = sks.map((sk) => sk.toPublicKey());
diff --git a/test/util.ts b/test/util.ts
index 50478de..2a97bf4 100644
--- a/test/util.ts
+++ b/test/util.ts
@@ -1,3 +1,5 @@
+import {getRandomBytes} from "../src/helpers/utils";
+
 export function fromHexString(hex: string): Buffer {
   return Buffer.from(hex.replace("0x", ""), "hex");
 }
@@ -5,3 +7,11 @@ export function fromHexString(hex: string): Buffer {
 export function toHexString(bytes: Buffer | Uint8Array): string {
   return `0x${Buffer.from(bytes).toString("hex")}`;
 }
+
+export function randomMessage(): Uint8Array {
+  return getRandomBytes(32);
+}
+
+export function getN<T>(n: number, getter: () => T): T[] {
+  return Array.from({length: n}, () => getter());
+}