diff --git a/.github/workflows/prv.yml b/.github/workflows/prv.yml
index 87dd9c2..52e1281 100644
--- a/.github/workflows/prv.yml
+++ b/.github/workflows/prv.yml
@@ -18,5 +18,6 @@ jobs:
       - uses: DeterminateSystems/nix-installer-action@c5a866b6ab867e88becbed4467b93592bce69f8a # v21
       - run: nix run github:nicknovitski/nix-develop .#workflow
 
+      - run: biome ci
       - run: ./node_modules/.bin/tsc --build tsconfig.json
       - run: node --test
diff --git a/base58/index.test.js b/base58/index.test.js
index 7473af8..7a7aaae 100644
--- a/base58/index.test.js
+++ b/base58/index.test.js
@@ -1,5 +1,5 @@
-import { test } from "node:test";
 import assert from "node:assert/strict";
+import { test } from "node:test";
 import * as fc from "fast-check";
 import { decode, encode } from "./index.js";
 
@@ -39,7 +39,7 @@ const hexTestVectors = [
   ],
 ];
 
-test("base58: encode", (t) => {
+test("base58: encode", () => {
   for (const [string, expected] of stringTestVectors) {
     const input = new TextEncoder().encode(string);
     assert.equal(encode(input), expected, string);
@@ -53,7 +53,7 @@ test("base58: encode", (t) => {
   }
 });
 
-test("base58: decode", (t) => {
+test("base58: decode", () => {
   for (const [expected, input] of stringTestVectors) {
     const string = new TextDecoder().decode(decode(input));
     assert.equal(string, expected, input);
@@ -67,7 +67,7 @@ test("base58: decode", (t) => {
   }
 });
 
-test("base58: roundtrip (decode . encode === id)", (t) => {
+test("base58: roundtrip (decode . encode === id)", () => {
   function roundtrip(bs) {
     assert.deepEqual(new Uint8Array(bs), decode(encode(bs)));
   }
@@ -80,7 +80,7 @@ test("base58: roundtrip (decode . encode === id)", (t) => {
   fc.assert(fc.property(fc.array(fc.constant(0xff)), roundtrip));
 });
 
-test("base58: roundtrip (encode . decode === id)", (t) => {
+test("base58: roundtrip (encode . decode === id)", () => {
   const alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
   const arbInput = fc.string({ unit: fc.constantFrom(...alphabet.split("")) });
 
diff --git a/base58/index.ts b/base58/index.ts
index 0a1914c..8093ce2 100644
--- a/base58/index.ts
+++ b/base58/index.ts
@@ -1,6 +1,6 @@
 const bytesToHex = (() => {
   const s = Array.from({ length: 256 }).map((_, i) =>
-    i.toString(16).padStart(2, "0")
+    i.toString(16).padStart(2, "0"),
   );
   return (uint8a: Uint8Array) => [...uint8a].map((o) => s[o]).join("");
 })();
@@ -13,7 +13,7 @@ export function encode(input: Uint8Array): string {
   }
 
   // Uint8Array -> BigInt (Big Endian)
-  let x = BigInt("0x" + bytesToHex(input));
+  let x = BigInt(`0x${bytesToHex(input)}`);
 
   const output = [];
   while (x > 0n) {
@@ -40,7 +40,7 @@ export function decode(output: string): Uint8Array {
     const value = letters.indexOf(char);
     if (value === undefined) {
       throw new Error(
-        `base58.decode received invalid input. Character '${char}' is not in the base58 alphabet.`
+        `base58.decode received invalid input. Character '${char}' is not in the base58 alphabet.`,
       );
     }
     for (let j = 0; j < bytes.length; j++) {
diff --git a/biome.json b/biome.json
new file mode 100644
index 0000000..12a54f1
--- /dev/null
+++ b/biome.json
@@ -0,0 +1,11 @@
+{
+  "$schema": "https://biomejs.dev/schemas/2.3.11/schema.json",
+
+  "files": {
+    "includes": ["**", "!**/.direnv", "!**/node_modules"]
+  },
+
+  "formatter": {
+    "indentStyle": "space"
+  }
+}
diff --git a/flake.nix b/flake.nix
index 0ebed5c..0834eb8 100644
--- a/flake.nix
+++ b/flake.nix
@@ -16,6 +16,7 @@
             buildInputs = [
               pkgs.nodejs
               pkgs.pnpm
+              pkgs.biome
             ];
           };
 
@@ -23,6 +24,7 @@
             buildInputs = [
               pkgs.nodejs
               pkgs.pnpm
+              pkgs.biome
             ];
 
             shellHook = ''