build: switch the dev workflow from npm to pnpm

.github/workflows/stepfunctions.yml

@@ -15,14 +15,17 @@ jobs:
         node-version: [20.x, 24.x, 26.x]
     steps:
       - uses: actions/checkout@v4
+      - name: Install pnpm
+        uses: pnpm/action-setup@v4
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v4
         with:
           node-version: ${{ matrix.node-version }}
-      - run: npm install
-      - run: npm run lint
-      - run: npm test
-      - run: npm run test:smoke
+          cache: pnpm
+      - run: pnpm install --frozen-lockfile
+      - run: pnpm lint
+      - run: pnpm test
+      - run: pnpm test:smoke
       - name: Upload coverage
         uses: codecov/codecov-action@v4
         with:

.husky/pre-commit

@@ -1 +1 @@
-npx lint-staged
+pnpm exec lint-staged

.npmrc

@@ -0,0 +1,3 @@
+# The only peer dependency (serverless) is optional, so don't pull it (and its
+# large tree) into the dev install — matches the lean npm behavior.
+auto-install-peers=false

.prettierignore

@@ -1,3 +1,4 @@
 node_modules
 coverage
 package-lock.json
+pnpm-lock.yaml

README.md

@@ -8,15 +8,18 @@ AWS Step Functions implementation in Node, so you can run your Node.js lambda ha
 ## Installation
 
 ```
-npm i -D stepfunctions
+pnpm add -D stepfunctions
 ```
 
-or if you're using yarn like me:
+or with npm / yarn:
 
 ```
+npm i -D stepfunctions
 yarn add -D stepfunctions
 ```
 
+> This repository itself is developed with [pnpm](https://pnpm.io) (`pnpm install`, `pnpm test`, `pnpm lint`).
+
 ## Motivation
 
 I was working on getting step functions orchestrated using Serverless, Lambda, and Step functions and there was no way to run through the statemachine in Jest. So I made the spec, or parts of it, work in JS so that I can spy and mock the statemachine.