Full Stack Engineer

Direct message the job poster from FLIZpay

We're seeking a motivated person with high agency who is ready to make a big impact at our startup. This is a chance to take ownership of key projects, and be a driving force in shaping our company's future from the ground up. If you have a strong work ethic and a passion for turning ideas into reality, then this is the opportunity for you.

You Have:

- 5+ years of experience

- High agency and motivation to work hard and long

- Experience delivering high-quality mobile or web applications.

- Good understanding of backend technologies and database principles.

- Skill in integrating RESTful APIs and third-party services.

- Expertise in frontend technologies like React and React Native.

- Excellent communication skills, thriving in teamwork or independently leading projects.

Nice to Have:

- A passion for product management and design.

- Knowledge of MERN stack.

- Startup or scale-up experience, especially in the finance sector.

Why Fliz?

At Fliz, we're revolutionizing mobile payments to be instant, fee-free, and rewarding for everyone. We're on a quest to make Fliz the go-to payment method, where companies enjoy free transactions and payers benefit from cashback on their purchases. Be part of a vibrant team led by Roberto, a seasoned full-stack developer and fintech co-founder, and Konrad, with a decade in financial services, as we redefine the payment landscape from our Berlin base.

Start immediately with a competitive salary and equity package, in a role where your contributions are integral to our shared success.

We already have 400+ companies and over 8000 users.

Test Task:

We only want highly motivated people, and for that we require a small test task. Feel free to use AI.

FLIZpay— Mini‑Checkout Challenge

We’d like you to spendone focused afternoon (Aim for 4 to 6 hours)— building a proof‑of‑concept that shows how you approach problems and structure code.

The scenario.Picture a single merchant behind the counter. They open a dashboard, enter an amount (say, “€2.50 for a cappuccino”), pressCreaterequest,which creates a QRC with the data. When the customer scans that QRC they see the amount, tapPaynow on their screen, and the request flips topaidwith a friendly success message.

Recommended architecture

• Merchant front-end (React):cash-register UI to create and monitor requests.
• Merchant back-end (Node/Express + Mongo):stores requests andlistensfor payment-status webhooks.
• FLIZpay back-end (Node/Express stub):pretend PSP that exposes “create payment”, “get status”, andsendswebhooks when a payment changes state.
• Payer mini-app (React web or Expo React Native):lets the customer scan the QR and pressPay now.

What matters

• No authentication— keep it lean.
• Express + Mongoonly; Mongoose optional.
• docker compose up must spin upbothback-ends,bothfront-ends (dev servers are fine), and Mongo.
• Show the status flip in real time (WebSocket, SSE, or polling — your choice).

What to hand in.

A public repo (or zip) containing the code, a short README telling us how to run it and outlining any assumptions, plus a few screenshots or a tiny screen‑capture that proves the flow works end‑to‑end.

Seniority level

• Seniority level

  Mid-Senior level

Employment type

• Employment type

  Part-time

Job function

• Job function

  Engineering and Information Technology

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