Back to portfolioCase study · 07
Fintech educationStartup · Vienna

Learn to invest, like a game.

Courses by professors and investors, in a playful app.

Fingu teaches beginners how to invest through short videos and quizzes. As Head of Engineering I owned the API, the data model and payments, and built across every app.

ROLE
Head of Engineering (hands-on)
WHEN
Mar 2022 – Aug 2023
WHERE
Vienna, Austria (remote)
MARKETS
German and English

THE HEADLINE

1 API, 3 apps

One GraphQL backend behind the learner app, the website and the content studio

~50%
of all commits were mine
29
backend modules
2
languages from day one

01 · The problem

Investing is taught like a textbook.

People who want to start investing face jargon, long courses and advice they can’t trust. Fingu set out to make it short, expert-made and fun, for €4.99 a month.

02 · What I built

A learning platform, start to finish.

01

Courses and lessons

Courses, chapters and lessons with video, quizzes and a glossary.

VideoQuizzes
02

Progress and streaks

Progress at every level and daily learning streaks to keep people coming back.

Gamification
03

Experts and articles

Expert profiles linked to their courses and articles, plus an Investors Club.

Content
04

Subscriptions

Monthly plans, coupons and webhooks that unlock access when an invoice is paid.

Stripe
05

Content studio

An internal dashboard where the team builds courses with drag and drop and rich text.

Admin
06

Sign in your way

Email, Google or Facebook, with role-based permissions behind it.

OAuthCASL

03 · Key decisions

One source of truth.

01

One GraphQL API for everything

The learner app, the marketing site and the content studio all read from the same code-first API, so content is written once.

02

Rebuild the learner app on generated types

In 2023 we rebuilt the learner app with GraphQL codegen and Playwright tests, so the frontend could move faster without breaking.

04 · Stack

Under the hood.

Backend

  • NestJS
  • GraphQL
  • TypeORM
  • PostgreSQL
  • Passport

Frontend

  • Next.js
  • React
  • Chakra UI
  • Apollo Client
  • Framer Motion

Services

  • Stripe
  • AWS S3
  • SendGrid
  • Mailchimp
  • Docker

05 · Results

What it added up to.

~1,900
Commits across five repos in 17 months
39
Data entities in the learning model
2
Markets: German and English

Next case study · 08

Replatforming e-commerce

Building a learning or fintech product?

I lead engineering hands-on, from the data model to the app.