mika
Posted 5d ago

Senior Full Stack Developer React/FastAPI/Django (Frontend-Affinity) (m/f/d)

mika
Berlin, Berlin, Germany
HybridFull Time
Responsibilities
  • improving frontend
  • building features
  • extending backend
Requirements
  • Professional software development experience
  • Expert React skills
  • Python/FastAPI backend experience
  • AI-assisted engineering experience
  • Systems thinking, and English fluency
  • German is a bonus
Technical tools mentioned
FastAPIDjangoReactMaterial UIreact-queryPostgreSQLAWSClaude CodeCursorCodexGitHub Copilot

Job description

mika is revolutionizing financial management for small businesses with an AI-powered platform that combines automated accounting, proactive insights, and conversational AI. We're on a mission to make expert financial navigation and compliance accessible to every small business owner – dramatically reducing costs and bureaucratic burden. We're a small, senior team shipping fast, and every line of code we ship matters.

Our stack: FastAPI & Django backend, React frontend (Material UI, react-query), PostgreSQL, AWS. We build agentic AI systems that do real accounting work.

Tasks

We need a Senior Full-Stack Developer who leans frontend – someone who makes our product look and feel as good as it works under the hood.

You'll own features end-to-end. That means you think through the entire user flow, edge cases, error states, and architecture before you start building. You work with high autonomy and take real ownership – we trust you to make good decisions and deliver clean solutions.

Concretely, you'll:

  • Drive frontend improvements – not just fixing bugs but proactively elevating UX and visual quality on a regular cadence
  • Build and own complex full-stack features in our accounting platform
  • Use Claude Code, Cursor, or similar AI engineering tools as your primary development workflow – we are a senior team where everyone writes high-quality code at a high pace, and this is only possible through the use of the latest coding tools. You'll get access to all the subscriptions you need to work efficiently
  • Adapt and extend our Python/FastAPI & Django backend where needed (CRUD-level changes and beyond)
  • Contribute to code quality and architecture decisions in a small senior team

Requirements

  • Professional experience in software development with a proven track record of owning and delivering complex projects.
  • Expertise in React to build high-quality, accessible, and production-ready user interfaces.
  • A sharp eye for design that ensures layouts and components are implemented with pixel-perfect accuracy.
  • Hands-on skill with AI-assisted engineering using tools like Cursor, Claude Code, Codex, or GitHub Copilot. You have already built real things with those tools.
  • The ability to work across the stack by independently navigating and extending a Python/FastAPI backend.
  • A systems-thinking mindset to map out full features, edge cases, and failure modes before writing any code.
  • Fluency in English, while any knowledge of German is a welcome bonus.

Nice to have:

  • Background in agentic AI systems or LLM-powered products.
  • Familiarity with B2B fintech, PostgreSQL, or German accounting standards like DATEV.

Benefits

  • A small team of strong, senior engineers who respect each other's time.
  • Real autonomy and ownership from day one.
  • Work that's genuinely hard and interesting – German tax law + AI agents is not a solved problem.
  • Competitive salary and a product that's actually used by real customers daily.
  • Almost no meetings – on average 95% focus time per day.
  • 100% Remote option, option to work abroad and no minimum required office attendence.
  • Fully flexible working hours apart from Daily Standup.
  • Berlin location preferred but remote possible.

We welcome applications from people of all backgrounds, genders, and identities.

About mika

Berlin-based private fintech startup providing AI-assisted bookkeeping, VAT filing, and tax services for small businesses.

Year founded
2022
Employees
29
Organization type
Private
Latest investment
Raised $893.00k Pre-Seed (2024) — led by Samen Slimmer Alliance
Headquarters
DE

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