Senior Full Stack Developer (Equity Only | Remote | Flutter + FastAPI)

JR United Kingdom; Ashton-under-Lyne; Remote; GBP 50,000 - 80,000; Part time

Job summary

A leading company in the tech startup space is seeking a Senior Full Stack Developer for an equity-only role. This position involves leading the development of a unique platform that leverages AI and community engagement. The ideal candidate will have extensive experience in Flutter and Python, and a passion for building impactful products in a flexible, remote-first environment.

Benefits

Equity in a high-potential, early-stage company

Flexible hours and remote-first culture

Influence over product and technical direction

Qualifications

• 10+ years of experience, with a minimum of 5 years in Flutter, Python, and AWS.
• Experience in building clean, scalable, production-ready applications.
• Curiosity and mission-driven mindset.

Responsibilities

• Lead frontend and backend development of the Nanu platform.
• Build scalable features using Flutter and FastAPI.
• Collaborate with founder and lead developers.

Skills

Flutter

Python

AWS

AI

Tools

PostgreSQL

FastAPI

Redis

SQLAlchemy

Job description

Job Title: Senior Full Stack Developer (Equity Only | Remote | Flutter + FastAPI)

Company: Unknown Systems

Location: Remote (London-based preferred)

Job Type: Equity-Only | Part-Time or Flexible Hours

About the Role

Unknown Systems is building Nanu, a groundbreaking platform that investigates unexplained phenomena through community-submitted experiences and AI-powered tools.

We're looking for a Senior Full Stack Developer to join us at a pivotal moment. This is an equity-only role perfect for someone excited by early-stage building, who wants to help launch something truly unique.

You’ll Be Responsible For:

• Leading frontend and backend development of the Nanu platform
• Building scalable features using Flutter and FastAPI
• Collaborating closely with our founder and lead developers
• Contributing to architecture, infrastructure, and product evolution
• Helping shape the future of a global community-driven product

Our Tech Stack:

• Frontend: Flutter (iOS, Android, Web)
• Backend: FastAPI, Python
• Database: PostgreSQL
• Auth: AWS Cognito
• Infra: Redis, Alembic, SQLAlchemy, Pydantic, Pytest
• AI: OpenAI API integrations
• Feed: Multi-factor ranking system for personalised content

You’re a Great Fit If You:

• Have 10+ years of experience (min 5+ with Flutter, Python, AWS)
• Love building clean, scalable, production-ready apps
• Thrive in startup environments and take ownership
• Are curious, open-minded, and mission-driven
• Bonus: experience with AI, community platforms, or content moderation

What We Offer:

• Equity in a high-potential, early-stage company
• Flexible hours and remote-first culture
• Influence over product and technical direction
• A chance to build something that truly matters