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Freelance Fullstack Developer (f/m/d) – Security Code Review in Frankfurt am Main
For an innovative technology company in the field of cyber security and SecOps, we are currently looking, on behalf of one of our clients, for an experienced Fullstack Developer (f/m/d) with a strong security background on a freelance basis.
The company develops specialized platform solutions for the detection, analysis, and protection of complex IT infrastructures. As part of the ongoing development of an existing SecOps platform, a comprehensive and structured code review is now required.
The focus is not on feature development, but on a deep technical and security-related assessment of an existing system architecture, particularly in the areas of authentication, authorization, multi-tenant logic, and event-driven processing.
This project offers the opportunity to work in a technically challenging environment using modern technologies, contributing to the quality assurance and security hardening of a critical platform.
Your tasks:
- Conduct a comprehensive code review (backend & frontend)
- Analyze the existing system architecture and design decisions
- Evaluate the security implementation (authentication, RBAC, tenant isolation)
- Identify security risks (e.g. auth bypasses, injection vulnerabilities, logic flaws)
- Review event-driven components (Redis Streams, Consumer Groups)
- Analyze scheduler implementations (e.g. APScheduler)
- Create a structured and well-documented review report
- Derive concrete recommendations for improvement
Your profile:
- Several years of experience as a Fullstack Developer with a strong backend and security focus
- Strong expertise in Python (3.10+) and FastAPI
- Experience with MongoDB (aggregation pipelines, indexing, multi-tenant concepts)
- Very good knowledge of Redis (especially Streams and Consumer Groups)
- Solid experience with Async Python (asyncio, httpx, motor)
- Experience with job scheduling (e.g. APScheduler or similar)
- Strong knowledge of React (18/19), Hooks, Context API, and React Router v6
- Experience with Tailwind CSS (including dark mode)
- Understanding of modern frontend authentication patterns (httpOnly cookies, CSRF)
- Proven experience in security topics:
- JWT-based authentication
- RBAC models
- Multi-tenant SaaS architectures
- Ability to identify and assess security vulnerabilities in code
- Basic infrastructure knowledge:
- Linux / systemd
- Nginx (reverse proxy, TLS)
- Docker (Compose, network isolation)
- Independent, structured, and analytical working style
- Excellent English-skills
Nice to have:
Experience with WebSockets and real-time architectures
Experience with security-focused code reviews (beyond code style, focusing on logic and architecture)
Experience in SecOps or cyber security environments
Important note:
This project explicitly targets developers with strong hands-on expertise and deep technical understanding.
We are not looking for someone who relies on AI tools to analyze code, but for a professional who:
- reads and understands code independently
- critically evaluates complex systems
- provides well-founded technical and security assessments
General conditions:
Start: Asap
Duration: approx. 3 months
Location: full remote
Project language: English
Workload: preferably 100% (part-time possible, resulting in longer duration)
This project is specifically aimed at freelancers and offers an excellent opportunity for experts to contribute their skills in a technically demanding and security-critical environment.
We value long-term partnerships with freelancers.
Our goal is to build a trusted collaboration on equal terms, potentially extending beyond this project.
For this project, we offer a rate starting from EUR 90.00 per hour, depending on your qualifications and experience.
We are, of course, open to market-aligned overpayment depending on your expertise and the project requirements.
Sounds interesting?
Then apply now! We look forward to hearing from you!
Your contact person
Mr Matthäus Radulescu
Contact us
Evo.People GmbH
Marxergasse 1B / Top 6
1030 Wien
matthaeus.radulescu@evopeople.at
