Senior Software Engineer
Fullstack Software Engineer (Python / TypeScript / React)
📍 Paris (Morning Laffitte) | Full-time | 2 remote days per week
🌍 Tech Team | Role split 70% backend / 30% frontend
About Symbiotic Security
Symbiotic Security is a cybersecurity startup helping developers write secure code through an AI-powered assistant integrated into their IDE and CI/CD pipelines. Our solution has two unique strengths: it provides developers with interactive training to understand vulnerabilities as they code, and it automatically detects and remediates security flaws introduced by generative AI tools such as GitHub Copilot.
➡️ Founded in April 2024
➡️ 16 team members split between Paris (Tech team) and New York (Sales team)
➡️ Goal: 15 new hires by the end of 2026
Our offices are located at Morning Laffitte (Paris 9ᵗʰ) — bright open spaces with collaborative areas, a friendly atmosphere, and a focus on productivity.
Tech Stack & Environment
- Backend: Python 3.12+ / Django (monolith, REST API)
- Frontend: TypeScript / React (SPA) for the frontend of the SaaS platform,
- Typescript for the IDE plugin
- Database: PostgreSQL
- Architecture: Monolithic - Hexagonal, DDD being introduced
- Tests: 94% backend coverage, 100% business logic covered
- Tools: Sentry, logs, traces, internal analytics
- Satellite services: CLI tools & AI agents written in Python
Your Mission
- Contribute to both the backend (70%) and frontend (30%) of our SaaS product.
- Participate in the design and evolution of our hexagonal architecture and DDD approach.
- Collaborate closely with Abir (Engineering Manager), Minh Thang (Tech lead) and Édouard (CTO) on technical and product decisions.
- Work on diverse projects: REST APIs, CLI tools, AI agents, performance optimization.
- Lead continuous improvement initiatives, such as code reviews, automated testing, and release management.
- Offer technical guidance to team members, fostering a culture of learning and professional development.
What We’re Looking For
Core Skills
- Master's degree in Computer Science or related field.
- Proven experience (min 5 years) as a software engineer, with a strong track record of designing and delivering complex software systems, Python and TypeScript required ✅
- Demonstrated expertise in backend development using Python. An experience of Django would be a strong plus.
- Demonstrated expertise in frontend development using Typescript / React.
- Solid SQL knowledge (PostgreSQL preferred)
Appreciated
- Experience working with Product Manager, Product Designer, or UI/UX person.
- Strong grasp of clean code principles (SOLID, DRY, YAGNI)
- Understanding or curiosity for DDD
- Monitoring / logging / API optimization = big plus
- Comfortable using LLMs (ChatGPT, Copilot, Claude)
Soft Skills & Mindset
- Early-stage startup mindset: autonomous, fast, impact-driven
- Curious, rigorous, and eager to understand before acting
- Strong communicator, collaborative, no ego
- Capable of challenging ideas and defending opinions constructively
- Product-oriented with a desire to build meaningful software
- Work-life balance valued
What You’ll Have Achieved
Timeframe Key Milestones
3 months First features shipped, ramp-up on the stack, contribution to testing pipeline
6 months Leading a technical scope, improving architecture, driving performance or monitoring initiatives
12 months Recognized internal expert / coach within the team
Methodology & Culture
- Agile-ish organization (2-week sprints, continuous releases)
- Systematic code reviews
- Occasional pair programming
- Mix of maintenance, new features, and R&D work
- Monthly “Bug Day” (stress testing the product)
- “Cool down period” planned for internal tech projects
💡 AI culture: every developer is encouraged to use ChatGPT, Copilot, or Claude as part of their workflow.
Team
Our product team brings together diverse profiles working collaboratively: fullstack engineers, AI engineers, cybersecurity experts, product managers, and product designers: all coming from different backgrounds.
- 👩💻 MT – Lead Engineer
- 👩💻 Abir – Engineering Manager
- 👨💻 Édouard – CTO
Team culture:
- Collaboration > hierarchy
- Technically demanding but kind environment
- No-ego culture
- Strong product–tech alignment
Compensation & Benefits
💰 BSPCE (equity) available
🏥 100% health insurance coverage
🍽️ Swile meal card
💻 €500 equipment budget
🚲 Allowance for Sustainable Commuting (e.g., cycling, carpooling, public transport)
🏖️ RTT + paid vacation
🏡 2 remote days per week
🪴 Important opportunities for career advancement and professional development by being a pioneer within a new company.
🧑🔬 Strong product & engineering culture in the company.
🥂 Vibrant and inclusive company culture with regular team outings and events.
☝🏽 Chance to make a meaningful impact and shape the future of Symbiotic.
👭 Referral bonus: €2,000
Hiring Process
We respect your time and will make it quick and efficient. All of that will be completed within two weeks.
- Call with our Talent Acquisition - Blanche - 30 minutes
- Meeting with our Engineering Manager - Abir - 45 minutes to 1 hour.
- On-site technical test with our tech lead - Minh Thang - 1,5 hour.
- Culture fit - Meeting with the CTO and lunch with the team - 2 hours
- Formal hiring proposal.