Senior Software Engineer

TechTree; Paris; On-site; EUR 85,000 - 105,000; Full time

Job summary

TechTree is seeking a Senior Software Engineer to build real-time voice and audio systems from zero for European defence customers. Paris or Warsaw, on-site.

You'll work closely with the founders to ship prototypes and iterate with early customers, tackling low-latency audio and streaming challenges. Based in Paris or Warsaw, relocation support available.

We value pragmatic, product-minded engineers who can explain complex systems clearly and thrive in fast-moving environments.

Qualifications

• Experience shipping real-time voice/audio systems.
• Ability to work with early customers and iterate quickly.
• Strong execution in ambiguous, fast-moving environments.

Responsibilities

• Ship and iterate on prototype deployments directly with early customers
• Get hands-on with bespoke audio streaming tech and real-time voice systems
• Build from zero alongside the founding team

Skills

Real-time audio

Low-latency

Prototype deployment

Job description

Senior Software Engineer — Build real-time voice and audio systems from zero for European defence customers. Paris or Warsaw, on-site.

A European defence startup based between Paris and Warsaw is building modern software tailored for hostile environments. Customers include European military and police units. Recognised as one of France’s top 20 seed companies and backed by Europe’s leading defence VC and angels including the founders of Cloudflare, Quantum Systems, and ElevenLabs. Founding team: two early Cloudflare employees and a former GIGN commander. No weapons systems. No hardware.

You’ll work closely with the founders to iterate quickly on deployments of prototypes with early customers.

What You'll Do

• Ship and iterate on prototype deployments directly with early customers
• Get hands-on with bespoke audio streaming tech and real-time voice systems
• Build from zero alongside the founding team

What We're Looking For

• Pragmatic, product-minded software engineering generalist with strong execution skills
• Thrives in ambiguous, fast-moving environments
• Can explain complex technical systems in simple ways
• Speaks French and English

Bonus

• Worked with LLMs, or built pipelines
• Comfortable with audio processing and low-latency systems
• Experience in on-prem environments
• Implemented AI systems in resource-constrained environments
• Experience working with armed forces

Location: Paris or Warsaw, on-site (relocation support available)

Compensation: €85–105K + equity, depending on experience

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