C2 Software Backend Engineer

We are looking for a dedicated Backend Software Engineer to join our C2 Core team in Paris to build the "nervous system" of our new tactical Command and Control (C2) application. You will enter a highly technical, mission-critical environment where low latency, fault tolerance, and secure data handling are paramount.

You will be responsible for the core architecture that ensures real-time telemetry, heavy video streams, and mission commands flow seamlessly between our robot fleet and internal C2 components, such as the Common Operational Picture (COP) and Mission Planner. This system is designed to run on ruggedized, resource-constrained tactical PCs in the field, often under degraded network conditions., * Robot-to-C2 Communications Gateway: Design and implement ingestion pipelines for high-frequency telemetry and video streams from multiple robots simultaneously.

• Internal Messaging & IPC: Build the inter-process communication (IPC) or local pub/sub systems to route sensor data, user commands, and mission plans between the HMI and the robot fleet.
• Resource Optimisation: Ensure the backend runs efficiently on local tactical PCs, managing CPU and memory footprints to prevent interference with UI or planning algorithms.
• Fault Tolerance: Architect state machines capable of handling the chaos of tactical environments, including frequent network drops and packet loss, without corrupting the Common Operational Picture.
• Cross-Functional Collaboration: Partner with Mission Planning algorithm designers, HMI frontend developers, and UX designers to deliver a cohesive product .

Do you have experience in gRPC?, Do you have a Bachelor's degree?, * Educational Background: B.S. or M.Sc. in Computer Science, Software Engineering, or a related field

• Experience shipping production-grade applications with complex data visualization and real-time UI requirements. Technical Skills:

• Strong command of system-level languages such as C++, Rust, or Go.

• Deep expertise in Real-Time Networking (UDP, TCP, WebRTC, gRPC, DDS, or custom binary protocols).

• Expertise in Systems Architecture & IPC, specifically using bounded ring buffers or zero-copy shared memory for high-concurrency pipelines.

• Proficiency in profiling and capping resource footprints using tools like perf or cgroups.

• Soft Skills: * Ownership & Mission-Driven: A high degree of commitment to Harmattan AI's mission and the ability to thrive in a fast-paced startup environment.

• Communication: Ability to mediate technical trade-offs between hardware, algorithm, and frontend teams.

Harmattan AI is a next-generation defense prime building autonomous and scalable defense systems. Following the close of a $200M Series B, valuing the company at $1.4 billion, we are expanding our teams and capabilities to deliver mission-critical systems to allied forces. Our work is guided by clear values: building technologies with real-world impact, pursuing excellence in everything we do, setting ambitious goals, and taking on the hardest technical challenges. We operate in a demanding environment where rigor, ownership, and execution are expected.