C2 Software Frontend Engineer

Harmattan AI; Paris; On-site; EUR 70,000 - 120,000; Full time

Job summary

Harmattan AI in Paris is seeking a Front-End Engineer to build the operator's viewport into the battlefield. You will craft the Human-Machine Interface for our C2 system, delivering real-time COP updates and multi-stream video handling on tactical PCs.

Collaborate with UX/UI, backend, and mission planning teams to optimize performance, reduce cognitive load, and ensure 60fps rendering. Familiarity with Mapbox/Cesium is a plus.

Qualifications

• Educational background in Computer Science, Software Engineering, or a related field.
• Experience shipping production-grade web apps with complex data visualisation.
• Strong focus on performance and state management.

Responsibilities

• COP Visualization: interactive maps and 2D/3D overlays with real-time telemetry.
• Real-Time Video Grid: multi-stream video UI with low latency.
• Mission Planning & Command: tools for drawing waypoints and issuing commands.
• Performance Architecture: state management for high-frequency data without UI jitter.
• Collaborative Development: partner with UX/UI, backend, and algorithms.
• Optimization: maintain 60fps rendering during updates.

Skills

State management

Real-time data flow

Geospatial mapping

React

Vue

WebGL/Canvas

UX & cognitive load

Ownership & leadership

Adaptability

Education

B.S./M.Sc. in CS/Software Eng

Tools

Mapbox

Leaflet

Cesium

Job description

About Us

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.

About The Role

We are seeking a highly skilled Front-End Engineer to join our C2 Core team in Paris. In this role, you will be responsible for the operator's viewport into the battlefield, building the Human-Machine Interface (HMI) for our tactical Command and Control (C2) system.

You will enter a context where cognitive load management is just as critical as software performance. The UI you build will run on tactical PCs in the field, requiring seamless real-time updates for the Common Operational Picture (COP), rendering multiple live video streams, and providing an intuitive interface for planning missions and commanding a fleet of robots.

Responsibilities

• COP Visualization: Build interactive maps and 2D/3D geospatial overlays displaying real-time robot telemetry, sensor data, and mission routes.


• Real-Time Video Grid: Develop a low-latency, resilient video player interface capable of handling multiple simultaneous streams without freezing the main UI thread.


• Mission Planning & Command: Create interactive tools for operators to draw waypoints, set mission parameters, and issue instant commands to the fleet.


• Performance Architecture: Design a state management system capable of processing high-frequency data from the backend bus without causing UI jitter or memory leaks.


• Collaborative Development: Work closely with UX/UI designers, backend engineers, and mission planning algorithm designers to refine workflows and ensure absolute minimum clicks for the operator.


• Optimisation: Ensure the UI maintains strict performance benchmarks, such as consistent 60fps rendering, even during high-frequency map updates.

Candidate Requirements

• Educational Background: B.S. or M.Sc. in Computer Science, Software Engineering, or a related field.


• Professional Experience: At least 5-6 years of experience shipping production-grade web applications with complex data visualisation.

Technical Expertise

• Deep understanding of complex state management and real-time data flow.


• Experience with geospatial mapping libraries (e.g., Mapbox, Leaflet, Cesium) or rendering APIs (WebGL, Canvas).


• Familiarity with modern frameworks like React or Vue.


• Domain Knowledge: Previous experience in defense, aerospace, fintech, or high-reliability domains where real-time data rendering is critical.


• UX & Cognitive Load Awareness: High degree of user empathy; ability to design interfaces for high-stress environments where operators cannot afford distractions or confusing error states.


• Proven Leadership & Ownership: A "mission-driven" and "product-oriented" mindset with a willingness to take full ownership of the frontend architecture.


• Adaptability: Ability to thrive in a fast-paced, multi-disciplinary startup environment.

We look forward to hearing how you can help shape the future of autonomous defense systems at Harmattan AI.