Software Engineer - Front

sunday

10d • Hybrid

About The Position

sunday is hiring a Senior Software Engineer to design and deliver high-impact full-stack features, from Kotlin backend development to React frontend experiences, while accelerating software development through AI agents. The role reports to Nicolas and is part of the Tech team. The engineer will own complex technical challenges, make pragmatic trade-offs among speed, simplicity, and robustness, and contribute to production services capable of handling high loads.

The position also focuses on improving engineering practices and team efficiency through agentic AI, designing reliable software and scalable solutions, and sharing technical standards and learnings to help the team grow. The role is based on a hybrid working model, combining office presence in Paris with remote work, and has a 39-hour working week under executive employee status.

Requirements

• Several years of full-stack development experience.
• Strong hands-on expertise in Kotlin on the backend and React.js on the frontend.
• Proven experience deploying and operating high-load services in production.
• Hands-on experience writing code with AI agents or AI-assisted development tools.
• Ability to reason about architecture, reliability, and technical trade-offs.
• Strong business acumen and ability to prioritize based on the impact of decisions.
• Fluency in spoken and written French and English.

Nice To Haves

• Strong ownership and a tendency to tackle problems without waiting for permission.
• Entrepreneurial mindset, adaptability, and willingness to thrive in ambiguous environments.
• Independent thinking and ability to reframe problems and find simple, original, evidence-based solutions.
• Focus on impact, clear trade-offs, and applying the 80/20 principle.
• Positive energy, a collaborative mindset, and desire to help the entire team succeed beyond individual scope.
• Intellectual curiosity, ability to learn quickly, and desire to keep improving.

Responsibilities

• Design and deliver full-stack features, including Kotlin backend services and React.js frontend applications.
• Write code using AI agents and help build an agentic software factory.
• Take ownership of complex software design, architecture, and service reliability topics.
• Design solutions capable of running in production at scale.
• Improve development practices and Engineering team efficiency through agentic AI.
• Make pragmatic technical decisions that account for business impact, simplicity, and execution speed.
• Share standards, learnings, and technical convictions to help the team grow.

Benefits

• Competitive package depending on experience, plus stock options.
• Unlimited paid time off.
• Significant ownership and opportunities for career growth.
• 100% employer-paid health insurance coverage for the employee and their children.
• 50% reimbursement of public transportation pass.
• Beautiful offices in the heart of Paris, in the Sentier district.
• Hybrid working model combining office presence and remote work.
• €50 per month towards remote-working expenses.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed