Senior Software Engineer - Freelance

English is mandatory

Mission Context

As part of the reinforcement of an Engineering team dedicated to booking journeys, we are looking for a Senior Software Engineer able to work on critical backend and API topics within a high-traffic environment, strongly focused on performance, reliability, scalability, and delivery excellence.

The Booking team is at the core of the platform. It works on topics directly related to the booking funnel, availability, transaction security, API robustness, and the overall quality of the user experience.

A key part of the mission will be to contribute to the design and development of a new API layer aimed at decoupling the frontend from the existing backend systems. This API will become a central component of the Booking architecture, requiring a strong API-first mindset, solid system design capabilities, and a high level of engineering maturity.

The stack includes PHP, but the goal is not to hire a pure PHP expert. We are primarily looking for a senior Software Engineer who can quickly understand a complex environment, deliver efficiently, and bring a strong 360° engineering mindset across architecture, API design, testing, CI/CD, scalability, performance, security, and observability.

Role and Responsibilities

The main responsibilities will include:

• Designing, developing, maintaining, and evolving backend services, mainly in a PHP environment

• Contributing to the construction of an API layer designed to decouple the frontend from backend systems

• Working with an API-first approach, including OpenAPI specifications, API contracts, and robust API design

• Implementing and improving automated API testing to secure API quality, reliability, and non-regression

• Quickly understanding the existing architecture and integrating efficiently into a high-traffic information system

• Participating in technical design decisions, beyond simply executing tickets

• Improving the reliability, performance, scalability, and maintainability of services

• Working on API-related topics: security, robustness, contracts, performance, monitoring, and error handling

• Contributing to CI/CD practices and ensuring high-quality delivery pipelines

• Identifying technical risks and proposing pragmatic solutions

• Being proactive on architecture, code quality, observability, testing strategy, and industrialization topics

• Collaborating with Engineering Managers, Product Managers, frontend engineers, backend engineers, and other technical teams

• Using AI tools intelligently to accelerate development, improve quality, and increase productivity, while maintaining critical thinking and technical ownership

Recruitment Process

The process includes three steps:

1. Live coding with the Engineering Manager

2. System Design interview with the Engineering Manager

3. Technical discussion with the VP Engineering