At Doctolib we build products that need to scale to millions of people throughout Europe and to remain yet easily maintainable by hundreds of developers. We do several daily deployments and run 25K+ automated tests through our CI pipeline. The backend runs on Ruby on Rails, backed by PostgreSQL and MongoDB. Our PostgreSQL databases represent a total of 30TB and receive 30M queries by minute under high traffic.

The team that you will join is responsible for:

• Improving and protecting the health of our data stores,
• Empowering the whole tech team to use our data stores most efficiently,
• Collaborating every day with our Database Administrators, Principal Engineers, and Site Reliability Engineers.

We are seeking a Senior Engineer to join our team to play a critical role in our mission.

As a Senior Engineer on our Doctolib Database Optimization team, you will be at the forefront of maintaining the health of our databases. You will:

• Develop and improve core components to make database workloads more efficient.
• Educate and empower feature teams on database best practices.
• Help break down our main PostgreSQL database into smaller, more scalable databases.
• Mentor junior engineers.
• Keep an eye on query performance and offer suggestions to feature teams on how to optimize it.
• Set up monitoring and alerting to catch performance issues.

Before you read on, if you don't have the exact profile described below, but you feel this job description matches your skill set, we still encourage you to apply!

• You are proficient in Java, or Ruby on Rails, or similar language, and champion coding best practices while upholding security and code quality standards.
• You have proficiency with Java or Ruby on Rails or a similar programming language.
• You have hands-on experience identifying and rectifying database performance bottlenecks with at least one SQL relational database such as PostgreSQL.
• You possess excellent communication skills to efficiently transmit knowledge and foster an environment of intellectual exchange and continuous improvement with both junior and senior team members.

Now, it would be fantastic if you also:

• Have faced challenges of high-traffic web applications, particularly scalability challenges on large databases.
• Have experience with non-relational databases such as MongoDB or with Change Data Capture ecosystems & technologies such as Kafka and Debezium.

• 45min phone screen with a Tech Recruiter
• 1h Live coding interview
• 1h15 System design interview
• 1h15 Behavioral interview
• Half-day immersion