At Doctolib we build products that need to scale to millions of people throughout Europe and to yet remain easily maintainable by hundreds of developers.

The backend runs on Ruby on Rails, backed by PostgreSQL and Redis. On the front side, we bet on React, even for our mobile apps. We do several daily deployments and run 25K+ automated tests through our CI pipeline. Our PostgreSQL databases represent a total of 30TB and receive 30M queries by minute under high traffic.

We are seeking a Senior Engineer to join our team to play a critical role in preserving the performance of our databases.

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:

• Implement code and documentation to evangelize database best practices and empower feature teams to make informed decisions regarding the databases.
• Contribute to the modularization of our main PostgreSQL database into a distributed and scalable ecosystem of smaller databases.
• Monitor query performance and offer insights and recommendations to feature teams for optimization.
• Review code and answer questions about data modeling and access patterns and offer guidance in selecting appropriate data stores.
• Develop core components to optimize database workloads.
• Implement robust monitoring and alerting systems to proactively identify performance bottlenecks, latency issues, and potential system failures at the database level.
• Collaborate everyday with our Database Administrators, Principal Engineers and Site Reliability Engineers to coordinate the whole Tech team’s efforts on the performance and scalability of our databases.
• Mentor junior engineers, and engage in constructive technical discussions with both junior and senior team members, fostering an environment of intellectual exchange and continuous improvement.
• Champion coding best practices, and uphold our security and code quality standards within the team.

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 have proficiency with Java or a similar programming language, and are eager to be hands on with Ruby on Rails (we’ll of course help you ramp up if needed).
• You have hands-on experience with at least one SQL relational database such as PostgreSQL and in identifying and rectifying database performance bottlenecks.
• You are proactive, curious and collaborative.
• You have excellent communication skills, enabling efficient transmission of knowledge, and are eager to leverage your experience and skills to make your team grow.
• You have experience in mentoring junior engineers.
• You have 5+ years of experience as a Software Engineer.
• Speak English.

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 NoSQL databases such as MongoDB.
• Have experience with Change Data Capture ecosystems & technologies such as Kafka and Debezium.

• 30min phone screen with a Tech Recruiter
• 1h Live coding interview
• 1h15 System design interview
• 1h15 Methodology interview
• Half day immersion

• Permanent Position 
• Full time 
• Location: Nantes - onsite/hybrid
• Start Date: as soon as possible
• This job is eligible to hybrid mode. 

At Doctolib, we believe in improving access to healthcare for everyone - regardless of where you come from, what you look like. This translates into our recruitment process: Doctolib is an equal opportunity employer. We don't just accept diversity at Doctolib, we respect and celebrate it!

The more diverse ideas are heard, the more our product will truly improve healthcare for all. You are welcome to apply to Doctolib, regardless of your gender, religion, age, sexual orientation, ethnicity, disability, or place of origin. If you have a disability, let us know if there's any way we can make the interview process smoother for you! 

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