Senior Software Engineer (Java / Kotlin) - Product Page

Allegro operates at a massive scale maintaining critical backend infrastructure for the checkout and purchase path. The Razor team handles backend services operating on nearly 500 instances with traffic up to 50,000 requests per second. The company maintains over 1000 microservices, an open-source data bus (Hermes) with 300K+ rps, a Service Mesh with 1M+ rps, and production-used machine learning., The team works with technologies including Java, Kotlin, Spring, MongoDB, microservices, and Airflow in a cloud-native environment (GCP).

• Minimum 5 years of commercial experience building and maintaining complex, high-scalability systems.
• Proficiency in Java (primary) and Kotlin, focusing on reactive programming.
• Business-oriented mindset with experience collaborating with Product Managers.
• Strong team collaboration skills.
• Readiness to participate in on-call duties.

Nice to have:

• Hands-on experience and advanced knowledge of MongoDB.

• Design, build, and optimize systems handling thousands of requests per second with high availability and performance.
• Participate in structured on-call rotations to ensure system stability.
• Collaborate frequently with other technical teams to deliver shared goals.
• Partner with Product Managers to analyze and drive business initiatives.
• Develop and maintain microservices from design to deployment following the "you build it, you run it" philosophy.
• Participate in developing new tools based on Large Language Models.
• Mentor colleagues with less experience and share knowledge within the team.