Junior Software Engineer (Integrations)

We're looking for you if:

• You have solid coding fundamentals: Strong basics in at least one modern language (preferably Java) — we care about how you think and solve problems rather than syntax memorization.
• Investigative & Problem-Solving Mindset: You enjoy digging into logs, chasing down edge-case bugs, and figuring out why a data feed isn't behaving as expected.
• Comfortable with Support First: You view production maintenance and live bug-fixing not as a chore, but as the fastest way to learn a real-world system.
• Curious About Data Flows: Eager to learn APIs, ETLs, batch processing, file protocols, and how data moves across distributed networks.
• Clear & Transparent Communicator: You raise flags early when stuck, ask structured questions, and keep team members updated during incident resolution.

Bonus points

• Basic familiarity with SQL, log monitoring tools, Kafka, or cloud platforms (AWS/GCP).
• Prior experience in IT support, application maintenance, or customer-facing technical support.
• Side projects or academic work involving data parsing, APIs, or data pipelines.

Junior Integrations Engineer

Live Platform Maintenance · Deep System Learning · Pragmatic Development

At CO3, we are standing up a new engineering team to take technical ownership of an active, production-grade logistics platform. We are looking for a Junior Integrations Engineer whose primary focus will be keeping our live integration pipelines healthy and operational—troubleshooting issues, maintaining data feeds, and supporting production—while progressively taking on new development tasks as domain knowledge grows.

Why this role?

• Learn by Maintaining Real Systems: There is no better teacher than production code. By handling maintenance, monitoring, and bug fixes first, you'll gain a deep, practical understanding of how complex, distributed systems actually behave.
• Support as a Launchpad: Operational support is your primary responsibility day-to-day, serving as the foundation for your transition into designing and writing new integration features over time.
• Direct Mentorship: You won't be thrown into the deep end alone. Senior Engineers and a Tech Lead will back you up on difficult operational issues and guide your technical growth.

Your mission

• Primary Focus — Support & Maintenance: Monitor live integration feeds, investigate data flow failures, debug broken connections, and resolve production support tickets to keep platform data reliable.
• Secondary Focus — Development & Refactoring: As you master system behaviour, write bug fixes, refactor legacy integrations, and build new endpoints or automation scripts.
• Troubleshoot Diverse Integration Styles: Dig into REST APIs, Webhooks, ETL pipelines, batch/file transfers (CSV, XML, JSON), and event streams (Kafka) to identify where data gets stuck.
• Improve Runbooks & Tooling: Document failure modes, write diagnostic scripts, and help refine internal developer tools to make future support easier.
• Work AI-Native: Utilize AI tools (Cursor, Claude, MCPs) to rapidly navigate legacy code, parse log outputs, and trace complex domain logic during troubleshooting.

What's in it for you

• • Clear Growth Path: Transition progressively from operational support and maintenance to active integration feature engineering.
  • Real Mentorship: A supportive and experienced team that equips you with the tools, context, and guidance needed to solve live production problems.
  • True Product Environment: One evolving, real-world logistics platform—no body-leasing, no software house routine, and a candid, "No-BS" engineering culture.
  • Flexibility: Remote-first across Poland with an optional Wrocław office setup (Powstańców Śląskich).

,[] Requirements: Testing, AI, Java, Integration, Ownership, REST API, Spring, API, Logistics, C#, Python, Kafka, Cloud, Node.js, TypeScript, ETL Tools: Confluence, GitHub, GIT, Agile, Kanban.