Hybrid L2 Technical Support Engineer - API & SQL Debugging

Arsenal Growth Equity; Kraków; Hybrid; PLN 134,000 - 179,000; Full time

Benefits offered by this job

Hybrid work model

Job summary

OneRail in Kraków is seeking a Technical Support Engineer (L2) to serve as a front-line technical partner for our customers. In this hands-on role, you’ll handle issues end-to-end, perform triage and deep investigation across APIs, databases, and integrations, and work closely with Engineering on escalations.

This position requires 2–4 years in a technical or customer-facing role, strong troubleshooting, ability to read code (JavaScript/TypeScript), and fluent English & Polish (B2+).

Qualifications

• 2–4 years in technical support, product support, or customer-facing technical role.
• Strong troubleshooting skills and independent problem solving.
• Ability to read and understand code (JavaScript/TypeScript preferred).
• Experience debugging REST APIs and using SQL for investigations.
• Fluent English and Polish (B2+), clear written and verbal communication.

Responsibilities

• Serve as primary technical support contact for customer issues.
• Triage issues by severity, impact, and scope.
• Investigate problems using logs, API requests, and SQL queries.
• Reproduce issues and document steps and outcomes clearly.
• Use AI-assisted tools to accelerate code understanding and debugging.
• Escalate to Engineering with high-quality context and next steps.
• Explain technical findings to stakeholders and customers.
• Maintain and improve support documentation and runbooks.
• Identify recurring issues and suggest tooling or process improvements.

Skills

Troubleshooting

REST APIs

SQL

Code reading (JS/TS)

English & Polish

Job description

OneRail in Kraków is seeking a Technical Support Engineer (L2) to serve as a front-line technical partner for our customers. In this hands-on role, you’ll handle issues end-to-end, perform triage and deep investigation across APIs, databases, and integrations, and work closely with Engineering on escalations.

This position requires 2–4 years in a technical or customer-facing role, strong troubleshooting, ability to read code (JavaScript/TypeScript), and fluent English & Polish (B2+).