Senior Technical Support Engineer

Are you looking for an exciting opportunity to join a fast-growing fintech company that is revolutionizing the payment industry? Do you want to work with cutting-edge technologies and a talented team of professionals? If yes, then Wallester AS might be the perfect place for you Wallester AS is an Estonian licensed payment service provider that develops financial digital technology and issues VISA cards. Since 2018, we have been an official Visa partner and Visa FinTech Fast Track Member issuing physical and virtual cards of any type: debit cards, credit cards, prepaid cards, and cards for business. Our distinctive advantage is a unique REST API created by our in-house development team. Easily integrated with any platform, it allows you to launch your card program in no time We are looking for passionate and driven individuals who share our vision of creating truly high-quality and profitable products for our clients.

As a Senior Technical Support Engineer at Wallester, you will play a critical role in resolving complex technical issues reported by our clients and internal teams. You'll take full ownership of high-impact incidents, working across backend services, APIs, infrastructure, and databases to ensure fast and accurate solutions that directly improve the customer experience and system resilience.

This senior role demands strong technical acumen, autonomy, and a customer-first mindset. You will lead escalations, contribute to incident strategy, mentor other support engineers, and work closely with Support, Operations, Engineering, and DevOps teams to continuously strengthen our troubleshooting practices and platform reliability. If you thrive in complex technical environments and want to drive meaningful impact in a fast-paced fintech setting, we'd love to meet you.

• Golang
• PostgreSQL
• Redis
• JSON REST API
• Kubernetes
• AWS infrastructure
• Microservices Architecture
• ElasticSearch
• Kibana
• Prometheus
• Grafana
• OpsGenie

• Serve as the final escalation point for incidents from the Operations (L2) team, taking full ownership through resolution.
• Diagnose and troubleshoot backend, API, and infrastructure-related issues, leading resolution for priority incidents.
• Resolve minor issues independently and escalate when necessary, based on scope or urgency.
• Own root cause analysis (RCA) for complex issues and coordinate with Engineering and DevOps to deliver lasting solutions.
• Maintain and improve internal documentation, knowledge base articles, and runbooks.
• Automate repetitive investigation or diagnostic tasks using scripts or internal tools.
• Monitor system alerts and logs proactively to detect and prevent issues.
• Track internal SLAs for incident response and resolution, and recommend optimizations to reduce impact.
• Participate in post-incident reviews and facilitate RCA meetings where required.
• Collaborate with DevOps and Engineering to improve observability, logging, and alerting.
• Support audit readiness by documenting recurring issues, resolution steps, and operational procedures.
• Mentor support engineers and contribute to onboarding and continuous learning efforts.
• Take part in on-call rotations and act as the escalation lead during major incidents.

• 5+ years of experience in technical support, software engineering, or SRE roles.
• Experience troubleshooting backend and microservice-based systems using logs, API traffic, request tracing, and service interactions.
• Skilled in identifying and resolving database issues, including performance tuning, slow queries, and data inconsistencies.
• Proven ability to lead troubleshooting efforts across services, infrastructure, and third-party integrations.
• Experience mentoring engineers or support staff and driving support process improvements.
• Strong sense of ownership, initiative, and ability to work independently.
• Familiarity with observability tools like Prometheus, Grafana, ELK stack, CloudWatch, Rollbar, or Honeycomb.
• Excellent communication skills, with the ability to explain complex issues clearly to both technical and non-technical audiences.
• Solid analytical thinking, documentation habits, and incident management capabilities.
• Ability to work effectively across functions in high-pressure or time-sensitive situations.

• Prior experience supporting payment systems or fintech platforms.
• Understanding of card issuing platforms and APIs (e.g., Visa, Mastercard ecosystems).
• Experience writing diagnostic scripts in Python, Go, or Bash.
• Knowledge of security and compliance frameworks such as PCI-DSS, OWASP or ISO27001.
• Familiarity with CI/CD workflows and deployment pipelines to track releases, investigate deployment-related issues, and support troubleshooting.

Also, a spark in the eyes is always a plus

• Competitive salary
• Development and career opportunities
• Medical Insurance upon the completion of the probationary period
• Supportive and caring Leadership
• A modern office in the center of Tallinn
• A chance to work as part of a highly motivated and talented team
• Referral program
• Stebby
• Team building and Company Events
• Free parking