OneMain Financial Jobs

About us

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.

About the role

As a Technical Support Engineer at Wallester, you will be the technical escalation point for complex issues affecting our fintech platform.

This is not a first-line support role. You will take ownership of high-impact incidents across backend services, APIs, infrastructure, and databases, ensuring fast resolution and long-term reliability improvements.

You will work closely with Operations (L2), Engineering, and DevOps teams to diagnose problems, identify root causes, and implement durable fixes. In a regulated, high-availability fintech environment, precision, accountability, and clear communication are critical.

This role requires strong technical depth, structured thinking, and a proactive mindset focused on system reliability and operational excellence.

Technology stack

• Golang

• PostgreSQL

• Redis

• JSON REST API

• Kubernetes

• AWS infrastructure

• Microservices Architecture

• ElasticSearch

• Kibana

• Prometheus

• Grafana

• OpsGenie

  What will you do?

At Wallester, Technical Support Engineers are system problem-solvers and reliability drivers.

You will take full ownership of complex technical incidents — from investigation to resolution and root cause analysis — ensuring issues are not only fixed, but permanently addressed.

Specifically, you will:

• Serve as the final escalation point for incidents from L2 Operations

• Diagnose backend, API, database, and infrastructure-related issues using logs, traces, metrics, and request flows

• Lead root cause analysis (RCA) for complex incidents and coordinate cross-team resolution

• Collaborate with Engineering and DevOps to implement long-term fixes and reduce recurrence

• Monitor alerts and system health proactively to detect and prevent incidents

• Improve observability, logging, and alerting practices in partnership with engineering teams

• Maintain and evolve runbooks, internal documentation, and troubleshooting guides

• Automate repetitive investigation steps using scripts or internal tooling

• Track internal SLAs and drive improvements in incident response and resolution time

• Participate in post-incident reviews and contribute to operational improvements

• Support audit readiness through clear documentation of processes and recurring issues

• Participate in on-call rotations

We expect L3 engineers to demonstrate ownership, analytical rigor, and cross-functional leadership during high-pressure situations.

What you'll need

We're looking for engineers who are comfortable navigating distributed systems and diagnosing complex production issues.

You likely have:

• 3+ years of experience in technical support, SRE, backend engineering, or similar roles (5+ years typical for senior-level scope)

• Strong experience troubleshooting backend and microservice-based systems

• Practical experience analyzing logs, API traffic, request tracing, and service interactions

• Experience identifying and resolving database-related issues (performance, slow queries, data inconsistencies)

• Familiarity with observability tools such as Prometheus, Grafana, ELK stack, CloudWatch, Rollbar, or similar

• Strong analytical thinking and structured incident management approach

• Ability to work cross-functionally in time-sensitive or high-pressure situations

• Clear communication skills — able to explain complex technical issues to both technical and non-technical stakeholders

• Strong sense of ownership and ability to drive issues to resolution independently

For engineers operating at senior scope, we additionally expect:

• Experience leading high-severity incident response

• Proven ability to drive cross-team troubleshooting efforts

• Experience mentoring other support engineers

• Experience improving monitoring, alerting, and support processes

  Nice to have

• Prior experience supporting payment systems or fintech platforms

• Understanding of card issuing platforms and APIs (Visa, Mastercard ecosystems)

• Experience writing diagnostic scripts in Python, Go, or Bash

• Knowledge of security and compliance standards (PCI-DSS, OWASP, ISO27001)

• Familiarity with CI/CD pipelines and deployment workflows

• Experience working in regulated, high-availability environments

A strong sense of curiosity, precision, and operational discipline always stands out.

​We offer

• 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