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Wallester Software Engineer - Backend in Tallinn, Estonia

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 clients to launch card programs quickly and efficiently.

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 Backend Software Engineer at Wallester, you will be a system owner responsible for designing, building, and operating the core services that power our fintech platform.

This is not a narrow implementation role. You will shape technical solutions, make architectural decisions within your domain, and take responsibility for delivering reliable, scalable services in production.

We operate in a high-availability, regulated fintech environment - engineering quality, security, and reliability are not optional. You will work across the full lifecycle: from problem definition and design to deployment, monitoring, and continuous improvement.

Depending on your experience and impact, you will contribute to or lead architectural initiatives and help drive engineering standards across the organization.

Technology stack

  • Golang

  • gRPC

  • Protocol Buffers

  • PostgreSQL

  • Redis

  • JSON REST API

  • Docker

  • Kubernetes

  • Linkerd

  • AWS infrastructure

  • Microservice Architecture

    Responsibilities

At Wallester, backend engineers are system owners. They design, build, and operate the services that power our fintech platform.

You will take full ownership of the services and features you work on — from idea to production. This includes understanding the business problem, shaping the technical solution, implementing it, and ensuring it runs reliably at scale.

Engineers are expected to take responsibility for production systems, proactively improve reliability, and contribute to operational excellence.

Specifically, you will:

  • Own features end-to-end - from technical design and implementation to deployment, monitoring, and continuous improvement

  • Design and evolve backend services and system architecture in a high-scale, high-availability fintech environment

  • Make thoughtful architectural decisions that balance scalability, reliability, performance, and simplicity

  • Drive engineering standards, code quality, and best practices across the team

  • Actively contribute to improving development processes, CI/CD pipelines, observability, and reliability practices

  • Collaborate closely with Product, QA, and other engineering teams to deliver robust solutions

  • Take responsibility for production stability, debugging complex issues, and improving system resilience

  • Mentor peers through code reviews, knowledge sharing, and technical discussions

We expect all engineers - mid and senior - to demonstrate ownership, initiative, and technical leadership within their scope.

Senior-level engineers additionally:

  • Lead architectural initiatives and cross-team technical efforts

  • Define long-term technical direction in key domains

  • Drive consistency and quality across services and teams

  • Act as technical mentors and multipliers within the engineering organization

    Requirements

We're looking for engineers who think in systems, take ownership, and care deeply about building reliable software.

You likely have:

  • 3+ years of professional backend development experience (5+ years typically for senior level)

  • Strong experience building and operating microservice-based systems

  • Solid understanding of API design (REST / RPC), distributed systems, and service communication patterns

  • Experience working with relational databases such as PostgreSQL and designing efficient data models

  • Hands-on experience with Docker and containerized environments

  • Experience working in cloud environments (AWS / GCP / Azure)

  • Practical experience with CI/CD pipelines and modern software delivery practices

  • Good understanding of testing strategies (unit, integration, and system-level testing)

  • Strong problem-solving skills and ability to debug complex production issues

  • Good English communication skills and ability to collaborate effectively in cross-functional teams

Beyond technical skills, we expect you to:

  • Take ownership of features and services end-to-end

  • Be comfortable making architectural decisions within your domain

  • Drive improvements in engineering standards and processes

  • Work independently and proactively in a fast-paced environment

  • Take responsibility for the quality and reliability of your code in production

    For Senior-Level Candidates

In addition, senior engineers typically demonstrate:

  • Proven experience designing scalable, high-availability backend architectures

  • Strong understanding of distributed systems trade-offs

  • Ability to lead complex technical initiatives across teams

  • Experience mentoring engineers and raising the overall technical bar

  • Consistent ability to make sound technical decisions under ambiguity

    Nice to have

While not required, the following experience will help you ramp up faster and have greater impact:

  • Experience working with Golang in production environments

  • Experience building high-load, high-availability distributed systems

  • Background in fintech, payments, banking, or other regulated industries

  • Familiarity with security best practices and standards (OWASP, PCI DSS)

  • Experience improving system observability (metrics, logging, tracing)

  • Experience designing fault-tolerant systems and handling failure scenarios gracefully

  • Knowledge of service mesh technologies (e.g., Linkerd)

  • Experience working with Kubernetes in production environments

  • Experience participating in system design reviews or architecture discussions

  • Experience driving refactoring initiatives or improving legacy systems

  • Experience contributing to internal engineering standards or platform improvements

A genuine curiosity for technology and a strong engineering mindset always stand 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

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