Mid Backend Engineer

Department: Engineering

Location: Bulgaria

Employment Type: FullTime

Our mission is to enable everyone to build wealth

We reinvent how trading and investing work by creating exceptional products people love.

Fostering a culture of excellence and high velocity is the key to our success. Today, we serve over 6 million clients, with more than €40 billion in assets under management — a testament to the scale and trust we've built in just a few years. At that scale, performance, reliability and data integrity are part of the product.

Our platform is powered by a modern, high-performance engineering stack designed for scale and reliability: Java 21 (Spring), Go, Node.js (TypeScript), PostgreSQL, MariaDB, Redis, Kafka, ClickHouse, Elasticsearch, Docker, Grafana, AWS, Kubernetes and OpenSearch.

About the role

Mid Backend Engineers work across our backend organisation. Your team match will reflect your strengths, interests and where you can contribute most.

Across every team, the model is the same: small, autonomous teams, short release cycles and ownership from problem definition through production. You'll be trusted to own well-scoped services and features end to end, with senior engineers on hand for the trickier architectural calls.

What you'll do

• Own features and services end to end — take a business problem, help shape the requirements, design the solution, build it, test it, deploy it and monitor it in production.

• Design for performance, scale and resilience — build code and services that hold up under load, minimise downtime and latency, and degrade gracefully when things go wrong.

• Take real ownership of your code — keep it maintainable as requirements evolve, and know when and how to refactor.

• Diagnose and fix production issues — get to the underlying cause, not just the symptom, and put guardrails in place to stop it recurring.

• Work closely with product and engineering colleagues — turn moderately complex requirements into simple, durable solutions, escalating and collaborating with seniors on the parts that need broader system context.

• Contribute to the team's engineering standard — review others' work constructively, share what you know, and take feedback in stride.

What you need to have

• Solid, hands-on experience delivering backend services in production — you've shipped and operated real systems, ideally within a microservices architecture.

• Proven backend engineering experience in Java, which is the core language of our platform. Candidates with strong production experience in Go or Node.js are also encouraged to apply.

• Proven ownership of backend services built and operated within a microservices architecture.

• Production fluency in at least one modern backend framework (e.g. Spring Boot for Java, or an equivalent in Go or Node.js).

• A strong grasp of communication protocols such as HTTP, WebSockets and AMQP, including when to apply each.

• Deep knowledge of relational databases, including indexing, transactions, isolation levels, locking mechanisms and high-performance design.

• A track record of designing systems for high availability, scalability and resilience.

• Clear, structured problem-solving and the ability to explain technical decisions and trade-offs.

• Strong engineering fundamentals, sound judgement and confidence learning unfamiliar technologies.

Depth in one backend ecosystem and sound tool choice matter more than familiarity with every technology listed.

What we offer

• Challenges that will help you grow and realise your potential really fast

• The opportunity to make a big impact — you'll build services used by millions of investors to build wealth

• Work with smart, spirited, helpful, high-performing colleagues with a common goal

• An environment where nothing is set in stone

• Appreciation for your talent and ideas

• A generous remuneration package, including annual bonuses

• An excellent social benefits package, including private health insurance, sports card and 25 days of paid vacation per year

• Delicious treats and a spacious game room

Bring your ambition to Europe's fastest-growing mobile broker!

What to expect

• Recruiter conversation

• Technical Interview

• Managerial interview

Your recruiter will explain each stage clearly and follow up after every conversation.

Bring your ambition to Europe’s fastest-growing mobile broker!

We thank all applicants, but only candidates selected for interview will be contacted. All personal data of applicants is protected by law and treated with strict confidentiality.