Senior Software Engineer (Java/Kotlin)

Allegro Ltd.; Polska; Hybrid; PLN 210,000 - 289,000; Full time

Benefits offered by this job

Hybrid work model

Well-located offices & facilities

MacBook Pro / equipment

Fringe benefits cafeteria plan

English language courses

Volunteer day

Job summary

Allegro Ltd. in Warsaw is seeking backend engineers to build high-throughput services in Kotlin and Java, with a focus on API management, security, and AI-assisted tooling.

You will join Allegro Tech, work in a hybrid setup (4/1) with flexible hours, modern tech stack (Kubernetes, Docker, BigQuery), and opportunities to grow your skills while delivering impactful products for millions of customers. The role also offers a competitive PLN salary, annual bonus, RSUs, volunteering days, and a

Qualifications

• Commercial experience coding in Kotlin or Java.
• Value high-quality code and engineering best practices to solve complex challenges in distributed systems.
• Excited to find new ways of using AI in daily work.
• Embrace a growth mindset, value team stability, and are open to occasionally picking up frontend tasks.
• Communicate effectively in Polish and English (at least a B2 level).

Responsibilities

• Design and implement high-throughput backend services with a strict 50 ms time budget.
• Develop API management and security tooling for platform compliance.
• Collaborate with Data Scientists and ML Engineers to automate processes and decisions.

Skills

Kotlin

Java

React

Tools

Kubernetes

Docker

Consul

GitHub

GitHub Actions

Job description

• Low Latency & Massive Scale:Work on high-throughput systems handling massive API traffic with a strict 50 ms time budget. Expect deep technical challenges.
• API Security & Abuse Detection: Design and build essential tools for API management, key and resource access control, continuous abusive traffic detection, and mitigation to ensure platform compliance.
• Modern Tech Stack & Big Data: Develop high-performance backend microservices using Kotlin and Java while leveraging GCP big data pipelines (BigQuery, Airflow) and advanced AI tools.

Join the API Management team! You will have the opportunity to build tools that protect our platform's API. The team collaborates closely with Data Scientists and ML Engineers to automate key processes and decision-making. You can expect high-performance technical challenges, an emphasis on engineering best practices, continuous opportunities to expand your knowledge, and a supportive, collaborative atmosphere.

Important things for you:

• Flexible working hours in the hybrid model (4/1) - working hours start between 7:00 a.m. and 10:00 a.m. We also have 30 days of occasional remote work.
• The salary range for this position depending on the skill set is as follows (contract of employment, tax-deductible cost):
  • PLN 18 850 - 25 900
  • Annual bonus based on your annual performance and company results.
  • Long-term discretionary incentive plan based on Allegro.eu shares (restricted stock units).
• Our team is based in Warsaw.

We are looking for people who:

Have commercial experience coding in Kotlin or Java (with an eagerness to master Kotlin for our new services);

Value high-quality code and engineering best practices to solve complex challenges in massive-scale distributed systems;

Are excited to find new ways of using AI in daily work;

Embrace a growth mindset, value team stability, and are open to occasionally picking up frontend tasks (React is a nice-to-have);

Communicate effectively in Polish and English (at least a B2 level).

What's in it for you:

• Well-located offices (with e.g. fully equipped kitchens, bicycle parking, terraces full of greenery) and excellent work tools (e.g., raised desks, ergonomic chairs, interactive conference rooms).
• A 16\" or 14\" MacBook Pro or corresponding Dell with Windows (if you don't like Macs) and all the necessary accessories.
• A wide selection of fringe benefits in a cafeteria plan - you choose what you like (e.g., medical, sports or lunch packages, insurance, purchase vouchers).
• English classes that we pay for related to the specific nature of your job.
• A training budget, inter-team tourism (see more here), hackathons, and an internal learning platform where you will find multiple trainings.
• An additional day off for volunteering, which you can use alone, with a team, or with a larger group of people connected by a common goal.
• Social events for Allegro people - Spin Kilometers, Family Day, Fat Thursday, Advent of Code, and many other occasions we enjoy.

And that's just the beginning! You can read more about the benefits here .

#goodtobehere means that:

• You will join a team you can count on - we work with top-class specialists who have knowledge- and experience-sharing in their DNA.
• You will love our level of autonomy in team organization, the space for continuous development, and the opportunity to try new things. You get to choose which technology solves the problem and you are responsible for what you create.
• You will value our Developer Experience and the full platform of tools and technologies that make creating software easier. We rely on an internal ecosystem based on self-service and widely used tools such as Kubernetes, Docker, Consul, GitHub, and GitHub Actions. Thanks to this, you can contribute to Allegro from your very first days on the job.
• You will be equipped with modern AI tools to automate repetitive tasks, allowing you to focus on developing new services and refining existing ones (also leveraging AI support).
• You will create solutions that will be used (and loved!) by your friends, family and millions of our customers.
• You will meet the Allegro Scale, which starts with over 1000 microservices, an open-source data bus (Hermes) with 300K+ rps, a Service Mesh with 1M+ rps, tens of petabytes of data, and production-used machine learning.
• You will become part of Allegro Tech - we speak at industry conferences, cooperate with tech communities, run our own blog (it's been over 10 years!), record podcasts, lead guilds, and we organize our own internal conference - the Allegro Tech Meeting. We create solutions we love (and can) to talk about!