Software Engineer 1 (Java / Kotlin)

🏢 Summary: Backend engineering role focused on designing and operating high-availability microservices at massive scale within a cloud-native environment. The position involves building AI-driven pipelines and distributed systems that ensure product catalog quality in a real-time marketplace. You will own services end-to-end, working with Kotlin/Java, streaming technologies, and Kubernetes in an autonomous, agile team. 🗂️ Requirements: Proficiency in Kotlin or Java, Experience with distributed systems and microservices architecture, Experience with data streaming systems, Ability to design high-availability and high-performance systems, Experience with cloud-native environments, English B2 level minimum, Polish B2 level minimum 📃 Skills: Kotlin, Java, Spring, Kafka, Kubernetes, Docker, Consul, GitHub, GitHubActions, Microservices, LLM, MachineLearning 🏢 Description: About the job: Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. Our team owns the quality of product content in Allegro's product catalog — names, descriptions, and the processes that keep them correct at scale. We build AI-driven pipelines (including LLM-based evaluation and generation) that automatically maintain content quality, and we run A/B experiments to prove when catalog data is ready to replace merchant-provided content on the buyer path. We work in a cross-functional setup with backend engineers, a product manager, and close collaboration with data analysts and quality specialists. 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 11 200 - 15 250 Annual bonus based on your annual performance and company results. Our team is based in Toruń. We are looking for people who: Code in Kotlin or Java ; Expect work that has a deeper meaning (not only tasks "management has commissioned") and want to enjoy its results; Want to be proud of the code they create. They eagerly accept comments and share knowledge during code reviews; Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Are proactive and positive — you'll join people who actually like collaborating; Know English and Polish at at least 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend Engineer role focused on building and operating high-availability, high-performance microservices in a large-scale, real-time marketplace. The position involves designing distributed systems, data streaming solutions, and AI-driven content quality pipelines using a modern cloud-native stack. You will own services end-to-end in an autonomous team following a "you build it, you run it" approach. 🗂️ Requirements: Proficiency in Kotlin or Java, Experience building high-availability, high-performance backend systems, Experience with distributed systems and microservices architecture, Experience with data streaming systems, Experience working in cloud-native environments, Ability to design, deploy, and operate services in production, Experience with AI/ML-driven pipelines, English B2 level minimum, Polish B2 level minimum 📃 Skills: Kotlin, Java, Spring, Kafka, Kubernetes, Docker, Consul, GitHub, GitHubActions, Microservices, DistributedSystems, DataStreaming, MachineLearning, LLM, A/BTesting, ServiceMesh, Cloud, Hermes 🏢 Description: About the job: Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. Our team owns the quality of product content in Allegro's product catalog — names, descriptions, and the processes that keep them correct at scale. We build AI-driven pipelines (including LLM-based evaluation and generation) that automatically maintain content quality, and we run A/B experiments to prove when catalog data is ready to replace merchant-provided content on the buyer path. We work in a cross-functional setup with backend engineers, a product manager, and close collaboration with data analysts and quality specialists. 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 11 200 - 15 250 Annual bonus based on your annual performance and company results. Our team is based in Toruń. We are looking for people who: Code in Kotlin or Java ; Expect work that has a deeper meaning (not only tasks "management has commissioned") and want to enjoy its results; Want to be proud of the code they create. They eagerly accept comments and share knowledge during code reviews; Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Are proactive and positive — you'll join people who actually like collaborating; Know English and Polish at at least 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend engineering role focused on designing and operating high-availability, large-scale microservices in a cloud-native environment using Kotlin and modern distributed systems technologies. The position involves full ownership of services, building real-time systems, data streaming solutions, and AI-powered customer experience products. Engineers work on complex backend challenges within a highly autonomous, agile team. 🗂️ Requirements: Proficiency in Kotlin or Java, Willingness to develop in Kotlin in greenfield projects, Experience building high-availability and high-performance systems, Experience with distributed systems and microservices architecture, Ability to design, build, deploy, and operate services end-to-end, Experience with data streaming systems, English level B2 or higher 📃 Skills: Kotlin, Java, Spring, Kafka, Kubernetes, Docker, Consul, GitHub, GitHubActions, Microservices, DistributedSystems, DataStreaming, MachineLearning, AI 🏢 Description: About the job Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. In our Customer Experience (CX) domain, we focus on creating a seamless and intuitive contact journey for our users. Our mission is to elevate the support experience by developing the core contact path, integrating diverse communication channels, and implementing our cutting-edge AI Assistant to provide smart, instant resolutions. We also own and manage the platform's central survey engine, which empowers the business to gather crucial user feedback and continuously shape our strategy. We take full end-to-end ownership of our products, allowing us to build scalable, high-performing systems that directly impact user satisfaction and adapt to evolving business needs. We work in cross-functional teams where diverse technologies converge to drive Allegro’s success. Our team consists of backend and frontend specialists, collaborating closely with Product Managers, UX Designers, and AI/Data specialists. 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 10 700 - 14 900 Annual bonus based on your annual performance and company results. Our team is based in Warsaw. We are looking for people who: Code in Kotlin or Java and are eager to master Kotlin by taking part greenfield project Want to be proud of the code they create ; they value high-quality code reviews and engage in substantive discussions on software engineering best practices; Are excited about building new products and want to experience the journey of launching a fresh project within the Allegro ecosystem; Are open to developing soft skills and exploring a full-stack mindset by learning new backend, frontend, and mobile technologies; Are open to incorporating AI coding assistants into their daily work to maximize efficiency and focus on complex problem-solving Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Know English at at least 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend Engineer role focused on designing and operating high-availability, high-performance microservices in a massive-scale, cloud-native environment. The position involves building distributed systems and real-time data solutions using Java/Kotlin and modern technologies on GCP. You will own services end-to-end in an autonomous team following a "you build it, you run it" approach. 🗂️ Requirements: Proficiency in Java or Kotlin, Willingness to develop in Kotlin, Experience with microservices architecture, Experience with distributed systems, Experience with cloud environments (GCP), Knowledge of Spring framework, Experience with databases (NoSQL), Ability to work with high-load systems, English level B2 or higher 📃 Skills: Java, Kotlin, Spring, MongoDB, GCP, Microservices, React, Airflow, BigQuery, Kubernetes, Docker, Consul, GitHub, GitHubActions 🏢 Description: About the job Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment (GCP). Our core technologies include Java, Kotlin, Spring, MongoDB, microservices, React, Airflow (BigData). True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. About us We are the team behind Allegro Prices - one of our most important pricing programs. As part of the Competitive Price unit, we build its logic and grow its reach to keep our prices competitive. Our main goal is to ensure great deals on the products that shoppers actually look for. We do this at scale using full automation and data from many different sources Important things for you Flexible working hours in the hybrid model (4/1) - working hours start between 7:00 a.m. and 09:30 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 10 700 - 14 900 Annual bonus based on your annual performance and company results. Our team is based in Kraków and Warsaw. We are looking for people who: Code in Kotlin or Java and are eager to master Kotlin by taking part greenfield project Have a natural curiosity for new technologies and a desire to become a well-rounded engineer by exploring our modern stack, including React, Airflow and BigQuery; Want to be proud of the code they create ; they value high-quality code reviews and engage in substantive discussions on software engineering best practices; Are excited about building new products and want to experience the journey of launching a fresh project within the Allegro ecosystem; Are open to developing soft skills and exploring a full-stack mindset by learning new backend and frontend Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Know English at at least 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend engineering role in the Recommendation team focused on building and operating high-scale, high-availability microservices and ML-serving infrastructure in a cloud-native environment. The position involves designing distributed systems, data streaming solutions, and end-to-end ML systems that power real-time personalized recommendations. You will own services from design to deployment using modern technologies such as Kotlin, Spring, Kafka, Kubernetes, BigQuery, and Spark. 🗂️ Requirements: Proficiency in Kotlin or Java, Willingness to develop in Kotlin on greenfield projects, Experience with distributed systems and microservices architecture, Experience with cloud-native technologies and containerization, Ability to design high-availability and high-performance systems, Experience with data processing or data streaming systems, Understanding of ML model serving concepts, Experience with BigQuery or Apache Spark for data processing, English proficiency at B2 level or higher 📃 Skills: Kotlin, Java, Spring, Kafka, Kubernetes, Docker, Consul, GitHub, GitHubActions, BigQuery, Spark, Python, VectorSearch, Microservices, ML, Hermes 🏢 Description: About the job Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. End-to-End ML Systems: Bridge the gap between big data and real-time product impact. You’ll build the infrastructure for serving ML models , using BigQuery and Apache Spark for offline data processing and Vector Search databases for high-speed retrieval. You’ll integrate these components with our microservices architecture to create the sophisticated recommendation systems that power a personalized user experience. Join the Recommendation team! You will have a chance to build tools for recommendations on Allegro - one of the most visible products on the platform. Your team works closely with the Machine Learning team, creating the best experience for customers. High performance, engineering best practices and great atmosphere in the team guaranteed! 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 11 200 - 15 250 Annual bonus based on your annual performance and company results. Our team is based in Warsaw. We are looking for people who Code in Kotlin or Java and are eager to master Kotlin by taking part greenfield project Want to be proud of the code they create ; they value high-quality code reviews and engage in substantive discussions on software engineering best practices; Are excited about building new products and want to experience the journey of launching a fresh project within the Allegro ecosystem; Are open to developing soft skills and exploring a full-stack mindset by learning new backend, frontend, and mobile technologies; Are open to incorporating AI coding assistants into their daily work to maximize efficiency and focus on complex problem-solving Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Know English at at least B2 level; Are eager to dive into the world of ML Engineering , learning how to serve ML models (using Python) and handle large-scale offline data processing using tools like BigQuery or Apache Spark. 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend Engineer role in the Advertising team focused on building and operating high-scale, cloud-native systems and end-to-end ML infrastructure for a real-time marketplace. The position involves developing microservices, data pipelines, and advertising systems using Kotlin/Scala, Spring, Kafka, and big data technologies. You will own services end-to-end in a high-availability environment handling massive traffic and complex distributed challenges. 🗂️ Requirements: Proficiency in Kotlin or Scala, Experience with Spring Boot, Experience with Kafka, Hands-on experience with Apache Airflow, Hands-on experience with Apache Spark, Proficiency in PostgreSQL, Experience with database migrations, Experience designing and integrating APIs, English level B2 or higher 📃 Skills: Kotlin, Scala, Spring, SpringBoot, Kafka, Airflow, Spark, PostgreSQL, BigQuery, Kubernetes, Docker, Consul, GitHub, GitHubActions, React, TypeScript 🏢 Description: About the job Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. End-to-End ML Systems: Bridge the gap between big data and real-time product impact. You’ll build the infrastructure using BigQuery and Apache Spark for offline data processing. You’ll integrate these components with our microservices architecture to create the sophisticated advertising system that powers a personalized user experience. Join the Advertising team! You will have a chance to build Allegro Ads - one of the most visible products on the platform. Your team works closely with the Machine Learning team, creating the best experience for customers. High performance, engineering best practices and great atmosphere in the team guaranteed! 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. Our team is based in Warsaw. We are looking for people who: Code in Kotlin or Scala and have experience with Spring Boot and Kafka to build robust backend systems; Have hands-on experience with Apache Airflow and Spark , enabling them to manage high-velocity data pipelines and build scalable reporting engines; Are proficient in PostgreSQL and have experience with database migrations and designing integrations via APIs; Enjoy close collaboration with Data Scientists and Analysts, working together to implement complex models and turn raw data into actionable insights; Are enthusiastic about AI and want to stay at the forefront of technical innovation; Want to build impactful tools for a diverse range of users, helping them understand campaign performance through advanced statistics and dashboards; Experience with frontend technologies (React/TypeScript) is a “Nice to have” to help build modern frontend reporting components; Are excited to join a growing team where they can influence the technical vision and help shape new projects from the ground up within the ecosystem; Know English at at least 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend engineer role in a large-scale online payments ecosystem, building and operating high-availability microservices in a cloud-native environment. The position focuses on designing, optimizing, and maintaining distributed systems that power real-time payment solutions and integrations with major payment operators. You will work with modern technologies, own services end-to-end, and solve complex challenges related to scalability, performance, and secure payment processing. 🗂️ Requirements: Proficiency in Kotlin or Java, Willingness to develop expertise in Kotlin, Experience building backend systems, Understanding of distributed systems, Ability to design and optimize high-performance services, English at B2 level or higher 📃 Skills: Kotlin, Java, Spring, Kafka, Kubernetes, Docker, Consul, GitHub, GitHubActions, Microservices, DistributedSystems, DataStreaming, MachineLearning 🏢 Description: About the job: Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. In our department, we focus on online payments. We are building an ecosystem that enables secure, easy, fast, and convenient payments for buyers. We also take care of the seller's side, ensuring they can issue quick refunds or pay their Allegro billing. We provide a range of payment solutions, from bank transfers and BLIK to card payments, Apple Pay, Google Pay, installment products, and many others. In our team, we are directly responsible for integration with payment operators such as PayU and P24, and we cooperate with entities such as BLIK, Visa, and Mastercard. If you want to find out which method buyers use most often, what their biggest problem is when paying, how to securely store payment card data, or how Apple Pay, Google Pay, and BLIK without a code work behind the scenes, join us. 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 11 200 - 15 250 Annual bonus based on your annual performance and company results. Our team is based in Poznań. We are looking for people who: Code in Kotlin or Java and are eager to master Kotlin by taking part in greenfield projects Expect work that has a deeper meaning (not only tasks "management has commissioned") and want to enjoy its results; Want to be proud of the code they create; they value high-quality code reviews and engage in substantive discussions on software engineering best practices; Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Know English at at least B2 level; Have the nature of an explorer. You are not satisfied with superficial answers - you like to "break a problem down into its prime factors" until you understand how something works underneath. Treat learning as a process, not an unpleasant chore. The world of payments is changing dynamically, and you want to stay up to date with every innovation. Are a "driver," not a passenger. See room for improvement? You don't wait for a command; you take the initiative and act. 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! Send us your CV and… see you at Allegro!

🏢 Summary: Design and develop high-performance, cloud-native backend systems powering large-scale search and recommendation services. Work in an autonomous team owning microservices end-to-end in a distributed, real-time marketplace environment. Solve complex challenges in data streaming, search optimization, and machine learning at massive scale. 🗂️ Requirements: Proficiency in Kotlin or Java, Experience with backend development, Understanding of distributed systems, Experience with microservices architecture, Ability to design high-performance systems, English B2 level or higher, Participation in code reviews, Ownership of services from design to deployment 📃 Skills: Java, Kotlin, Spring, Kafka, Kubernetes, Vespa, Lucene, Solr, Docker, Consul, GitHub, GitHubActions, Microservices, DistributedSystems, MachineLearning, LLM, LoRA, PEFT, LangChain, AutoGen, CrewAI 🏢 Description: Senior Software Engineer (Java / Kotlin) Location: Poznań, PL, 61-569 Company: Allegro sp. z o.o. Team: Technology Contract Type: Employee About the job Massive Scale : Design, build, and optimize systems that handle thousands of requests per second. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. On the back side, there is Vespa and a highly optimized and heavily customized Lucene/Solr installation. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment; and improvements are dictated by results of our own experiments. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. And a constantly modernizing approach to search solutions will give you the opportunity to work with advanced embedding and ranking models and pipelines. In our domain we focus on delivering search results for multiple Allegro services, from search result pages, to recommendations, to offers comparisons in various placements. We maintain a critical entry point for users’ search experience through a huge catalog of products and offers, striving for relevancy first. To deliver, we are designing, implementing and operating an extensive system combining modern microservice architecture with high performance backends and vast data sources. We care about data quality and availability and strive for near real-time accuracy, to best guide users to products and offers in a highly dynamic marketplace. 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 18 400 - 25 450 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 Poznań. We are looking for people who: Code in Kotlin or Java ; Expect work that requires creative approach to search experience challenges, to be proud of enjoying its results together with all Allegro users; Want to create solid code, eagerly accept comments and share knowledge during code reviews; Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Know English at at least B2 level. Nice to have: You are open to diverse technologies and workflows, including dev-operational tools on one hand, and working with data on the other. Basic experience with LLM tuning (LoRA, PEFT), training and evaluation pipelines for models and/or basic frameworks for building AI Agents (LangChain, AutoGen, CrewAI) would be great! 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend Engineer role in the Advertising team focused on building and operating high-availability, large-scale microservices and ML-powered systems. The position involves designing and optimizing distributed systems using a modern cloud-native stack (Kotlin, Spring, Kafka, Kubernetes) and integrating big data and machine learning components into a real-time marketplace. The offer includes hybrid work, competitive salary, annual bonus, and strong ownership within an autonomous agile team. 🗂️ Requirements: Proficiency in Kotlin or Java, Willingness to work with Kotlin in greenfield projects, Experience with backend development and microservices, Ability to design and optimize high-performance, distributed systems, Experience with cloud-native technologies, Understanding of data processing and system integration, English proficiency at B2 level or higher 📃 Skills: Kotlin, Java, Spring, Kafka, Kubernetes, BigQuery, Spark, Docker, Consul, GitHub, GitHubActions, MachineLearning, Microservices 🏢 Description: 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 11 200 - 15 250 Annual bonus based on your annual performance and company results. Our team is based in Poznań. About the job Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. End-to-End ML Systems: Bridge the gap between big data and real-time product impact. You’ll build the infrastructure for serving ML models , using BigQuery and Apache Spark for offline data processing. You’ll integrate these components with our microservices architecture to create the sophisticated advertising system that powers a personalized user experience. Join the Advertising team! You will have a chance to build Allegro Ads - one of the most visible products on the platform. Your team works closely with the Machine Learning team, creating the best experience for customers. High performance, engineering best practices and great atmosphere in the team guaranteed! We are looking for people who: Code in Kotlin or Java and are eager to master Kotlin by taking part greenfield project Want to be proud of the code they create ; they value high-quality code reviews and engage in substantive discussions on software engineering best practices; Are excited about building new products and want to experience the journey of launching a fresh project within the Allegro ecosystem; Are open to developing soft skills and embracing a growth mindset through active participation in code reviews, pair programming, and team retrospectives.; Are open to incorporating AI coding assistants into their daily work to maximize efficiency and focus on complex problem-solving Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Know English at at least 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! Send us your CV and… see you at Allegro!

🏢 Summary: Backend engineering role focused on building and operating high‑availability, large‑scale advertising systems in a cloud‑native environment. The position involves designing microservices, integrating ML infrastructure, and processing real‑time and offline data using modern technologies. You will own services end‑to‑end in a distributed, high‑performance ecosystem. 🗂️ Requirements: Proficiency in Kotlin or Java, Experience building microservices, Experience with distributed systems, Experience with high‑performance and high‑availability systems, Experience with data streaming systems, Experience with cloud‑native architectures, Experience integrating ML models into backend systems, Experience with BigQuery and Apache Spark, Ability to work with Kubernetes-based environments, English level B2 or higher 📃 Skills: Kotlin, Java, Spring, Kafka, Kubernetes, Docker, Consul, GitHub, GitHubActions, BigQuery, Spark, Microservices, ML, Hermes 🏢 Description: 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 11 200 - 15 250 Annual bonus based on your annual performance and company results. Our team is based in Poznań. About the job Massive Scale : Design, build, and optimize systems that handle thousands of requests per minute. This is high-availability, high-performance engineering in practice. Modern Tech Stack : Work with a world-class, cloud-native environment. Our core technologies include Kotlin, Spring, Kafka, and Kubernetes. We're not shy when it comes to ML too :) True Ownership & Autonomy : We live by a "you build it, you run it" philosophy. You'll join an agile, autonomous team with full ownership of your microservices, from design to deployment. Complex Challenges : From distributed systems and data streaming to algorithmic optimization, you'll tackle the complex backend problems that power a massive, real-time marketplace. End-to-End ML Systems: Bridge the gap between big data and real-time product impact. You’ll build the infrastructure for serving ML models , using BigQuery and Apache Spark for offline data processing. You’ll integrate these components with our microservices architecture to create the sophisticated advertising system that powers a personalized user experience. Join the Advertising team! You will have a chance to build Allegro Ads - one of the most visible products on the platform. Your team works closely with the Machine Learning team, creating the best experience for customers. High performance, engineering best practices and great atmosphere in the team guaranteed! We are looking for people who: Code in Kotlin or Java and are eager to master Kotlin by taking part greenfield project Want to be proud of the code they create ; they value high-quality code reviews and engage in substantive discussions on software engineering best practices; Are excited about building new products and want to experience the journey of launching a fresh project within the Allegro ecosystem; Are open to developing soft skills and embracing a growth mindset through active participation in code reviews, pair programming, and team retrospectives.; Are open to incorporating AI coding assistants into their daily work to maximize efficiency and focus on complex problem-solving Can look for effective solutions to the requirements set by users; Want to constantly develop and update their knowledge; Know English at at least 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! Send us your CV and… see you at Allegro!