Senior Research Engineer - Learning to Rank

🏢 Summary: Senior Research Engineer role focused on designing, developing, and deploying production-ready machine learning models for search, ranking, and ads at scale. The position involves end-to-end ML ownership, from data exploration and experimentation to evaluation and production deployment, while translating state-of-the-art research into business impact. The role combines applied ML research with large-scale production collaboration. 🗂️ Requirements: Master’s or PhD in Machine Learning, Mathematics, Computer Science, Statistics, or related STEM field, Strong knowledge of deep learning techniques, Experience in at least one domain: Information Retrieval or Natural Language Processing, Ability to design and conduct scientific experiments using iterative methodologies, Experience working with complex, real-world datasets, Proficiency in Python, Experience with ML model development libraries (PyTorch or TensorFlow) 📃 Skills: Python, PyTorch, TensorFlow, Transformers, Pandas, NumPy, DeepLearning, NeuralNetworks, ContrastiveLearning, SemiSupervisedLearning, InformationRetrieval, NLP, LLMs, GCP, AWS, Azure, Kubernetes, Docker, Consul, GitHub, GitHubActions 🏢 Description: In the Learning to Rank team we develop machine learning models for search, ranking and ads. Our models serve millions of searches a day. We develop and apply state-of-the-art machine learning methods, helping Allegro grow and innovate with artificial intelligence. Beyond bringing AI to production, we are committed to advance the understanding of machine learning through open collaboration with the scientific community. About the role: As a Senior Research Engineer, you will work at the intersection of cutting-edge machine learning research and real-world products used at scale. You’ll take ownership of ML solutions end to end - from exploring complex data and selecting the right methods, to rigorous evaluation and production deployment. This role is for someone who enjoys navigating uncertainty, keeping pace with a fast-moving ML landscape, and turning research insights into tangible business impact, while also shaping ML expertise within the team and beyond. In your daily work you will handle the following tasks End-to-end ML ownership: Design and deliver production-ready machine learning solutions for Allegro products Data exploration: Analyze and understand complex data sets, identifying relevant data sources for ML use cases Model development & evaluation: Train, evaluate, and experiment with applied ML models using reliable evaluation methods Applied ML research: Translate state-of-the-art ML research into practical improvements for real-world solutions Tooling & methodology: Select ML tools and techniques that best fit concrete business needs Production collaboration: Work closely with cross-functional teams to deploy ML solutions into production Knowledge sharing: Spread ML expertise through internal sessions, presentations, and research activities Mentorship & expertise: Support junior team members and act as a trusted ML expert within the organization We are looking for people who Have a master's or PhD in machine learning, mathematics, computer science, statistics or other STEM fields Have a good knowledge of deep learning techniques (neural networks, contrastive learning, semi-supervised learning) in at least one domain (information retrieval, natural language generation or understanding, etc.) Know the methodology of conducting scientific research and the use of iterative processes of conducting experiments Have experience in working with real data that deviate from the standard, well-developed collections used in research Know Python and libraries necessary to work with model development (PyTorch, Tensorflow, Transformers, Pandas, Numpy, etc.) Nice-to-have: Understanding of Information Retrieval (IR) area Published research papers in ML-related topics Experience in business cooperation, deployments of ML-based solutions in commercial environments Prior experience in running large-scale computation on cloud platform (GCP, AWS or Azure) Prior experience in using LLMs for synthetic data generation/solving business problems What's in it 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. Long term discretionary incentive plan based on Allegro.eu shares (restricted stock units). Annual bonus based on your annual performance and company results. 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: Technical Team Leader role in the Recommendation team, combining hands-on development (20–50%) with leading a team delivering scalable, high-performance recommendation systems. The position focuses on designing and implementing distributed systems while ensuring engineering best practices and close collaboration with data and business teams. You will drive technical quality, architecture, and reliable delivery in a high-traffic environment. 🗂️ Requirements: Experience leading a development team as Tech Lead or Team Leader, Strong experience with Java, Kotlin or Scala, Active hands-on coding experience, Strong knowledge of testing, CI/CD and scalable architecture, Experience with high-traffic distributed systems, Experience in data engineering, Ability to ensure code quality through code reviews and TDD, Proficiency in English (B2+) 📃 Skills: Scala, Java, Kotlin, Python, SpringBoot, ApachePekko, ApacheSpark, GCP, Kubernetes, Docker, Consul, GitHub, GitHubActions, CICD, TDD, Microservices 🏢 Description: About the role 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 work 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 a leader who is still close to technology. In this role, you will spend around 20-50% of your time on technical work (coding, code reviews, architecture), with the remaining time focused on team development and business collaboration. Important things for you Contract of employment, tax-deductible costs Depending on your annual assessment and the company's results we offer: Annual bonus based on your annual performance and company results. Long term discretionary incentive plan based on Allegro.eu shares (restricted stock units). 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. Our team is based in Warsaw. What will you do? Lead the development team (5-7 members) – ensuring accurate, scalable, and reliable delivery predictions Technical leadership – mentoring, code reviews, ensuring high code quality Design and implementation of key systems (languages: Scala, Java/Kotlin, Python, stacks: Spring Boot, Apache Pekko, Apache Spark, Google Cloud Platform) Collaboration with cross-functional teams - data science, data engineering, analytics, UX, operations Ensuring high quality - clean code, code review, TDD, CI/CD to ensure the quality and maintainability Who are we looking for? Experience in leading a team (Java/Kotlin and/or Scala) as a Tech Lead or Team Leader Still actively coding and eager to maintain technical expertise Strong knowledge of engineering best practices (testing, CI/CD, scalable architecture) Experience with high-traffic distributed systems and data engineering Ability to bridge technical and business perspectives Proficiency in English (B2+) Nice to have Experience with ML Familiarity with GCP data engineering tools: BigQuery, Cloud Composer, Dataproc 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: Engineering role focused on designing, building, and optimizing AI-driven microservices that power a conversational marketplace assistant. The position involves LLM orchestration, Retrieval-Augmented Generation, semantic search, and high-performance retrieval in a cloud-native environment. You will own end-to-end development of AI services across Java/Kotlin and Python ecosystems, ensuring scalability, low latency, and high availability. 🗂️ Requirements: Proficiency in Python, Proficiency in Java, Proficiency in Kotlin, Experience with LLM orchestration, Experience with Retrieval-Augmented Generation (RAG), Experience with semantic search and vector search, Experience building microservices, Experience with cloud-native architectures, Ability to design and optimize high-availability systems, English level B2 or higher 📃 Skills: Python, Java, Kotlin, Spring, ADK, LangChain, Langfuse, LLM, RAG, LoRA, PEFT, AutoGen, CrewAI, Kubernetes, Docker, Consul, GitHub, GitHubActions, VectorSearch, Embeddings 🏢 Description: About the job: Performance & Scale: Design, build, and optimize AI-driven systems that process complex natural language interactions. Delivering low-latency, high-quality responses from our AI Assistant requires high-availability and smart optimization of LLM and retrieval workloads in practice. Modern Tech Stack: Work with a world-class, cloud-native polyglot environment. Our core backend technologies include Java , Kotlin , Spring, and ADK . At the same time, our AI and orchestration layer heavily relies on Python . You will utilize Python and LangChain for complex LLM orchestration, alongside Langfuse for observability, prompt tracking, and evaluation. We leverage advanced vector search and modern ML solutions to make our assistant truly smart. 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 AI microservices and data pipelines, from design to deployment; and improvements are dictated by results of our own experiments and AI evaluation metrics. Complex Challenges: From LLM orchestration and Retrieval-Augmented Generation (RAG) to semantic search optimization, you'll tackle the complex backend problems that power a conversational marketplace assistant. You will work across the Java/Kotlin and Python ecosystems, integrating advanced embedding models, prompt pipelines, and vector databases to ensure our AI deeply understands and accurately retrieves information. In our domain, we focus on delivering the core search and retrieval capabilities for the Allegro AI Assistant. We maintain a critical entry point for users looking to discover products, compare offers, and get personalized recommendations through natural conversations. Striving for relevancy and accuracy first, we are designing, implementing, and operating an extensive system combining modern microservice architecture with Large Language Models, high-performance retrievers, and vast data sources. We care about data quality, robust context building, and near real-time accuracy to best guide users through a highly dynamic marketplace via an intelligent, conversational interface. 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 14 200 - 20 200 Annual bonus based on your annual performance and company results. Our team is based in Poznań. We are looking for people who: Code in Python, Java and Kotlin ; 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 (Agent Development Kit, 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: The role focuses on designing, building, and optimizing AI-driven backend systems that power a large-scale conversational assistant with low-latency, high-availability requirements. You will work across Java/Kotlin and Python ecosystems to implement LLM orchestration, RAG pipelines, and semantic search solutions within a cloud-native microservices architecture. The position involves full ownership of AI microservices and data pipelines from design to deployment in a production-scale environment. 🗂️ Requirements: Proficiency in Python, Proficiency in Java, Proficiency in Kotlin, Experience with LLM orchestration and RAG, Experience with microservices architecture, Experience with vector search and semantic search, Experience with cloud-native environments, Ability to design and optimize high-availability, low-latency systems, English level B2 or higher 📃 Skills: Python, Java, Kotlin, Spring, ADK, LangChain, Langfuse, LLM, RAG, Kubernetes, Docker, Consul, GitHub, GitHubActions, VectorSearch, Microservices 🏢 Description: About the job: Performance & Scale: Design, build, and optimize AI-driven systems that process complex natural language interactions. Delivering low-latency, high-quality responses from our AI Assistant requires high-availability and smart optimization of LLM and retrieval workloads in practice. Modern Tech Stack: Work with a world-class, cloud-native polyglot environment. Our core backend technologies include Java , Kotlin , Spring, and ADK . At the same time, our AI and orchestration layer heavily relies on Python . You will utilize Python and LangChain for complex LLM orchestration, alongside Langfuse for observability, prompt tracking, and evaluation. We leverage advanced vector search and modern ML solutions to make our assistant truly smart. 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 AI microservices and data pipelines, from design to deployment; and improvements are dictated by results of our own experiments and AI evaluation metrics. Complex Challenges: From LLM orchestration and Retrieval-Augmented Generation (RAG) to semantic search optimization, you'll tackle the complex backend problems that power a conversational marketplace assistant. You will work across the Java/Kotlin and Python ecosystems, integrating advanced embedding models, prompt pipelines, and vector databases to ensure our AI deeply understands and accurately retrieves information. In our domain, we focus on delivering the core search and retrieval capabilities for the Allegro AI Assistant. We maintain a critical entry point for users looking to discover products, compare offers, and get personalized recommendations through natural conversations. Striving for relevancy and accuracy first, we are designing, implementing, and operating an extensive system combining modern microservice architecture with Large Language Models, high-performance retrievers, and vast data sources. We care about data quality, robust context building, and near real-time accuracy to best guide users through a highly dynamic marketplace via an intelligent, conversational interface. 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 14 600 - 20 825 Annual bonus based on your annual performance and company results. Our team is based in Poznań. We are looking for people who: Code in Python, Java and Kotlin ; 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 (Agent Development Kit, 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: Senior Software Engineer role focused on building and scaling high-impact SEO and AI-driven products, including a Market Trend Prediction engine powered by LLMs. The position involves leading technical decisions, designing big data systems at massive scale, and driving projects from PoC to production in a cloud-based microservices environment. 🗂️ Requirements: Proficiency in Kotlin or Java, Experience with microservices architecture, Experience with GCP or Azure, Experience designing high-scale distributed systems, Experience with Big Data processing and analytics, Experience integrating LLMs or AI solutions into production systems, Fluent Polish (C1), English (B2 or higher) 📃 Skills: Kotlin, Java, Microservices, GCP, Azure, BigQuery, Airflow, Scala, Kubernetes, Docker, Consul, GitHub, GitHubActions, LLM, LangChain, AutoGen, LoRA, PEFT 🏢 Description: About the Team: SEOzord Team The SEOzord Team is the technical powerhouse behind Allegro’s SEO business unit. We are a specialized engineering squad (7 Developers, Product Manager and Leader) responsible for one of the largest traffic entry points on the Polish internet. We don't just maintain, we innovate. Last year, we launched Allegro Rankings, a product now scaling internationally. Currently, we are embarking on a high-impact mission: building a Market Trend Prediction engine using Large Language Models (LLMs). This is a rare opportunity to shape the architectural foundations of a project that turns AI experiments into production-grade business solutions Your main responsibilities: As a Senior Software Engineer, you will have the autonomy to drive technical decisions and lead the team through the complete lifecycle of complex products - from initial PoC to petabyte-scale production. Your main focus areas: Engineering Excellence: Leading by example through mentorship, high-quality code reviews, and establishing engineering standards. Big Data at Scale: Designing and optimizing systems that handle massive daily request volumes and extract actionable insights from vast datasets. AI Integration: Leading the technical integration of LLMs to drive our predictive capabilities. We are looking for people who: Tech Stack: You are proficient in Kotlin or Java and have a solid foundation in microservices and cloud environments (GCP/Azure). Ownership: You feel comfortable interacting with stakeholders and taking full end-to-end ownership—from requirements to post-deployment monitoring. Big Data Ambitions: You want to work with tools like BigQuery and Airflow. Experience with Scala is a significant plus. AI Curiosity (Nice to have): Familiarity with LLM tuning (LoRA, PEFT) or frameworks like LangChain/AutoGen will help you lead our newest initiatives. Language: You are fluent in Polish (C1) and English (min. B2) . Note: As our current workflow is linguistically homogeneous, Polish is a must-have for this role. What's in it 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): 18 850 - 25 900 gross Annual bonus based on your annual performance and company results. 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: Senior Software Engineer role focused on leading architecture and development of large-scale SEO and AI-driven systems, including a Market Trend Prediction engine based on LLMs. The position combines technical leadership, big data engineering, and cloud-based microservices development from PoC to production at petabyte scale. The role requires strong ownership, cross-team collaboration, and hands-on system design in a high-traffic environment. 🗂️ Requirements: Proficiency in Kotlin or Java, Experience with microservices architecture, Experience with cloud environments (GCP or Azure), Experience designing and optimizing large-scale data systems, Ability to lead technical architecture and make end-to-end technical decisions, Experience with Big Data tools such as BigQuery and Airflow, Fluent Polish (C1), English proficiency minimum B2 📃 Skills: Kotlin, Java, Microservices, GCP, Azure, BigQuery, Airflow, Scala, LLM, LoRA, PEFT, LangChain, AutoGen, Kubernetes, Docker, Consul, GitHub, GitHubActions 🏢 Description: About the Team: Chonk Team The Chonk Team is the technical powerhouse behind Allegro’s SEO business unit. We are a specialized engineering squad (4 Developers, Project Manager, and Leader) responsible for one of the largest traffic entry points on the Polish internet. We don't just maintain; we innovate. Last year, we launched Allegro Rankings, a product now scaling internationally. Currently, we are embarking on a high-impact mission: building a Market Trend Prediction engine using Large Language Models (LLMs). This is a rare opportunity to shape the architectural foundations of a project that turns AI experiments into production-grade business solutions Your main responsibilities: As a Senior Software Engineer, you will act as a Technical Leader and architect for the SEO business area. You will have the autonomy to drive technical decisions and lead the team through the complete lifecycle of complex products—from initial PoC to petabyte-scale production. Your main focus areas: Engineering Excellence: Leading by example through mentorship, high-quality code reviews, and establishing engineering standards. Big Data at Scale: Designing and optimizing systems that handle massive daily request volumes and extract actionable insights from vast datasets. AI Integration: Leading the technical integration of LLMs to drive our predictive capabilities. Cross-team Orchestration: Collaborating with over a dozen teams (Offer, Product, Listing, Category) to manage complex technical dependencies. We are looking for people who: Tech Stack: You are proficient in Kotlin or Java and have a solid foundation in microservices and cloud environments (GCP/Azure). Ownership: You feel comfortable interacting with stakeholders and taking full end-to-end ownership—from requirements to post-deployment monitoring. Big Data Ambitions: You want to work with tools like BigQuery and Airflow. Experience with Scala is a significant plus. AI Curiosity (Nice to have): Familiarity with LLM tuning (LoRA, PEFT) or frameworks like LangChain/AutoGen will help you lead our newest initiatives. Language: You are fluent in Polish (C1) and English (min. B2) . Note: As our current workflow is linguistically homogeneous, Polish is a must-have for this role. What's in it 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): 18 850 - 25 900 gross Annual bonus based on your annual performance and company results. 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: Technical role focused on designing and optimizing AI-driven backend systems for a conversational marketplace assistant, with strong emphasis on LLM orchestration, Retrieval-Augmented Generation, and semantic search. The position involves building and operating high-availability Python-based AI microservices integrated with Java/Kotlin services in a cloud-native environment. You will own end-to-end development of scalable, low-latency AI solutions leveraging modern ML and vector search technologies. 🗂️ Requirements: Proficiency in Python, Proficiency in Java, Proficiency in Kotlin, Experience with LLM orchestration, Experience with Retrieval-Augmented Generation (RAG), Experience with semantic search optimization, Ability to build and maintain microservices, Experience with cloud-native environments, Experience with vector databases and embedding models, English level B2 or higher 📃 Skills: Python, Java, Kotlin, Spring, LangChain, Langfuse, LLM, RAG, VectorSearch, Embeddings, Kubernetes, Docker, Consul, GitHub, GitHubActions, Microservices, SemanticSearch 🏢 Description: Software Engineer 2 (Python) Location: Poznań, PL, 61-569 Company: Allegro sp. z o.o. Team: Technology Contract Type: Employee About the job: Performance & Scale: Design, build, and optimize AI-driven systems that process complex natural language interactions. Delivering low-latency, high-quality responses from our AI Assistant requires high-availability and smart optimization of LLM and retrieval workloads in practice. Modern Tech Stack: Work with a world-class, cloud-native polyglot environment. Our core backend technologies include Java , Kotlin , Spring, and ADK . At the same time, our AI and orchestration layer heavily relies on Python . You will utilize Python and LangChain for complex LLM orchestration, alongside Langfuse for observability, prompt tracking, and evaluation. We leverage advanced vector search and modern ML solutions to make our assistant truly smart. 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 AI microservices and data pipelines, from design to deployment; and improvements are dictated by results of our own experiments and AI evaluation metrics. Complex Challenges: From LLM orchestration and Retrieval-Augmented Generation (RAG) to semantic search optimization, you'll tackle the complex backend problems that power a conversational marketplace assistant. You will work across the Java/Kotlin and Python ecosystems, integrating advanced embedding models, prompt pipelines, and vector databases to ensure our AI deeply understands and accurately retrieves information. In our domain, we focus on delivering the core search and retrieval capabilities for the Allegro AI Assistant. We maintain a critical entry point for users looking to discover products, compare offers, and get personalized recommendations through natural conversations. Striving for relevancy and accuracy first, we are designing, implementing, and operating an extensive system combining modern microservice architecture with Large Language Models, high-performance retrievers, and vast data sources. We care about data quality, robust context building, and near real-time accuracy to best guide users through a highly dynamic marketplace via an intelligent, conversational interface. 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 14 200 - 20 200 Annual bonus based on your annual performance and company results. Our team is based in Poznań. We are looking for people who: Code in Python, Java and Kotlin ; 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 (Agent Development Kit, 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 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!