Intern/ Junior Python Developer

🏢 Summary: Entry-level Backend Engineer role focused on supporting the development of backend services and REST APIs under senior guidance. The position involves contributing to production systems, writing tested and maintainable code, and collaborating within a cross-functional engineering team. Ideal for candidates with foundational Java experience seeking hands-on experience in scalable and secure systems. 🗂️ Requirements: Bachelor's degree in Computer Science or related field (or currently pursuing), Minimum 0.5 years of Java experience, Practical experience with RESTful APIs, Ability to work with HTTP methods, status codes, and JSON, Experience writing SQL queries (SELECT, JOIN, WHERE, GROUP BY) or using ORM, Basic understanding of SQL and NoSQL differences, Knowledge of data structures and algorithms, Ability to use Git in a team environment (branching, pull requests, merge conflicts), Experience writing unit tests, Experience contributing code to production through review and deployment process 📃 Skills: Java, REST, HTTP, JSON, SQL, NoSQL, ORM, Git, JUnit, Pytest, Jest, CI, Algorithms, DataStructures, APIs, Testing 🏢 Description: (5190) About This Role You will be a part of the Engineering team and reports to our Manager, Engineering. You will support the development of backend services and APIs that power customer’s products. Working under close guidance from experienced engineers, you will gain hands-on experience contributing to real-world systems while learning best practices in software development, scalability, and security. Key Responsibilities Support the development of backend services and APIs under direct supervision of senior engineers Assist with writing clean, maintainable, and well-documented code following team standards Help debug, test, and troubleshoot backend systems and services Contribute to small tasks or components within larger projects Collaborate with cross-functional teams including Frontend, Product, and DevOps Participate in code reviews and apply feedback to improve technical skills Assist in writing unit tests and validating functionality Document technical processes and development work Required Qualifications Bachelor's degree in Computer Science or a related field; Currently pursuing is also an option Strong theoretical knowledge of Java, at least 0.5 years of experience Practical experience building and consuming RESTful APIs — HTTP methods, status codes, JSON, request/response handling, basic error handling. Working knowledge of databases — has written real SQL queries (SELECT, JOIN, WHERE, GROUP BY) or used an ORM in production code; understands the difference between SQL and NoSQL at a basic level. Solid understanding of data structures and algorithms — arrays, hash maps, trees, basic Big-O analysis — sufficient to discuss simple coding problems and reason about correctness. Comfortable with Git in a team setting — branching, pull requests, code review, addressing feedback, resolving merge conflicts; has worked in a shared repository with at least one other developer. Hands-on experience writing unit tests for their own code (pytest, JUnit, Jest, or equivalent), and basic familiarity with how testing fits into a CI pipeline. Demonstrated ability to ship code to production — even small features or bug fixes — through a real review and deployment process; ability to clearly describe what they built, how it was reviewed, and how it was tested. Genuine interest in cryptocurrency, blockchain, or Web3 (self-taught is fine — owning crypto, reading, side projects, hackathons) and willingness to learn the regulated FinTech context; English level: Upper-intermediate or higher, sufficient for daily team communication and code review discussions. Bonus: exposure to Linux / command line, Docker basics, message queues (Kafka, RabbitMQ), cloud platforms (AWS, GCP), open-source contributions, hackathon participation, or an active public GitHub portfolio.

🏢 Summary: The offer is for a Python Backend Engineer to build and maintain scalable backend services and REST APIs in a collaborative product environment. The role focuses on developing clean, well-tested code and contributing to architecture and code quality from day one. It is a fully remote position with flexible contract options and long-term international projects. 🗂️ Requirements: 3+ years of professional Python experience, Strong knowledge of FastAPI, Django, or Flask, Experience with PostgreSQL, Experience with REST API design, Proficiency with Git, Experience with pytest, Experience with CI/CD workflows 📃 Skills: Python, FastAPI, Django, Flask, PostgreSQL, REST, Git, pytest, CI/CD, AWS, GCP, Azure, Docker, Kubernetes, Kafka, Redis, RabbitMQ, Poetry, uv 🏢 Description: About the role We're looking for a Python backend engineer to join a client team and build reliable, scalable services from day one. Responsibilities Design and maintain Python-based backend services and REST APIs Write clean, tested, well-documented code Collaborate with product and DevOps teams on feature delivery Participate in code reviews and architecture discussions Requirements 3+ years of professional Python experience Solid knowledge of FastAPI, Django, or Flask Experience with PostgreSQL and RESTful API design Comfortable with Git, pytest, and CI/CD workflows Good written and spoken English Nice to have AWS, GCP, or Azure Docker / Kubernetes Kafka, Redis, or RabbitMQ Poetry or uv for dependency management pre-commit hooks and code quality tooling We offer B2B contract or employment contract (umowa o pracę / umowa zlecenie) — flexible on the form Fully remote, flexible setup Long-term engagements with international clients Dedicated recruiter support through onboarding

🏢 Summary: Backend Engineer role focused on building production systems for AI agents, including backend services, APIs, and data pipelines for enterprise customers. The position involves designing reliable distributed systems, maintaining production services, and collaborating closely with cross-functional teams in a fully on-site Warsaw office environment. The company offers a modern AI-focused tech stack, B2B contract, stock options, and opportunities to contribute to open-source projects. 🗂️ Requirements: 3–5 years of experience building backend production systems, Strong Python skills, Understanding of distributed systems, Experience with AWS, GCP, or Azure, Knowledge of SQL and NoSQL databases, Database design experience, Security-focused approach to system design, Ability to manage projects from idea to production, Strong written and spoken communication skills, Experience using AI tools in software development, Ability to work fully on-site in Warsaw 📃 Skills: Python, AWS, GCP, Azure, SQL, NoSQL, AI, TypeScript, APIs, GitHub, Copilot, Codex, Claude 🏢 Description: Please note: This role requires working from our office in Warsaw city centre 5 days a week . This is a fully on-site position , and remote or hybrid work is not available . About us We believe that businesses are moving toward AI-powered work, and we are building a platform for this future. Many AI agents cannot handle complex business tasks. We created a platform that organizes company policies, workflows, and business knowledge into one AI data model. This helps AI agents make accurate decisions and deliver reliable results at scale. We already work with well-known enterprise customers such as Glovo, Nespresso, and HelloFresh. Our platform supports thousands of users and handles real production data. Customers trust us with important business knowledge because we provide a secure and reliable solution with SOC2, HIPAA-ready security practices, and strong integrations. Job description We are looking for a backend engineer with several years of experience who wants to take responsibility for real systems, not only complete assigned tasks. You will solve backend challenges, choose the best technical solutions, deliver new features, and support them in production. We are looking for someone with good technical skills, clear communication, and a desire to build systems that are simple, reliable, and easy to improve. You will help build production systems for AI agents, working on real problems for customers who already use our platform. The position is based in Warsaw and requires working from the office. Responsibilities Build backend services, APIs, data pipelines, and background processes for production systems. Turn business requirements into technical solutions and implementation plans. Monitor and maintain services after release, improving reliability, performance, and system monitoring. Design service interfaces and data models that fit well into the overall system. Create technical documentation and diagrams when they help the team. Work closely with product managers, frontend engineers, and platform engineers. Improve engineering processes using AI tools, automation, and better workflows. Help maintain high code quality through code reviews and design reviews. Requirements Around 3–5 years of experience building backend production systems. Strong Python skills and the ability to write clean and maintainable code. Good understanding of distributed systems, including concurrency, failures, data consistency, asynchronous processing, and service communication. Experience with cloud platforms such as AWS, GCP, or Azure, and knowledge of SQL, NoSQL, and database design. A security-focused approach when working with sensitive data and system design. Ability to manage projects from idea to production with increasing responsibility. Good written and spoken communication skills, with the ability to explain technical decisions clearly. Experience using AI tools as part of your daily software development work. Nice to have Experience with AI agents, orchestration, retrieval systems, tool calling, or LLM-based infrastructure. Knowledge of TypeScript or willingness to work across the full technology stack. Experience taking on more responsibility and learning quickly. What we offer B2B contract and company stock options. MacBook Pro. Modern technology stack and the opportunity to contribute to open-source projects. An AI-focused development environment with tools such as Claude Code, OpenAI Codex, and GitHub Copilot. Our values Our leadership team combines strong experience in AI, knowledge management, and enterprise SaaS. We have received more than $60 million in funding and have been recognized by Gartner as a Cool Vendor. Our work is guided by these values: Quality – We care about excellent work and high standards in everything we build. Momentum – We take initiative, share ideas, and keep moving forward. Accountability – We take responsibility for our work and give honest, respectful feedback. Hard work – We believe success comes from teamwork, dedication, and consistent effort. Learning agility – We stay curious, learn from mistakes, and continue improving. Adapt and thrive – We welcome change and see challenges as opportunities to grow. Win together – We work as one team, communicate openly, and support our shared goals.

🏢 Summary: Full Stack Developer role responsible for end-to-end architecture and development of a global application automating data collection, compliance reporting, and asset optimization. The position covers frontend (Angular) and backend (Python/FastAPI) development, AI integration, data engineering, and Kubernetes-based DevOps. It involves owning the full product lifecycle in an international, greenfield environment. 🗂️ Requirements: 5+ years of professional software development experience, Expertise in Python and FastAPI, Advanced Angular with TypeScript and RxJS, Strong experience with RESTful microservices, Proficiency in PostgreSQL design and optimization, Hands-on experience with ETL/ELT processes, Experience with Kubernetes and Docker, Experience with CI/CD pipelines (Jenkins or BitBucket), Experience working in SCRUM or Kanban, Bachelor’s degree in Computer Science or related field, Fluent English (B2/C1) 📃 Skills: Python, FastAPI, Angular, TypeScript, RxJS, REST, PostgreSQL, ETL, ELT, Kubernetes, Docker, Jenkins, BitBucket, S3, Linux, SCRUM, Kanban, LLM, AI 🏢 Description: Role Summary We are seeking an experienced Full Stack Developer to join an IT Hub in Poland. You will own the full product lifecycle of a global application designed to automate data collection, compliance reporting, and asset optimization across EMEA, APAC, and Americas. Key Responsibilities Architecture & Development: Design end-to-end modular architecture and develop both Frontend (Angular) and Backend (Python/FastAPI) components. Innovation: Integrate AI tools (LLMs, Code Assistants) to enhance development and automate complex data workflows. DevOps: Manage deployment and scalability on Kubernetes clusters using CI/CD pipelines. Data Management: Handle complex data consolidation, ETL processes, and PostgreSQL optimization. Technical Requirements Backend: Expert Python (FastAPI, RESTful microservices, automation scripts). Frontend: Advanced Angular (TypeScript, RxJS, complex forms/UI). Data: Mastery of PostgreSQL (design & optimization) and ETL/ELT processes. Infrastructure: Kubernetes, Docker, CI/CD (Jenkins/BitBucket), S3 Buckets, and Linux. Methodology: Strong experience in SCRUM/Kanban environments. Qualifications Experience: 5+ years of professional software development. Education: Bachelor’s degree in Computer Science or a related field. Languages: Fluent English (B2/C1) . Soft Skills: Analytical mindset, ability to work autonomously, and strong negotiation skills. What We Offer Opportunity to work on a greenfield project within a prestigious global financial group. Exposure to cutting-edge technologies and international stakeholders. A multicultural, professional environment focused on innovation and agility.

🏢 Summary: Backend Python Developer role owning end-to-end product development across backend systems, from architecture and implementation to deployment. The position focuses on building scalable applications, designing RESTful APIs, and working with cloud and data technologies. You will drive backend architecture decisions and deliver high-quality features in a production environment. 🗂️ Requirements: 8+ years of professional software engineering experience, Strong production experience with Python, Experience building scalable, high-quality applications, Deep understanding of backend architecture, Strong knowledge of RESTful API design, Strong experience with PostgreSQL, Hands-on experience with AWS, Experience with Elasticsearch, Experience working in Agile environments, Experience with Test-Driven Development (TDD) 📃 Skills: Python, PostgreSQL, AWS, Elasticsearch, REST, TDD, Agile, GCP, Snowflake, TypeScript, PHP, JavaScript 🏢 Description: Role Overview We’re looking for a Backend Python Developer to take ownership of product development across backend systems. You’ll work across the full development lifecycle — from architecture and implementation through to deployment — partnering closely with Product and Engineering. Must Have (Non-Negotiable) Strong hands-on experience with Python in production environments 8+ years of experience building scalable, high-quality software applications Deep understanding of backend architecture and RESTful API design Strong experience with relational databases (PostgreSQL preferred) Hands-on experience with AWS Proven ability to design, build, and ship end-to-end features independently Nice to Have TypeScript PHP Basic familiarity with JavaScript Elasticsearch Snowflake or modern data warehousing platforms Familiarity with GCP Key Responsibilities Product Development: Lead the development efforts, taking ownership of the entire product lifecycle from ideation to implementation. Collaborate with cross-functional teams, including product managers and engineers, to deliver high-quality products. Technical Leadership: Apply expertise in technologies to drive the adoption of new architectures and design patterns for our products. Mentor and guide junior developers, fostering a culture of continuous learning and improvement within the team. Innovation and Best Practices: Actively contribute to the evolution of our technical stack, ensuring it aligns with industry standards and supports scalability and maintainability. Cross-Functional Collaboration: Work closely with cross-functional teams to ensure backend systems effectively support product requirements. Your Professional Qualifications 🌟 Core Experience & Technical Skills Extensive Experience: 8+ years of professional experience as a Software Engineer delivering high-quality, scalable applications. Mandatory Backend Expertise: Proven, in-depth experience with Python Database Proficiency: Strong experience with relational databases, specifically PostgreSQL (Postgres). Search & Indexing: Direct experience designing, implementing, and optimizing solutions using Elasticsearch. Cloud Computing: Hands-on experience with AWS (mandatory), with familiarity with GCP as a bonus. Data Warehouse (Nice to Have): Experience working with modern data warehousing solutions like Snowflake. 🏗️ Architecture & Design Component Design: Experience with a shared component design paradigm utilizing controller-based patterns. Application Implementation: Proven track record of implementing applications effectively using established style guides and detailed wireframes. Backend Principles: Strong understanding of backend architecture principles and best practices for RESTful design. 📈 Development Methodologies & Teamwork Agile Development: Comfortable working in Agile environments and proficient in Test-Driven Development (TDD) methodologies. Collaboration: Highly team-oriented and collaborative, with the proven capacity to mentor junior team members and elevate team skill levels. Leadership & Communication: Demonstrated leadership ability combined with excellent written and verbal English skills. About Mozaiq Mozaiq is a fully remote team with roots in the US and Eastern Europe. We build powerful, cross-functional teams that support some of the most sophisticated tech and marketing organizations in the world. 🌐 Global Family: A tight-knit, multicultural, remote-first team 💼 Meaningful Work: Support world-class brands and products 🤝 Inclusive Culture: We prioritize collaboration, clarity, and growth Perks & Benefits 🌍 Work from anywhere ⏳ Flexible hours 🏝 Paid time off + holidays 🛫 Team offsites 🩺 Subsidised Health insurance

🏢 Summary: The role involves full ownership of software products, covering architecture design, development, deployment, and maintenance within distributed systems. It focuses on building RESTful microservices, automation tools, and modular components to industrialize asset management processes. The position also ensures system integration, cloud-native deployment, and ongoing optimization in a DevOps environment. 🗂️ Requirements: Advanced proficiency in Python, Experience building RESTful microservices, Experience with ETL data processing, Basic knowledge of Java, Foundational understanding of Spring Boot, Proficiency in PostgreSQL design and optimization, Familiarity with S3 or NAS storage, Experience with Kubernetes and Docker, Experience with CI/CD pipelines, Working knowledge of Linux environments 📃 Skills: Python, Java, Spring, PostgreSQL, S3, NAS, Kubernetes, Docker, Jenkins, BitBucket, Linux, ETL, REST 🏢 Description: Key Responsibilities: End-to-End Product Ownership: Manages the full software lifecycle, from initial concept and architecture design to production release and maintenance. Workflow Automation: Develops internal tools to automate data collection, remediation, and reporting to industrialize asset management processes. Modular Development: Delivers independent, high-quality software modules through iterative cycles of coding, testing, and documentation. System Integration: Ensures seamless integration and maintenance of applications within complex, distributed infrastructures. Technical Collaboration: Works closely with architects and product owners to define technical solutions and security standards. Technical Requirements: Python Expertise: Advanced proficiency in Python for building RESTful microservices, automation scripts, and ETL data processing. Basic Java Knowledge: Foundational understanding of Java and Spring Boot to support existing backend components and minor maintenance tasks. Data & Storage: Proficiency in PostgreSQL (design and optimization) and familiarity with S3 or NAS storage solutions. Cloud & DevOps: Familiarity with Kubernetes, Docker, and CI/CD pipelines (Jenkins, BitBucket) within a Linux environment.

🏢 Summary: The offer is for a Test Automation Engineer with strong Python and React experience, responsible for developing manual and automated tests and maintaining automation pipelines. The role involves backend development in Python (Web), defining BDD scenarios, and ensuring software quality through robust testing practices. 🗂️ Requirements: Minimum 3 years of experience with Python (Web) development, Minimum 3 years of experience with React, Experience with Git version control, Experience with FastAPI, Experience with PostgreSQL, Experience with BDD using Cucumber and Behave, Experience in test automation, Knowledge of basic software design principles 📃 Skills: Python, React, Git, FastAPI, PostgreSQL, Cucumber, Behave, BDD, Testing, Automation, Design 🏢 Description: Responsibilities: Creating and developing both manual and automated tests Building and maintaining test automation pipelines Working on backend components in Python (Web) Collaborating with the team to define BDD scenarios (Cucumber / Behave) Maintaining technical documentation and ensuring solution quality Requirements: Experience with Python (Web) development (minimum 3+ years) 3 years of experience with React Experience with Git for version control, FastAPI and PostgreSQL Experience with BDD testing using Cucumber and Behave, including an analytical approach to defining test scenarios Experience with test automation and basic software design principles Ability to work independently, proactively, and autonomously without ongoing supervision Ability to clearly communicate needs and take responsibility for delivering assigned tasks Very good command of English, both spoken and written Nice to have: Experience with MS UI Automation API Knowledge of Qt 6 Offer: Private medical care Co-financing for the sports card Constant support of dedicated consultant Employee referral program

🏢 Summary: Senior Backend Engineer role focused on designing, building, deploying, and maintaining scalable backend systems using TypeScript and Node.js in a cloud environment. The position involves developing microservices on AWS, shaping system architecture across platforms, and ensuring production reliability for international users. Strong emphasis on clean architecture, testing, and infrastructure as code. 🗂️ Requirements: 5+ years backend development experience in production environments, Expert hands-on experience with TypeScript and Node.js, Strong knowledge of software engineering principles, testing, data structures, and algorithms, Experience designing and developing REST APIs, Experience with event-driven architecture, Experience building and maintaining microservices, Hands-on experience with AWS cloud services, Experience with Infrastructure as Code using Terraform, Experience with CI/CD pipelines and related tools, Strong knowledge of PostgreSQL and DynamoDB, Proficiency in OO design patterns, SOLID principles, and Clean Code, Computer Science degree, Experience working with Agile methodologies such as SCRUM or Kanban 📃 Skills: TypeScript, JavaScript, Node.js, AWS, Terraform, CircleCI, Docker, Datadog, PostgreSQL, DynamoDB, REST, CICD, Microservices, OOP, SOLID, Algorithms, DataStructures, SCRUM, Kanban 🏢 Description: About the role You will need to be an expert in backend development with a thorough understanding of the technologies involved. Strong backend skills where you can demonstrate your ability to apply these technologies, as well as deploy and maintain them will be crucial to success. Technologies we work with: Typescript, JavaScript, Node.js, REST APIs, AWS, Terraform Responsibilities: Designing, writing, testing functionalities for a backend system written in TypeScript, Node.js Deploying and maintaining microservices in AWS using Terraform Design software architecture between backend, frontend and mobile apps Maintaining system on production used by consumers from several European countries Debugging issues Scoping and assessing the complexity of features Participating in sprint planning, daily sprints and meetings with product owners for grooming new features Recruiting and mentoring team members Collaborating with other team members and teams that depend on the functionalities that you develop Required qualifications: 5+ years of production software development experience in backend Strong understanding of software engineering principles, testing, data structures and algorithms Expert hands-on experience in technologies such as Typescript / Node.js Experience in developing Cloud and Infrastructure solutions with AWS and CI/CD processes supported by tools like Terraform, CircleCI, Docker, Datadog, etc. Strong knowledge of DBMS like PostgreSQL, DynamoDB Expertise in REST APIs, Experience in event driven architecture Proficiency in OO design patterns, SOLID principles, Clean Code and solving architectural problems Computer Science degree Experience working with Agile methodologies such as SCRUM and/or Kanban Good communication and collaboration skills Self-motivation, proactive attitude Proficiency in English Nice to have: Exposure to frontend development in React Working experience with one of the object-oriented and/or functional languages such as C#, Python Java, Golang, Kotlin

🏢 Summary: Part-time Backend Developer role for early-career candidates or students, focused on building and maintaining web applications using Python, Django, and microservices architecture. The position involves developing, testing, debugging, and documenting backend solutions, as well as participating in code reviews. It offers hands-on experience in modern backend development within a collaborative team environment. 🗂️ Requirements: Experience with Python, Experience with Django framework, Knowledge of RESTful APIs, Knowledge of microservices architecture, Experience with SQL, Experience with PostgreSQL, Knowledge of data modeling, Knowledge of data warehouse concepts, Knowledge of software testing methodologies, Ability to create unit tests, Understanding of clean code principles, Familiarity with design patterns, Ability to read technical documentation in English, Adherence to software development best practices 📃 Skills: Python, Django, REST, Microservices, SQL, PostgreSQL, APIs, UnitTesting, IntegrationTesting, SystemTesting, DataModeling, DataWarehouse, GitHub, GitLab 🏢 Description: Who we are looking for: We are looking for a Backend Developer, available for at least half-time, to join our team. If you are at the beginning of your professional career or currently studying, this job is for you. Responsibilities: implementing and developing software based on Python, Django, and microservices technologies, designing and developing web applications, running, testing, and debugging implemented software, creating unit tests, documenting the source code you create, conducting code reviews of source code written by other team members. Requirements: experience with Python and the Django framework, knowledge of RESTful APIs, microservices architecture, and best practices in API design, experience with SQL, especially PostgreSQL, data modeling, and data warehouse concepts, English proficiency sufficient to read technical documentation, creative, solution-oriented problem-solving skills, knowledge of software testing methodologies, including unit, integration, and system testing, openness toward others and the ability to work in a team, willingness to learn new technologies, adherence to software development best practices, knowledge and application of clean code principles, and familiarity with design patterns. Nice to have: knowledge of industry trends, emerging technologies, and best practices in software development, personal projects in your portfolio, familiarity with code repository management platforms such as GitHub or GitLab, documented ability to lead and comprehensively manage complex projects, from initial planning and scope definition through successful implementation and delivery, ensuring timely execution and alignment with business goals. We offer: sports card co-funding, company events, opportunities to learn and gain experience, prospects of working on interesting and diverse projects, participation in industry events, the possibility to work 100% remotely.

🏢 Summary: Senior Backend Engineer role focused on designing, building, and maintaining production backend systems and AI-driven workflows in a fully onsite Warsaw office environment. The position involves ownership of system architecture, APIs, distributed systems, and cloud infrastructure from design through production. Candidates will collaborate across teams, improve engineering processes with AI tools, and contribute to scalable, reliable solutions. 🗂️ Requirements: Strong experience as a senior backend engineer on production systems, Excellent Python programming skills, Understanding of distributed systems, Experience with AWS or Azure cloud platforms, Knowledge of SQL and NoSQL databases, Experience with asynchronous processing and service design, Ability to design and deliver systems from idea to production, Strong written and spoken communication skills, Regular use of AI development tools, Ability to work fully onsite in Warsaw 📃 Skills: Python, AWS, Azure, SQL, NoSQL, APIs, AI, TypeScript, GitHub, Copilot, Claude, OpenAI, Codex 🏢 Description: Please note: This role requires working from our office in Warsaw city centre 5 days a week . This is a fully on-site position , and remote or hybrid work is not available . About Us Many companies want to use AI agents, but these agents often struggle with real business tasks. We solve this problem by building a platform that helps AI understand business rules, workflows, and processes. This allows AI to make better decisions and provide accurate, reliable, and compliant results. Well-known companies from different industries use our technology to automate up to 85% of customer cases, reduce handling time by 20–25%, and complete tasks that used to take hours in just seconds. We also work with leading technology partners and have been recognized for our innovative approach. Our goal is to help people everywhere get better answers through AI. Job Description We are looking for a Senior Backend Engineer who can take ownership of important systems instead of only completing assigned tasks. You will solve complex problems, design backend solutions, build them, and make sure they run well in production. We want someone with strong technical skills, good communication, and the ability to create simple, reliable, and easy-to-maintain systems. This is a product engineering role with responsibility from system design to production. The position is based in Warsaw and requires office work. Responsibilities Design and develop backend services, APIs, data processing, and background tasks for production systems. Turn unclear business needs into clear technical plans and practical solutions. Maintain services after release by improving reliability, monitoring, performance, and fixing issues. Make good decisions about system architecture, data models, interfaces, and future scaling. Write technical documentation, architecture notes, and diagrams when they help the team. Work closely with product managers, frontend engineers, and platform engineers to deliver complete solutions. Improve development processes using AI tools, automation, and internal workflows. Support the team through code reviews, design reviews, and practical technical leadership. Requirements Strong experience as a senior backend engineer working on production systems. Excellent Python skills and the ability to write clean and maintainable code. Good understanding of distributed systems, including concurrency, failure handling, data consistency, asynchronous processing, and service design. Experience with cloud platforms such as AWS, Azure, or similar services. Knowledge of SQL, NoSQL databases, schema design, and performance optimization. Ability to take a project from an idea through design and implementation to production. Strong written and spoken communication skills with the ability to explain technical topics clearly. Regular use of AI tools in everyday development and interest in improving AI-based workflows. Nice to Have Experience with LLM-based applications, search systems, AI infrastructure, or large data pipelines. Knowledge of TypeScript or the ability to contribute to frontend development when needed. Experience guiding other engineers and influencing technical decisions without being a formal manager. What We Offer B2B contract and company stock options. MacBook Pro for work. Modern technology stack and opportunities to contribute to open-source projects. Access to advanced AI development tools, including GitHub Copilot, Claude Code, OpenAI Codex, TypingMind, and MCP servers. Our Culture and Values Our leadership team has strong experience in AI and knowledge management. We have secured more than $60 million in funding and achieved three years of continuous 3x growth. Our work is based on these values: Quality – We aim for excellent work and high coding standards. Momentum – We take initiative and keep projects moving forward. Accountability – We take responsibility and give honest, respectful feedback. Hard Work – We believe great results come from teamwork and consistent effort. Learning Agility – We stay curious, learn from mistakes, and improve every day. Adapt and Thrive – We accept change and see challenges as opportunities. Win Together – We succeed as one team through honesty, openness, and support for our shared mission.