Senior Software Engineer

🏢 Summary: Full-stack Software Engineer role focused on designing, building, and maintaining scalable web applications, APIs, and backend services in an AI-first engineering environment. The position emphasizes ownership of AI-assisted development, rigorous code review, test coverage, and reliable CI/CD practices. Engineers collaborate cross-functionally and are accountable for production outcomes across the product lifecycle. 🗂️ Requirements: 2–4+ years experience building web applications, backend services, or APIs, Hands-on experience using AI agents in software development workflows, Ability to review and validate AI-generated code, Experience working in agile and CI/CD environments, Commitment to writing well-tested, reliable software, Strong ownership of production outcomes 📃 Skills: PHP, Laravel, Vue.js, MySQL, DynamoDB, Kubernetes, AWS, Serverless, APIs, CI/CD 🏢 Description: About the Role: Loop is looking for a full-stack Software Engineer to contribute directly to the design, development, and maintenance of core products. You'll build scalable solutions, uphold technical excellence, and be a reliable partner to the engineers around you. AI at Loop Engineering Engineering is AI-first; not aspirationally, but operationally. Every engineer is provisioned with Claude Code and Cursor, and AI agents are the default starting point before opening a file. The role has shifted: you are not primarily a writer of code. You are the judgment layer, determining what should be built, validating that what was built is correct, and owning the outcome in production. AI handles a growing share of implementation, and you own everything that surrounds it. Our Tech Stack: PHP/Laravel, Vue.js, MySQL, DynamoDB, Kubernetes, AWS, Serverless. The hiring process is tech-stack agnostic. What You'll Do - Design, build, and maintain web applications, APIs, backend services, and lambdas for the product line - Start with the agent, not the editor; invest time in planning and intent articulation - Review AI-generated code with rigor and ensure correctness - Include meaningful test coverage in every PR and contribute to a healthy CI/CD process - Collaborate closely with engineers, product managers, and designers - Exhibit ownership: ensure features are stable in production, flag risks early, and make reversible decisions fast - Improve system effectiveness beyond immediate scope, including code review quality and cross-team visibility Your Experience - 2–4+ years building web applications, backend services, or APIs - Use AI agents as a default starting point and articulate your workflow for planning, prompting, and reviewing - Experience identifying and correcting issues in AI-generated code - Clear perspective on where AI adds value and where it introduces risk - Experience with PHP/Laravel, AWS Serverless, or Vue.js is a strong plus - Experience working in agile, CI/CD environments - Commitment to building well-tested, reliable software - Ability to learn from mistakes, seek feedback, and grow through iteration

🏢 Summary: Forward Deployed Engineer role focused on embedding with enterprise customers to design, build, and ship integrated solutions on top of an AI-driven logistics data platform. You will lead technical discovery, integrate complex legacy systems (ERP, TMS, EDI, payments), and deliver production-ready solutions that drive measurable client results. The position combines hands-on engineering, customer-facing ownership, and early-stage function building in a high-growth environment. 🗂️ Requirements: 3-5 years of software engineering experience, Hands-on integration experience with enterprise systems (ERP, TMS, EDI, payment systems or similar), Strong production-level coding ability, Experience shipping end-to-end solutions in early-stage or high-growth environments, Ability to work in ambiguous, customer-facing environments with minimal oversight, Strong ability to translate technical constraints into business language 📃 Skills: APIs, EDI, ERP, TMS, Payments, Integration, Data, LegacySystems 🏢 Description: About You Loop is bringing AI to an industry that still runs on PDFs, phone calls, and tribal knowledge. You are 75% engineer, 25% product-founder mind. You write production code and navigate legacy systems with equal confidence, and translate customer needs into buildable requirements. You have real integration experience with enterprise customer systems. As a Forward Deployed Engineer, you will operate embedded with customers, learning their operations and building working solutions that drive client results and feed product direction. You own the problem end-to-end, from commercial discovery through technical delivery. This is an engineering role with autonomy to shape how an early-stage function operates. This role is on-site 4+ days per week through a combination of customer visits and in-person collaboration. What You'll Do - Qualify opportunities and lead technical discovery: map customer systems, assess technical fit, and produce scoped project plans. - Embed with customers to build and ship working solutions, iterate on feedback, and deliver a working v1 using platform primitives or custom builds. - Integrate customer systems with the platform including APIs, EDI feeds, ERPs, TMS platforms, and payment systems, handling complex underlying data. - Own customer relationships and deployment timelines, run meetings and demos, and travel to customer sites as needed. - Debrief deployments to identify repeatable patterns and productization opportunities. - Help refine processes and contribute to the team playbook. Qualifications - 3-5 years of software engineering experience. - Hands-on integration experience with enterprise customer systems such as ERPs, TMS platforms, EDI feeds, payment systems, or comparable legacy environments. - Strong coding skills meeting a high engineering bar and comfort navigating legacy systems. - Experience at early-stage or high-growth companies delivering end-to-end solutions. - Comfortable in ambiguous, customer-facing environments. - Strong communication skills across technical and business stakeholders. Nice to Have - Experience owning full-cycle customer deployments from discovery to shipping v1. - Background as Forward Deployed Engineer, implementation engineer, technical founder, field engineer, or applied AI engineer deploying into enterprise workflows. - Domain experience in supply chain, logistics, freight, or transportation. - Founder experience or leading technical initiatives from zero. Compensation and Benefits - Base salary range: $150,000 to $260,000 annually. - Eligibility for equity. - Health, dental, and vision insurance. - 401(k) match. - Paid time off and paid holidays. - Parental leave.

🏢 Summary: Full-stack engineering role focused on building and shipping production AI-powered features that automate logistics billing and payments. The position involves working across frontend, backend, and infrastructure to deliver scalable, high-quality solutions in a fast-paced early-stage environment. Engineers collaborate cross-functionally and leverage modern AI tools to accelerate development and impact core product decisions. 🗂️ Requirements: Minimum 2 years of software engineering experience, Experience with TypeScript, Experience with React, Experience with Node.js, Experience with GraphQL, Experience shipping products end-to-end in early-stage environments, Ability to work across frontend, backend, and infrastructure layers, Willingness to work onsite in SF or Chicago three days per week 📃 Skills: TypeScript, React, Node.js, GraphQL, Relay, Prisma, NestJS, PostgreSQL, Kafka, Redis, Elasticsearch, AWS, CDK, Fargate, ECS, Vite, AntDesign 🏢 Description: About Loop Loop is the data platform for the global supply chain. Logistics runs on messy, unstructured data—trapped in PDFs, emails, and legacy systems. We use AI to structure this chaos, creating a "source of truth" that automates payments and audits for the Fortune 100. We are building the financial nervous system for a $100 trillion physical economy. Our technology ensures freight moves efficiently and carriers get paid instantly. Backed by Founders Fund, Index Ventures and 8VC, we are scaling rapidly. We are looking for engineers ready to deploy production AI that powers the physical economy. About YouAs a full-stack engineer, you will work closely with founders and customers to understand and solve their logistics billing and payment pain points. You will help define the product and ship features that directly impact our customers. You will face and solve many complex technical challenges while you receive guidance and feedback from the team. You will shape the Loop DNA and define how we grow as a company. Responsibilities Work cross-functionally with product, design, and sales to understand requirements and ship thoughtful solutions. Write high-quality code optimized for extensibility. Engage in code reviews to maintain a high bar of engineering excellence. Lead discussions and documentation to communicate and arrive at the best technical design. Work across different component boundaries, from frontend to backend, and even infrastructure layers. Adopt AI technologies such as Cursor/Codex/Claude to accelerate software development and champion adoption of AI tools across the organization for increased productivity. Promote better practices and share technical knowledge across the team. Help grow Loop through deliberate feedback on product, process, and culture. Qualifications Willing to work in the SF or Chicago office three days a week Two years of software engineering experience. Experience with TypeScript and tools such as GraphQL, Relay, React, and Node.js. Experience working at early-stage companies where you shipped products end-to-end and wore many hats. Under the Hood Infrastructure: AWS, CDK, Fargate ECS Backend: TypeScript, Node.js, Prisma, NestJS, PostgreSQL, Kafka, Redis, Elasticsearch, GraphQL Frontend: TypeScript, React, Relay, Ant Design, Vite, GraphQL Compensation Base pay 150k+ per year Benefits & Perks Premium Medical, Dental, and Vision Insurance plans Insurance premiums covered 100% for you Unlimited PTO Fireside chats with industry leading keynote speakers Generous professional development budget to feed your curiosity Physical and Mental fitness subsidies for yoga, meditation, gym, or ski memberships Why you should join Loop? #LI-LOOP

🏢 Summary: Opportunity to join an AI Ops team building and scaling AI-powered automation systems for global supply chain operations, partnering closely with engineering, product, and customers to drive adoption and deliver measurable value. The role focuses on deploying intelligent workflows, translating complex technical systems for users, and embedding with customer and operations teams to enhance execution. This is an onsite position in Chicago, San Francisco, or New York City. 🗂️ Requirements: College degree in analytics, finance, economics, STEM or related quantitative field, 1+ year experience in technology, data analysis or other technical quantitative field, Ability to understand complex technical systems and translate them for users, Experience working cross-functionally with engineering, product, or operations teams, Onsite availability 4+ days per week in Chicago, San Francisco, or New York City 📃 Skills: SQL, Python, Excel, Automation, Data, AI 🏢 Description: About the Role Loop is building an AI ops team that will own key automation and intelligence systems as Loop builds and scales them across its customer base. The team is disrupting traditional operations with AI-powered workflows that create 100X leverage for users, turning operators into analysts. Responsibilities include close partnership with engineering and product teams, internal roll-out of new systems and products, and driving adoption across the user base. This role requires a deep understanding of systems and their users (internal and external), the ability to translate complex technical work to everyday users, and strong problem-solving skills. This is an in-person role based in Chicago, San Francisco, or New York City, with the expectation of being onsite 4+ days per week. What You'll Do - Accelerate delivery of new product capabilities for global brands by understanding how customer outcomes are driven - Embed with customer, product, and operations teams to deliver increased customer value - Partner with AI engineers to deploy systems and products that automate workflows, reduce manual work, and improve user experience - Demonstrate strong execution skills and deep knowledge of the product offering and customer pain points - Build and maintain relationships with internal customer-facing stakeholders to ensure value delivery About You - College degree with a quantitative background in analytics, finance, economics, or similar STEM field - 1+ years of work experience in technology, data analysis, or other technical and quantitative fields - Ability to balance eagerness to learn with strong execution and problem-solving skills - Team-oriented mindset with interest in fast-paced, high-growth environments - Advanced Excel skills and SQL, Python, or other programming experience are a plus Compensation and Benefits The base pay range for this role is $80,000 to $125,000 annually, depending on experience, skills, qualifications, location, and business needs. In addition to base salary, the role may be eligible for equity. Benefits include health, dental, and vision insurance, 401(k) match, paid time off, paid holidays, and parental leave. Equal Opportunity The company is an equal opportunity employer committed to creating an inclusive environment for all employees. All qualified applicants will receive consideration without regard to legally protected characteristics.

🏢 Summary: Senior Full Stack Engineer role focused on building and owning end-to-end product features for an AI-driven platform that automates complex business processes. The position involves developing frontend and backend solutions, designing APIs, improving performance and usability, and leveraging AI tools in daily engineering work. The role is office-based in Warsaw and requires strong product thinking and production-level experience. 🗂️ Requirements: Senior-level experience building production web applications, Strong knowledge of React and TypeScript or similar frontend framework, Experience designing and developing backend APIs and application logic, Ability to build and maintain frontend and backend features end-to-end, Experience working with production environments and monitoring released features, Daily use of AI tools for development and problem-solving, Strong understanding of code quality, testing, and long-term ownership 📃 Skills: React, TypeScript, JavaScript, API, REST, Node.js, Python, GitHub, Copilot, Claude, OpenAI, Codex, TypingMind, MCP, AI 🏢 Description: About Us Many companies want to use AI agents, but these agents often have problems with complex business tasks. We help solve this issue. Our platform understands company rules, processes, and workflows, so AI can make better decisions instead of only giving simple answers. This allows businesses to use AI that is accurate, follows company policies, and can be trusted. Well-known companies 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 a few seconds. We work with leading technology partners and have received industry recognition for our innovative approach. Our mission is to give people better answers everywhere. About the Role We are looking for a Senior Full Stack Engineer with strong product thinking. In this role, you will own features from start to finish. You will understand user needs, plan solutions, build frontend and backend functionality, release new features, and improve them based on user feedback. You should feel comfortable working on user interfaces, APIs, and production quality while collaborating with product and design teams. Location: Warsaw (office-based). Responsibilities Build and deliver product features across both frontend and backend. Turn product ideas into practical and effective solutions. Work with user interfaces, business logic, APIs, and data flows. Cooperate closely with product managers and designers, even when requirements are still developing. Improve usability, performance, reliability, and overall user experience. Monitor released features and use production data to make improvements. Use AI tools every day to work faster and improve engineering processes. Maintain high standards for code quality, testing, and long-term ownership. Requirements Strong experience as a senior engineer building production web applications. Good knowledge of React, TypeScript, or a similar modern frontend framework. Experience designing and developing backend APIs and application logic. Strong product mindset with the ability to identify and improve weak user experiences. Good decision-making skills when balancing scope, speed, and technical quality. Clear communication and teamwork across engineering, product, and design. Daily experience using AI tools for development and problem-solving. Nice to Have Experience building AI-powered products such as chat, search, recommendation systems, workflows, or AI agents. Knowledge of Python, Node.js, or both. Experience owning product areas independently. Understanding of performance optimization, accessibility, and high-quality web applications. What We Offer B2B contract and company stock options. MacBook Pro for work. Modern technology stack with opportunities to contribute to open-source projects. Advanced AI development tools, including GitHub Copilot, Claude Code, OpenAI Codex, TypingMind, and MCP Servers. Why Join Us Our leadership team has strong experience in knowledge management and AI. We have raised more than $60 million in funding and achieved three years of continuous 3x growth. Our work is guided by these core values: Quality: We aim for excellent craftsmanship and high standards in everything we build. Momentum: We take initiative and keep projects moving forward. Accountability: We take responsibility, give honest feedback, and support each other. Hard Work: We believe difficult goals require dedication and teamwork. Learning Agility: We stay curious, learn from mistakes, and keep improving. Adapt and Thrive: We accept change and see challenges as opportunities. Win Together: We succeed as a team through honesty, openness, and shared commitment.

🏢 Summary: Senior Fullstack Engineer role focused on designing and scaling production-grade web systems, owning the full product experience from backend to frontend. The position combines product thinking with engineering, emphasizing AI-augmented features and modern fullstack architecture. You will work on complex, mission-critical applications with strong autonomy and technical ownership. 🗂️ Requirements: 5+ years of experience building complex web applications, Strong proficiency in Python or Ruby, Strong proficiency in Vue.js or React.js, Solid understanding of SQL and PostgreSQL, Experience with CI/CD pipelines, Experience with cloud environments, Experience using AI/LLM tools in development workflows, Fluent English (C1) 📃 Skills: Python, Ruby, Vue.js, React.js, PostgreSQL, SQL, AWS, Docker, CI/CD, Claude, Cursor 🏢 Description: At Upside , we’re partnering with ambitious companies across the globe to solve complex, meaningful problems through technology. We work in focused teams, combining engineering, product thinking, and design, to deliver outcomes, not just output. Open-source is a strategic part of our work. We build and maintain a number of open-source projects that support our clients and internal R&D. Our latest release is Enthusiast , a customizable agentic AI toolkit for e-commerce. What it means for you You’ll have a "Founder" mindset. You won’t just build a UI or a database - you’ll own the entire product experience. You’ll be a technical partner to stakeholders, helping them understand what’s possible with modern tech and AI. You’ll have the autonomy to experiment across the stack and the responsibility to deliver tools that actually solve business problems. You’ll work at the intersection of product thinking and engineering, deploying AI-augmented features across the entire stack. Role Overview As a Senior Fullstack Engineer, you’ll design and scale resilient systems from the ground up. You’ll bridge the gap between backend logic and frontend experience, ensuring a seamless, production-grade product. Responsibilities End-to-End Ownership: Lead the design and implementation of both backend systems and frontend interfaces. Proactive Solutions: Don't just flag blockers—come with proposals and experiments to bypass them. Consulting: Translate complex business needs into elegant, scalable fullstack architecture. Engineering Standards: Advocate for code quality, security, and performance across the entire repo. Continuous Improvement: Constantly evaluate new tech (especially AI/LLM) to improve delivery. Requirements Experience: 5+ years of building complex web applications. Backend: Strong proficiency in Python or Ruby. Frontend: Mastery of Vue.js or React.js . Infrastructure: Solid understanding of SQL (PostgreSQL), CI/CD, and cloud environments. AI-Native: You use tools like Claude or Cursor to build better and faster. English: Fluent (C1) for direct client collaboration. Tech Stack: Python, Ruby, Vue.js , React.js , PostgreSQL, AWS, Docker. Value Proposition Built for the long run We hire for the company, not just a project - looking for passion driven engineers who want to grow with Upside over time Small teams, real accountability. 3-9 people per engagement. We're small by design. That means your decisions carry weight and you are visible. Mission-critical work: We handle complex  projects that move the needle for international brands. Our clients are scaling companies, established international brands, and large institutions. The systems you build will be under real load, with real stakes. Real Ownership: You take part in the decision making process on technology and implementation..You’re empowered to take initiative, experiment, and drive solutions that create real impact. No Micromanagement: We trust you to own your work and deliver outcomes - no unnecessary oversight. Collaborative R&D: Contribute to targeted Open-source projects and internal AI research. Growth through challenges: Complex problems and direct client exposure means you’ll grow by action. Applied AI as a first-class discipline. We don't bolt AI onto projects as an afterthought. You'll identify where it genuinely moves the needle and lead the implementation - on client work and on our own open-source tooling. The tools you want. If something makes you faster or sharper, we want you using it. Transparent progression path. We have defined engineering levels with clear criteria - you'll know exactly what each role looks like, and what it takes to get from one to the other. No ambiguity, no waiting for someone above you to move on If you didn't find all the information you were looking for, have a look at our handbook - it covers a variety of different matters that could be important at this stage. If there's anything else we did not mention that you're interested in - share your thoughts with us careers@upsidelab.io Compensation & Location Salary: Senior Engineer: 20 800 - 25 900 PLN net + VAT Lead Engineer: >25 900 PLN net + VAT Location: Office in Kraków, hybrid, fully-remote.

🏢 Summary: Senior Fullstack Engineer role focused on designing and scaling production-grade web systems end-to-end, combining backend, frontend, and AI-driven features. The position emphasizes ownership of the full product experience, from architecture to deployment, in client-facing, mission-critical projects. Engineers work across the stack with strong autonomy, applying modern AI tools and best engineering practices. 🗂️ Requirements: 5+ years of experience building complex web applications, Strong proficiency in Python or Ruby, Advanced knowledge of Vue.js or React.js, Solid understanding of SQL and PostgreSQL, Experience with CI/CD pipelines, Experience with cloud environments, Hands-on use of AI tools such as Claude or Cursor, Fluent English (C1 level) 📃 Skills: Python, Ruby, Vue.js, React.js, PostgreSQL, SQL, AWS, Docker, CI/CD, Claude, Cursor 🏢 Description: At Upside , we’re partnering with ambitious companies across the globe to solve complex, meaningful problems through technology. We work in focused teams, combining engineering, product thinking, and design, to deliver outcomes, not just output. Open-source is a strategic part of our work. We build and maintain a number of open-source projects that support our clients and internal R&D. Our latest release is Enthusiast , a customizable agentic AI toolkit for e-commerce. What it means for you You’ll have a "Founder" mindset. You won’t just build a UI or a database - you’ll own the entire product experience. You’ll be a technical partner to stakeholders, helping them understand what’s possible with modern tech and AI. You’ll have the autonomy to experiment across the stack and the responsibility to deliver tools that actually solve business problems. You’ll work at the intersection of product thinking and engineering, deploying AI-augmented features across the entire stack. Role Overview As a Senior Fullstack Engineer, you’ll design and scale resilient systems from the ground up. You’ll bridge the gap between backend logic and frontend experience, ensuring a seamless, production-grade product. Responsibilities End-to-End Ownership: Lead the design and implementation of both backend systems and frontend interfaces. Proactive Solutions: Don't just flag blockers—come with proposals and experiments to bypass them. Consulting: Translate complex business needs into elegant, scalable fullstack architecture. Engineering Standards: Advocate for code quality, security, and performance across the entire repo. Continuous Improvement: Constantly evaluate new tech (especially AI/LLM) to improve delivery. Requirements Experience: 5+ years of building complex web applications. Backend: Strong proficiency in Python or Ruby. Frontend: Mastery of Vue.js or React.js . Infrastructure: Solid understanding of SQL (PostgreSQL), CI/CD, and cloud environments. AI-Native: You use tools like Claude or Cursor to build better and faster. English: Fluent (C1) for direct client collaboration. Tech Stack: Python, Ruby, Vue.js , React.js , PostgreSQL, AWS, Docker. Value Proposition Built for the long run We hire for the company, not just a project - looking for passion driven engineers who want to grow with Upside over time Small teams, real accountability. 3-9 people per engagement. We're small by design. That means your decisions carry weight and you are visible. Mission-critical work: We handle complex  projects that move the needle for international brands. Our clients are scaling companies, established international brands, and large institutions. The systems you build will be under real load, with real stakes. Real Ownership: You take part in the decision making process on technology and implementation..You’re empowered to take initiative, experiment, and drive solutions that create real impact. No Micromanagement: We trust you to own your work and deliver outcomes - no unnecessary oversight. Collaborative R&D: Contribute to targeted Open-source projects and internal AI research. Growth through challenges: Complex problems and direct client exposure means you’ll grow by action. Applied AI as a first-class discipline. We don't bolt AI onto projects as an afterthought. You'll identify where it genuinely moves the needle and lead the implementation - on client work and on our own open-source tooling. The tools you want. If something makes you faster or sharper, we want you using it. Transparent progression path. We have defined engineering levels with clear criteria - you'll know exactly what each role looks like, and what it takes to get from one to the other. No ambiguity, no waiting for someone above you to move on If you didn't find all the information you were looking for, have a look at our handbook - it covers a variety of different matters that could be important at this stage. If there's anything else we did not mention that you're interested in - share your thoughts with us careers@upsidelab.io Compensation & Location Salary: Senior Engineer: 20 800 - 25 900 PLN net + VAT Lead Engineer: >25 900 PLN net + VAT Location: Office in Kraków, hybrid, fully-remote.

🏢 Summary: Senior Backend Engineer responsible for designing, building, and maintaining production-grade backend systems that power AI-driven business automation. The role covers full ownership from system design to deployment, focusing on scalable, reliable distributed systems and cloud infrastructure. This is a Warsaw-based, office role with strong emphasis on technical leadership and AI-supported development workflows. 🗂️ Requirements: Senior-level experience in backend engineering on production systems, Strong Python programming skills, Experience with distributed systems concepts, Experience with cloud platforms (AWS, Azure, or similar), Knowledge of SQL and NoSQL databases, Ability to design, implement, and deliver systems to production, Strong written and spoken communication skills, Regular use of AI tools in development workflows 📃 Skills: Python, AWS, Azure, SQL, NoSQL, DistributedSystems, Concurrency, AsynchronousProcessing, APIs, Cloud, GitHubCopilot, OpenAI, Claude, TypeScript 🏢 Description: 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.

🏢 Summary: Senior Backend Engineer role focused on designing, shipping, and owning production-grade backend systems for enterprise AI software. The position requires turning ambiguous problems into scalable architectures and maintaining reliability, performance, and observability in production. It is a product engineering role with full ownership from system design to rollout. 🗂️ Requirements: Senior-level backend engineering experience in production systems, Strong Python proficiency, Experience designing distributed systems, Knowledge of concurrency and async processing, Experience with failure handling and data consistency, Hands-on cloud experience (AWS or Azure), Experience with SQL and NoSQL databases, Ability to design data models and system boundaries, Experience building and maintaining APIs and backend services, Production experience with observability and performance tuning, Ability to write technical specifications and architecture documentation, Experience using AI tools in engineering workflows 📃 Skills: Python, AWS, Azure, SQL, NoSQL, APIs, DistributedSystems, Concurrency, Async, Observability, LLM, TypeScript 🏢 Description: About Shelf Shelf builds software that helps enterprises make AI work in the real world. We care about the hard part: reliable systems, clear operational logic, and production-grade engineering that makes AI useful instead of brittle. Job Description: This role is for a senior backend engineer who can own important systems, not just implement tickets. You will take ambiguous problems, design the right backend approach, ship it, and keep it healthy in production. We want someone who is strong technically, communicates clearly, and has the judgment to make systems simpler, safer, and easier to evolve over time. This is a product engineering role with real ownership from system design through production. Location – Warsaw, work from the office What You Will Own Design and ship backend services, APIs, data flows, and background processing for production systems. Turn vague requirements into concrete technical plans, trade-offs, and execution. Own services after launch: reliability, observability, performance, and incident follow-through. Make sound decisions around system boundaries, data models, interfaces, and scaling paths. Write clear technical specs, architecture notes, and diagrams when they help the team move faster. Work closely with product, frontend, and platform engineers to deliver end-to-end outcomes. Improve engineering leverage with AI tooling, automation, and internal workflows rather than using AI as a gimmick. Raise the quality bar through code review, design review, and pragmatic technical leadership. What Strong Performance Looks Like You reliably move important backend work forward without waiting to be tightly managed. Your systems are easier to operate and easier to change because of your design decisions. You communicate trade-offs clearly and make the team around you more effective. You use AI tools well: to accelerate analysis, implementation, debugging, writing, and repetitive work, while keeping a high verification bar. What We Are Looking For Strong senior-level backend engineering experience in production systems. Strong Python skills and the ability to design clean, maintainable backend code. Good distributed systems judgment: concurrency, failure handling, data consistency, async work, and service boundaries. Hands-on cloud experience in AWS, Azure, or a similar environment. Comfort with SQL and NoSQL systems, schema design, and performance tuning. Ability to go from problem statement to design to production rollout with real ownership. Clear written and verbal communication. You can explain systems, trade-offs, and incidents without hiding behind jargon. AI-native working style. You already use AI tools in your daily engineering workflow and want to keep pushing that further. Strong Plus Experience with LLM-backed systems, search, retrieval, AI infrastructure, or data-heavy pipelines. Working knowledge of TypeScript or the ability to contribute across the stack when needed. Experience shaping technical direction for other engineers, even without formal management responsibility. How We Evaluate Fit We care more about ownership, systems judgment, and learning velocity than a perfect keyword match to our stack. If you are the kind of engineer who can take a messy problem and turn it into a strong production system, we want to talk. What Shelf Offers: B2B contract. Company Stock Options. Hardware: MacBook Pro. Modern technical stack . Develop open-source software . GitHub Copilot subscription. Access to Claude Code, OpenAI Codex, TypingMind, and MCP Servers. Why Shelf: Our Leadership Team has deep knowledge management and AI domain expertise and enterprise SaaS background to execute this plan We love our customers and our customers love us. Ask a Shelf customer why, and they’ll tell you it’s because of our innovative capabilities, rock-solid reliability, they truly enjoy working with our people, but most of all – it’s the improvements they see in their business KPIs. We have raised over $60 million in funding and our investors include Tiger Global, Insight Partners, Connecticut Innovations, and others We have high velocity growth powered by the most innovative product in our category, 3X growth for 3 years in a row We now have over 100 employees in multiple U.S. states and European countries, and we have ambitious hiring goals over the next few months

🏢 Summary: Senior Software Engineer role focused on designing and delivering new features and PoCs end-to-end on a large-scale SaaS and data platform. The position emphasizes backend development in Python, extending a mature system, and leveraging AI/LLM tools to accelerate development and improve engineering workflows. Fully remote with high ownership and impact on product direction. 🗂️ Requirements: 7+ years of Software Engineering experience, Strong experience with Python, Experience with Django, Experience building large-scale production systems, Experience designing and maintaining REST APIs, Strong understanding of distributed systems, Strong understanding of backend architecture, Daily practical use of AI tools and LLMs in development workflows, Experience with cloud environments, Ability to independently design and deliver end-to-end solutions, Professional English proficiency 📃 Skills: Python, Django, REST, API, SaaS, LLM, AI, Cloud, DistributedSystems, Backend 🏢 Description: Does building awesome, innovative products that add up to something meaningful sound like a dream come true? Come join us and make that vision a reality! About We are looking for a product-driven Senior Software Engineer who thrives in fast-paced environments and enjoys turning ideas into practical, user-focused solutions. In this role, you will independently design and deliver new features and PoC end-to-end on top of an existing large-scale SaaS and data platform. Rather than working in a purely greenfield environment, you will extend and evolve a mature platform with new capabilities, focusing on speed, usability, and real customer value. A key part of this role is the daily use of AI and LLM-based tools to accelerate development workflows, prototyping, research, testing, and delivery. We are looking for someone who not only uses AI tools effectively but also understands how to integrate AI reasoning and automation into modern software engineering practices. Responsibilities Independently design, prototype, and deliver new features and PoCs end-to-end Translate product ideas into scalable and user-focused backend solutions Validate technical feasibility and make pragmatic architectural decisions Use AI tools, coding copilots, and LLM-based workflows to accelerate development, experimentation, and delivery Build and maintain scalable backend services and REST APIs using Python (preferably Django) Collaborate closely with Product, Design, and Engineering teams to shape and refine new features Contribute to engineering quality through code reviews, technical guidance, and knowledge sharing Continuously explore and introduce practical AI-driven workflows that improve engineering productivity and delivery speed Our offer Competitive salary on B2B contract Fully remote position Real impact and independence at work Individual career path Work-life balance A non-corporate atmosphere where innovation, personal growth, and teamwork thrive 100+ smart, curious & ambitious engineers What you bring 7+ years of experience as a Software Engineer Strong experience with Python and preferably Django Experience building and maintaining large-scale production systems and REST APIs Strong understanding of distributed systems and modern backend architecture Demonstrated daily use of AI tools and LLMs in real engineering workflows (e.g. code generation, prototyping, refactoring, testing, documentation, automation) Experience integrating with complex platforms and cloud environments Ability to independently deliver solutions with minimal supervision Strong product mindset and focus on solving real user problems Excellent communication and collaboration skills across Product, Design, and Engineering teams Curiosity, ownership, and passion for learning and experimenting with new technologies Professional level of English Nice to Have Experience mentoring or coaching engineers Experience working with data products and related scalability challenges Experience promoting AI-driven engineering practices and helping teams adopt modern AI workflows Benefits International Projects Small Teams Flat Structure Friendly Atmosphere Flexible Hours Individual Career Path We want your TALENT! Don’t hesitate and APPLY! We are happy to tell you more details about this position in a phone call. Our recruitment process is very fast and straightforward to ensure a great experience from the first interview to joining your dream team!