🏢 Summary: Backend Engineer role focused on building and scaling the Lightning AI platform across APIs, CLI, billing, security, and integrations using Go. The position involves end-to-end feature ownership, improving system performance and reliability, and driving technical direction in a cloud-based SaaS environment. The role emphasizes software quality, automation, and scalable architecture for AI-driven products. 🗂️ Requirements: Extensive experience with Go development, Experience building and scaling APIs and backend systems, Experience with CLI development, Experience with billing systems integration, Experience implementing security protocols, Experience with cloud platforms (AWS, GCP, or Azure), Experience with containerization technologies, Knowledge of system design and scalable architectures, Experience with test automation and continuous delivery, Experience working in SaaS environments 📃 Skills: Go, Golang, API, CLI, AWS, GCP, Azure, Docker, Kubernetes, SaaS, CI/CD, Testing, Cloud, Architecture, Security 🏢 Description: Who We Are Lightning AI is the company behind PyTorch Lightning. Founded in 2019, we build an end-to-end platform for developing, training, and deploying AI systems—designed to take ideas from research to production with less friction. Through our merger with Voltage Park, a neocloud and AI Factory, Lightning AI combines developer-first software with cost-efficient, large-scale compute. Teams get the tools they need for experimentation, training, and production inference, with security, observability, and control built in. We serve solo researchers, startups, and large enterprises. Lightning AI operates globally with offices in New York City, San Francisco, Seattle, and London, and is backed by Coatue, Index Ventures, Bain Capital Ventures, and Firstminute. Our Values Move Fast: We act with speed and precision, breaking down big challenges into achievable steps. Focus: We complete one goal at a time with care, collaborating as a team to deliver features with precision. Balance: Sustained performance comes from rest and recovery. We ensure a healthy work-life balance to keep you at your best. Craftsmanship: Innovation through excellence. Every detail matters, and we take pride in mastering our craft. Minimal: Simplicity drives our innovation. We eliminate complexity through discipline and focus on what truly matters. What we're looking for We are looking for a Backend Engineer to work on developing and scaling the Lightning AI platform from the frontend, CLI, and API, to billing, security, and integrations. We want someone who can take ownership of key features and drive development from end to end while collaborating with a super-smart team of engineers, product managers, and designers. Here, you'll build from proof of concept to release with a focus on speed, quality, and iteration. This is an opportunity to create groundbreaking technology that will transform the machine-learning ecosystem!You will be joining the Blue Squad and report to our Director of Engineering. This is a hybrid role based in our Bay Area office with in-office requirements of 2 days per week. The salary range for this role is $120,000 - $250,000. What you'll do Write readable/testable/efficient code in Go (Golang). Master our technology stack to deliver new features, improve system stability, and increase overall performance. Partner with engineering and product leaders on developing the Lightning product while using your experience to set the technical direction for large projects. Evaluate, strengthen, and document technical architecture, tools, and processes. Champion software quality, implement automation, drive continuous delivery, and reduce time to production while proactively reducing technical debt. Mentor and coach engineers on system design, operating in high uncertainty, and problem-solving to create a supportive, inclusive environment where each engineer can grow. What you'll need Extensive experience writing efficient, maintainable code in Go. Familiarity with best practices in testing, readability, and optimization is essential. Broad knowledge of backend and frontend systems, with experience building and scaling APIs, CLI tools, billing systems, and security protocols. Exposure to frontend frameworks is a plus. Experience with cloud platforms like AWS, GCP, or Azure and designing systems that are reliable, performant, and scalable. Familiarity with containerization (Docker, Kubernetes) is a strong advantage. Proven ability to take ownership of key features and drive end-to-end development Commitment to software quality, test automation, and continuous delivery. Experience proactively managing technical debt and speeding up time to production. Hands-on experience as a backend or product engineer in a SaaS technology company Communication and collaboration with engineers, product managers, and designers Ability to operate in high uncertainty and rapidly changing environments Benefits and Perks We offer competitive base salaries and equity with a 25% one year cliff and monthly vesting thereafter. For our international employees, we work with our EOR to pay you in your local currency and provide equitable benefits across the globe. In the US, we offer: Medical, dental and vision Life and AD&D insurance Flexible paid time off including winter closure Paid family leave benefits $500 one time home office stipend $1,000 annual learning & development stipend 100% Citibike membership (NYC only) $45/month gym membership Additional various medical and mental health services At Lightning AI, we are committed to fostering an inclusive and diverse workplace. We believe that diverse teams drive innovation and create better products. We provide equal employment opportunities to all employees and applicants without regard to race, color, religion, gender, sexual orientation, gender identity, national origin, age, disability, veteran status, or any other protected characteristic. We are dedicated to building a culture where everyone can thrive and contribute to their fullest potential.

🏢 Summary: Backend Engineer role focused on building and scaling the Lightning AI platform across APIs, CLI, billing, security, and integrations, with end-to-end ownership of features from concept to production. The position emphasizes high-quality Go development, system performance, and scalable cloud architecture in a fast-paced AI environment. 🗂️ Requirements: Extensive experience developing in Go, Experience building and scaling APIs and backend systems, Experience with cloud platforms (AWS, GCP, or Azure), Experience with containerization technologies, Strong knowledge of system design and scalable architectures, Experience implementing test automation and continuous delivery, Hands-on experience in a SaaS product environment, Ability to own features end-to-end and drive technical decisions 📃 Skills: Go, Golang, AWS, GCP, Azure, Docker, Kubernetes, API, CLI, SaaS 🏢 Description: Who We Are Lightning AI is the company behind PyTorch Lightning. Founded in 2019, we build an end-to-end platform for developing, training, and deploying AI systems—designed to take ideas from research to production with less friction. Through our merger with Voltage Park, a neocloud and AI Factory, Lightning AI combines developer-first software with cost-efficient, large-scale compute. Teams get the tools they need for experimentation, training, and production inference, with security, observability, and control built in. We serve solo researchers, startups, and large enterprises. Lightning AI operates globally with offices in New York City, San Francisco, Seattle, and London, and is backed by Coatue, Index Ventures, Bain Capital Ventures, and Firstminute. Our Values Move Fast: We act with speed and precision, breaking down big challenges into achievable steps. Focus: We complete one goal at a time with care, collaborating as a team to deliver features with precision. Balance: Sustained performance comes from rest and recovery. We ensure a healthy work-life balance to keep you at your best. Craftsmanship: Innovation through excellence. Every detail matters, and we take pride in mastering our craft. Minimal: Simplicity drives our innovation. We eliminate complexity through discipline and focus on what truly matters. What we're looking for We are looking for a Backend Engineer to work on developing and scaling the Lightning AI platform from the frontend, CLI, and API, to billing, security, and integrations. We want someone who can take ownership of key features and drive development from end to end while collaborating with a super-smart team of engineers, product managers, and designers. Here, you'll build from proof of concept to release with a focus on speed, quality, and iteration. This is an opportunity to create groundbreaking technology that will transform the machine-learning ecosystem!You will be joining the Blue Squad and report to our Director of Engineering. This is a hybrid role based in our Bay Area office with in-office requirements of 2 days per week. The salary range for this role is $120,000 - $250,000. What you'll do Write readable/testable/efficient code in Go (Golang). Master our technology stack to deliver new features, improve system stability, and increase overall performance. Partner with engineering and product leaders on developing the Lightning product while using your experience to set the technical direction for large projects. Evaluate, strengthen, and document technical architecture, tools, and processes. Champion software quality, implement automation, drive continuous delivery, and reduce time to production while proactively reducing technical debt. Mentor and coach engineers on system design, operating in high uncertainty, and problem-solving to create a supportive, inclusive environment where each engineer can grow. What you'll need Extensive experience writing efficient, maintainable code in Go. Familiarity with best practices in testing, readability, and optimization is essential. Broad knowledge of backend and frontend systems, with experience building and scaling APIs, CLI tools, billing systems, and security protocols. Exposure to frontend frameworks is a plus. Experience with cloud platforms like AWS, GCP, or Azure and designing systems that are reliable, performant, and scalable. Familiarity with containerization (Docker, Kubernetes) is a strong advantage. Proven ability to take ownership of key features and drive end-to-end development Commitment to software quality, test automation, and continuous delivery. Experience proactively managing technical debt and speeding up time to production. Hands-on experience as a backend or product engineer in a SaaS technology company Communication and collaboration with engineers, product managers, and designers Ability to operate in high uncertainty and rapidly changing environments Benefits and Perks We offer competitive base salaries and equity with a 25% one year cliff and monthly vesting thereafter. For our international employees, we work with our EOR to pay you in your local currency and provide equitable benefits across the globe. In the US, we offer: Medical, dental and vision Life and AD&D insurance Flexible paid time off including winter closure Paid family leave benefits $500 one time home office stipend $1,000 annual learning & development stipend 100% Citibike membership (NYC only) $45/month gym membership Additional various medical and mental health services At Lightning AI, we are committed to fostering an inclusive and diverse workplace. We believe that diverse teams drive innovation and create better products. We provide equal employment opportunities to all employees and applicants without regard to race, color, religion, gender, sexual orientation, gender identity, national origin, age, disability, veteran status, or any other protected characteristic. We are dedicated to building a culture where everyone can thrive and contribute to their fullest potential.

🏢 Summary: Frontend Engineer role focused on building and scaling the UI and frontend infrastructure of an AI platform using React and Redux. The position involves end-to-end feature ownership, improving system stability and performance, and driving technical direction for large frontend projects. This hybrid role requires collaboration with cross-functional teams to deliver high-quality SaaS product features. 🗂️ Requirements: Proficiency in React, Proficiency in JavaScript, Proficiency in TypeScript, Strong understanding of software engineering principles and lifecycle, Hands-on frontend experience in a SaaS company, Experience with end-to-end feature development, Ability to define and improve frontend architecture, Experience implementing automated testing and continuous delivery 📃 Skills: React, Redux, JavaScript, TypeScript, SaaS, CI/CD, Testing, Frontend 🏢 Description: Who We Are Lightning AI is the company behind PyTorch Lightning. Founded in 2019, we build an end-to-end platform for developing, training, and deploying AI systems—designed to take ideas from research to production with less friction. Through our merger with Voltage Park, a neocloud and AI Factory, Lightning AI combines developer-first software with cost-efficient, large-scale compute. Teams get the tools they need for experimentation, training, and production inference, with security, observability, and control built in. We serve solo researchers, startups, and large enterprises. Lightning AI operates globally with offices in New York City, San Francisco, Seattle, and London, and is backed by Coatue, Index Ventures, Bain Capital Ventures, and Firstminute. Our Values Move Fast: We act with speed and precision, breaking down big challenges into achievable steps. Focus: We complete one goal at a time with care, collaborating as a team to deliver features with precision. Balance: Sustained performance comes from rest and recovery. We ensure a healthy work-life balance to keep you at your best. Craftsmanship: Innovation through excellence. Every detail matters, and we take pride in mastering our craft. Minimal: Simplicity drives our innovation. We eliminate complexity through discipline and focus on what truly matters. What We're Looking For We are looking for a frontend engineer to help us develop and scale the UI and frontend infrastructure of the Lightning AI platform. We want someone who can take ownership of key features and drive development from end to end while collaborating with a super-smart team of engineers, product managers, and designers. Here, you'll build from proof of concept to release with a focus on speed, quality, and iteration. With over 10,000 organizations building with Lightning, you'll have a unique opportunity to impact how the world builds and deploys AI to production. This is a hybrid role based in our San Francisco office with in-office requirements of 2 days per week. The salary range for this role is $120,000 - $250,000. What You'll Do Write readable/testable/efficient code in React and Redux and master our technology stack to deliver new features, improve system stability, and increase overall performance. Partner with engineering and product leaders on developing the user interface and frontend infrastructure while using your experience to set the technical direction for large projects. Evaluate, strengthen, and document technical architecture, tools, and processes. Champion software quality, implement automation, drive continuous delivery, and reduce time to production while proactively reducing technical debt. Mentor and coach engineers on system design, operating in high uncertainty, and problem-solving to create a supportive, inclusive environment in which each engineer can grow. What You'll Need Proficiency in React, javascript and typescript. Strong understanding of software engineering principles and lifecycle. Hands-on experience as a frontend engineer in a SaaS technology company Proven ability to take ownership of key features and drive end-to-end development Communication and collaboration with engineers, product managers, and designers Ability to operate in high uncertainty and rapidly changing environments Benefits and Perks We offer competitive base salaries and equity with a 25% one year cliff and monthly vesting thereafter. For our international employees, we work with our EOR to pay you in your local currency and provide equitable benefits across the globe. In the US, we offer: Medical, dental and vision Life and AD&D insurance Flexible paid time off including winter closure Paid family leave benefits $500 one time home office stipend $1,000 annual learning & development stipend 100% Citibike membership (NYC only) $45/month gym membership Additional various medical and mental health services At Lightning AI, we are committed to fostering an inclusive and diverse workplace. We believe that diverse teams drive innovation and create better products. We provide equal employment opportunities to all employees and applicants without regard to race, color, religion, gender, sexual orientation, gender identity, national origin, age, disability, veteran status, or any other protected characteristic. We are dedicated to building a culture where everyone can thrive and contribute to their fullest potential.

🏢 Summary: Frontend Engineer role focused on building and scaling the UI and frontend infrastructure of an AI platform, driving end-to-end feature development from concept to production. The position emphasizes high-quality React-based development, technical ownership, and improving performance, stability, and delivery processes in a SaaS environment. Hybrid role based in San Francisco with impact on AI tools used by thousands of organizations. 🗂️ Requirements: Proficiency in React, Proficiency in JavaScript, Proficiency in TypeScript, Strong understanding of software engineering principles and lifecycle, Hands-on frontend engineering experience in a SaaS company, Experience delivering end-to-end frontend features, Ability to collaborate with engineers, product managers, and designers, Ability to work in high-uncertainty, fast-changing environments 📃 Skills: React, Redux, JavaScript, TypeScript, SaaS, CI/CD, Automation 🏢 Description: Who We Are Lightning AI is the company behind PyTorch Lightning. Founded in 2019, we build an end-to-end platform for developing, training, and deploying AI systems—designed to take ideas from research to production with less friction. Through our merger with Voltage Park, a neocloud and AI Factory, Lightning AI combines developer-first software with cost-efficient, large-scale compute. Teams get the tools they need for experimentation, training, and production inference, with security, observability, and control built in. We serve solo researchers, startups, and large enterprises. Lightning AI operates globally with offices in New York City, San Francisco, Seattle, and London, and is backed by Coatue, Index Ventures, Bain Capital Ventures, and Firstminute. Our Values Move Fast: We act with speed and precision, breaking down big challenges into achievable steps. Focus: We complete one goal at a time with care, collaborating as a team to deliver features with precision. Balance: Sustained performance comes from rest and recovery. We ensure a healthy work-life balance to keep you at your best. Craftsmanship: Innovation through excellence. Every detail matters, and we take pride in mastering our craft. Minimal: Simplicity drives our innovation. We eliminate complexity through discipline and focus on what truly matters. What We're Looking For We are looking for a frontend engineer to help us develop and scale the UI and frontend infrastructure of the Lightning AI platform. We want someone who can take ownership of key features and drive development from end to end while collaborating with a super-smart team of engineers, product managers, and designers. Here, you'll build from proof of concept to release with a focus on speed, quality, and iteration. With over 10,000 organizations building with Lightning, you'll have a unique opportunity to impact how the world builds and deploys AI to production. This is a hybrid role based in our San Francisco office with in-office requirements of 2 days per week. The salary range for this role is $120,000 - $250,000. What You'll Do Write readable/testable/efficient code in React and Redux and master our technology stack to deliver new features, improve system stability, and increase overall performance. Partner with engineering and product leaders on developing the user interface and frontend infrastructure while using your experience to set the technical direction for large projects. Evaluate, strengthen, and document technical architecture, tools, and processes. Champion software quality, implement automation, drive continuous delivery, and reduce time to production while proactively reducing technical debt. Mentor and coach engineers on system design, operating in high uncertainty, and problem-solving to create a supportive, inclusive environment in which each engineer can grow. What You'll Need Proficiency in React, javascript and typescript. Strong understanding of software engineering principles and lifecycle. Hands-on experience as a frontend engineer in a SaaS technology company Proven ability to take ownership of key features and drive end-to-end development Communication and collaboration with engineers, product managers, and designers Ability to operate in high uncertainty and rapidly changing environments Benefits and Perks We offer competitive base salaries and equity with a 25% one year cliff and monthly vesting thereafter. For our international employees, we work with our EOR to pay you in your local currency and provide equitable benefits across the globe. In the US, we offer: Medical, dental and vision Life and AD&D insurance Flexible paid time off including winter closure Paid family leave benefits $500 one time home office stipend $1,000 annual learning & development stipend 100% Citibike membership (NYC only) $45/month gym membership Additional various medical and mental health services At Lightning AI, we are committed to fostering an inclusive and diverse workplace. We believe that diverse teams drive innovation and create better products. We provide equal employment opportunities to all employees and applicants without regard to race, color, religion, gender, sexual orientation, gender identity, national origin, age, disability, veteran status, or any other protected characteristic. We are dedicated to building a culture where everyone can thrive and contribute to their fullest potential.

🏢 Summary: The offer is for a Senior AI Fullstack Engineer to design and deliver production-ready, LLM-powered web applications using modern React and Next.js architecture. The role focuses on building autonomous agents, RAG systems, and AI-driven workflows integrated with enterprise-grade products. It involves end-to-end ownership of scalable AI solutions from architecture to deployment. 🗂️ Requirements: 8+ years experience as consultant or forward deployed engineer, Strong experience with Next.js (App Router), React, TypeScript, Deep understanding of Server and Client Components (RSC), Experience with streaming, caching, revalidation, Server Actions, Experience with Vercel AI SDK, LangGraph or MCP, Experience building RAG systems, Hands-on experience with Anthropic and OpenAI APIs, Experience shipping LLM-powered features to production, Practical experience with prompt engineering and structured outputs, Experience with tool calling and agent workflows, Experience with multi-turn orchestration, Understanding of token economics and context windows, Experience with prompt evaluation methods, Ability to design robust, production-ready AI systems 📃 Skills: Next.js, React, TypeScript, RSC, Vercel, LangGraph, MCP, RAG, Claude, OpenAI, Anthropic, Prompting, Streaming, ServerActions, Agents, APIs 🏢 Description: About the Role At Blazity, we are a team of React.js and Next.js experts building modern, API-first digital products for enterprise clients. We are expanding our AI capabilities—autonomous agents, AI-driven automation, and LLM-powered workflows—and are looking for a Senior AI Fullstack Engineer who can design and ship production-ready AI systems. You will work at the intersection of modern web architecture and generative AI , taking ownership of solutions delivered to real users. Our requirements Must-have Technical Excellence: 8+ years of experience as a consultant / forward deployed engineer Strong experience with Next.js (App Router), React, TypeScript Deep understanding of: Server vs Client Components (RSC) streaming, caching, revalidation, Server Actions Vercel AI SDK / LangGraph / MCP Experience building RAG systems Claude extended thinking / prompt caching / Batch APIs AI Engineering: Proven experience shipping LLM-powered features to production Hands-on with Anthropic / OpenAI APIs (messages, tool use, streaming) Practical experience with: prompt engineering (structured output, few-shot, XML) tool calling / agent workflows multi-turn orchestration Understanding of: token economics (input/output costs, context window) latency vs quality trade-offs Reliability & Quality: Experience with: prompt evaluations (LLM-as-judge, rule-based) handling hallucinations and failure modes Ability to design robust AI systems , not just prototypes Soft Skills: Strong ownership mindset Experience working directly with clients Clear communication and structured thinking (English C1) Ability to make decisions in ambiguous environments Nice-to-have: What You Will Do Ship Production Apps: Build scalable web applications using Next.js (App Router) and TypeScript , ensuring high performance and clean architecture. Engineer AI Workflows: Develop and orchestrate LLM-powered features using Anthropic and OpenAI APIs, focusing on tool use and streaming. Agentic Orchestration: Design autonomous agent loops and multi-turn workflows, knowing when to use a structured pipeline versus a dynamic agent. Optimize & Evaluate: Manage token economics (pricing, context windows) and implement prompt evaluations (LLM-as-judge, rule-based) to ensure system reliability. Collaborate: Work directly with senior engineers, founders, and client teams to shape AI capabilities from concept to production. What we offer B2B: 120 – 180 PLN/h + VAT 🔥 100% remote (Poland) 29 paid vacation days Private healthcare + sports card High-impact work on real AI systems

🏢 Summary: Fullstack/Web Engineer role focused on building and optimizing high-performance, real-time user-facing features for a large-scale social platform. The position emphasizes frontend excellence while contributing across the stack, including scalable backend systems and real-time analytics. You will own features end-to-end, driving architecture, performance, and reliability for globally deployed products. 🗂️ Requirements: 2+ years web development experience, Expertise in TypeScript, Expertise in Node.js, Expertise in React or modern web frameworks, Expertise in CSS/SASS, Experience with UI/UX design, Experience optimizing performance and security, Experience building scalable, high-concurrency systems, Backend development experience, Proficiency in Rust, Go, Java, Python, or Scala 📃 Skills: TypeScript, Node.js, React, CSS, SASS, Rust, Go, Java, Python, Scala, HTML, WebSockets, REST, GraphQL, SQL, NoSQL, Testing, CI/CD, Monitoring, Security 🏢 Description: About xAI xAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates.About the Role: We're looking for exceptional Fullstack / Web Engineers that can work across the stack but have a passion for frontend development and a keen eye for design. You'll architect and optimize user-facing features that power real-time conversations for millions worldwide. Dive into cutting-edge technologies and scalable backend systems, collaborating with top-tier talent to push the boundaries of web performance and innovation. You have the ability to thrive in a fast-paced environment, where you proactively tackle high-impact challenges that shape the future of social media—perfect for engineers passionate about crafting seamless, responsive experiences that drive global engagement and redefine digital interaction. Responsibilities: Own and drive features from inception and design to implementation and launch, being the web expert on your team. Build and maintain high-quality, performant products and features, leveraging the most modern and cutting edge web standards, technologies, frameworks, and AI tooling. Responsible for fullstack features, including user dashboards, personalized experiences, content delivery, interactive tools, assessments, and real-time analytics Lead architecture, scalability, and reliability decisions for high-concurrency, low-latency systems. Uphold engineering excellence via testing, monitoring, deployment, and secure data handling. Drive technical/product decisions with teams and deploy global features to maximize user value. Basic Qualifications: 2+ years of web development experience. Expert in TypeScript, Node.js, and modern web frameworks (e.g., React). Expert in modern CSS/SASS Experience in high-quality UI and UX design Proven track record of optimizing applications for performance, security, and offline functionality. Preferred Skills and Experience: 5+ years of experience in a web frontend role, working on a large scale consumer app. Experience with backend development, proficiency in one or more of the following: Rust, Go, Java, Python, Scala. Compensation and Benefits: $180,000 - $440,000 USD Base salary is just one part of our total rewards package at xAI, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks.xAI is an equal opportunity employer. For details on data processing, view our Recruitment Privacy Notice.

🏢 Summary: Frontend-leaning Fullstack Engineer role building high-scale SaaS systems with modern React/Next.js frontends and Node.js/NestJS backends, heavily leveraging AI tools and automation. You will design APIs, async systems, and event-driven architectures, integrate external services, and ship MVPs to production with ownership and speed. The role emphasizes AI-driven workflows, rapid experimentation, and scalable, production-ready systems. 🗂️ Requirements: 2.5+ years professional full-stack experience, Strong React.js and Next.js skills, Backend experience with Node.js (NestJS preferred), Experience integrating external APIs (auth, pagination, retries, rate limits), Hands-on experience with modern AI tools (OpenAI, Claude, Cursor), Strong SQL skills (PostgreSQL preferred), Experience with async processing, queues, background jobs, Understanding of reliable systems (error handling, retries, observability), Fluent English and Polish 📃 Skills: React, Next.js, Node.js, NestJS, SQL, PostgreSQL, REST, WebSockets, OpenAI, Claude, Cursor, LavinMQ, BullMQ, Kafka, AWS, GCP, Fly.io, DigitalOcean, BigQuery, ClickHouse, Golang, Elixir, Rust, gRPC, GitLabCI 🏢 Description: At Web Impact, we’re more than just an email marketing agency and digital solutions provider. We build cutting-edge, socially impactful products that redefine how businesses operate in the digital world. We’re looking for a frontend-leaning Fullstack Engineer who enjoys building complex systems, integrating external services, and leveraging AI tools to speed up development and automate workflows. If you’re excited about combining modern frontend development with AI-driven workflows and automation tools like Claude Code, Cursor, and LLM frameworks , this one is for you. What You’ll Do Develop and contribute to end-to-end features across SaaS products and internal tools, collaborating with senior engineers on architecture and implementation decisions. Build modern, high-performance frontends using Next.js and React.js Develop scalable backend services using Node.js / NestJS Design and integrate APIs (REST, WebSockets, external services) Build and maintain automation workflows and background jobs Work with async systems, queues, and event-driven architectures Integrate third-party services with real-world constraints (rate limits, retries, auth flows) Use AI tools to improve development speed, testing, and automation Collaborate directly with product, data, and leadership teams Build MVPs, proof-of-concepts, and new product ideas from scratch Rapidly validate business ideas through experimentation and iteration Help evolve successful prototypes into production-ready systems AI & Automation This role includes working with modern AI tooling and automation systems, with a strong focus on speed, ownership, and execution : Using tools like Claude Code, Cursor, and OpenAI SDK in daily development Building AI-driven workflows and integrations quickly and iteratively Automating repetitive processes (data handling, content, integrations) Applying LLMs in production with a pragmatic, results-first approach Taking ownership of problems - from idea to production Shipping fast, testing in real conditions, and iterating based on outcomes Being accountable for delivery - not just writing code, but making things work end-to-end Prioritizing execution over perfection - speed is key What We’re Looking For 2,5+ years of professional full-stack experience Strong frontend skills in React.js / Next.js Backend experience with Node.js (NestJS preferred) Experience integrating external APIs (auth, pagination, retries, rate limits) Hands-on experience with modern AI tools (OpenAI, Claude, Cursor, etc.) Good SQL skills (PostgreSQL preferred) Experience working with async processing, queues, and background jobs Understanding of building reliable systems (error handling, retries, observability) Strong communication skills and ability to work cross-functionally Fluent in English and Polish Nice to Have Experience with Rust (async, Tokio, Axum) Experience with Elixir (Phoenix LiveView, GenServer) Understanding of distributed systems and architectures Experience with multi-region deployments and geo-distributed infrastructure Experience building systems with high parallelism (a large number of workers processing jobs concurrently) Familiarity with distributed databases and data consistency trade-offs Experience with multi-tenancy architectures (tenant isolation, scaling strategies) Experience working with high-throughput event pipelines Our Tech Stack Frontend: Next.js, React.js Backend: Node.js, NestJS, Golang, Elixir, Rust Data: PostgreSQL, BigQuery, ClickHouse Infra: AWS, Fly.io , Google Cloud, DigitalOcean Queues & Workers: LavinMQ, BullMQ, Kafka CI/CD: GitLab CI AI/ML & Automation: Proprietary GenAI models, OpenAI, Claude, internal tooling Integrations: REST, gRPC, WebSockets, external APIs with rate limits Why Join Us? Work on high-scale SaaS systems processing hundreds of millions of events daily , with real-time pipelines and data-heavy workloads. Ownership from day one - influence architecture, technology choices, and product direction. Collaborate with world-class engineers, AI specialists, and PMs. Innovation-first culture - explore cutting-edge frameworks and architectures. Fast execution, minimal bureaucracy, no unnecessary meetings Opportunity to work with modern AI tooling in production Competitive senior-level compensation and career growth. Social impact - contribute to automation products that empower businesses and communities. Our Streamlined Hiring Process Initial call Technical deep dive with our team Decision

🏢 Summary: Senior / Staff Full Stack Engineer role focused on building and scaling an AI-driven product platform in a fully remote setup. The position involves developing React/TypeScript frontend experiences and Python-based backend APIs to support document processing, retrieval systems, and structured AI/ML outputs. The engineer will integrate frontend, backend, and AI workflows into a reliable, testable product experience. 🗂️ Requirements: 5+ years full stack engineering experience, Strong Python backend API development experience, Strong React and TypeScript production experience, Experience with modern API frameworks (e.g. FastAPI), Experience designing and consuming API contracts and structured JSON, Experience with asynchronous workflows and background jobs, Testing experience covering edge cases and API behavior, Understanding of AI/ML product workflows 📃 Skills: Python, React, TypeScript, FastAPI, API, JSON, AI, ML, LLM, OpenAI, Gemini, Anthropic, Embeddings, Vector, Firebase, Firestore, GCP, CloudRun, CloudSQL, Neo4j 🏢 Description: We are looking for a Senior / Staff Full Stack Engineer with strong Python and React experience to build and scale an AI driven product platform in a fully remote setup. The role focuses on frontend experiences, backend APIs, document processing, retrieval systems, and structured AI / ML outputs. ✅ Your responsibilities: Building frontend experiences in React and TypeScript for evidence review, workflow status, recommendations, and decision outputs. Developing backend APIs in Python, ideally with FastAPI, for document upload, asynchronous processing, job status, retries, partial success, and structured results. Connecting frontend, backend, data workflows, retrieval systems, and AI generated outputs into a reliable product experience. Building product features that make AI outputs easier to inspect through source references, confidence signals, warnings, and clear error states. Working with structured data, documents, tables, financial metrics, and normalized evidence flows. Writing tests around API contracts, edge cases, error cases, and realistic user workflows. 🧠 Our requirements: 5+ years of professional full stack engineering experience. Strong experience with Python and backend API development. Strong experience with React and TypeScript in production applications. Experience with modern API frameworks, ideally FastAPI or similar. Understanding of AI / ML product workflows or strong interest in building software around AI outputs. Experience designing and consuming API contracts, schemas, and structured JSON payloads. Comfort with asynchronous workflows, background jobs, retries, partial failures, and user visible process status. Good testing habits, especially around edge cases, failure cases, and API behavior. ⭐ Nice to Have: Experience with AI / ML product workflows, including retrieval systems, embeddings, vector search, LLM based applications, or LLM APIs such as OpenAI, Gemini, Anthropic/Claude. Experience with data heavy products, including data workflows, document processing, data normalization, or working with structured evidence. Experience with cloud and data infrastructure, ideally Firebase, Firestore, Google Cloud Platform, Cloud Run, Cloud SQL, vector search, or Neo4j. 🌟 What we offer: 100% remote work Opportunity to work on modern ML/AI infrastructure Private healthcare and Multisport Life insurance Real influence on technical decisions and architecture Exposure to cutting-edge technologies Collaborative and supportive team environment

🏢 Summary: Senior or Staff Backend Engineer role focused on architecting and scaling AI-native backend systems for a modern accounting platform. The position involves designing distributed services, building high-performance APIs, and establishing engineering standards to support rapid, reliable product delivery. You will work closely with Product, AI, and Operations teams to develop agentic systems and scalable data pipelines. 🗂️ Requirements: 5–10+ years of backend engineering experience, Proven experience designing, building, and operating production backend systems at scale, Strong expertise in API design, Strong expertise in data modelling, Deep understanding of distributed systems trade-offs, Hands-on experience with AWS or GCP in production, Practical experience with CI/CD in high-frequency deployment environments, Experience implementing testing and deployment strategies, Strong knowledge of observability practices, Experience participating in on-call rotations 📃 Skills: TypeScript, Node.js, React, AWS, GCP, Terraform, PostgreSQL, OpenAI, Azure, CI/CD, APIs, DistributedSystems 🏢 Description: ABOUT THE ROLE We're looking for a Senior or Staff Backend Engineer to own and evolve our backend services as we scale. This is a broad, high-impact role — you'll architect new features, build the systems that underpin our core product, and set the engineering standards that shape how the whole team works. The focus is on building a modern, AI-native developer experience. That means working closely with Product, AI, and Operations teams to design agentic systems, distributed data pipelines, and scalable incident response infrastructure — and doing it in a way that lets the team ship with confidence multiple times a day. WHAT YOU'LL WORK ON Architecture and feature design Partner with Product, AI, and Operations teams to architect new features and complex agentic systems. Make clear architectural trade-offs that balance platform, product, and business goals. Backend services and APIs Build and maintain the backend services and APIs that power the core product. Ensure systems are secure, well-tested, and high performance. Distributed systems Design and implement distributed services to orchestrate data pipelines, automate investigations, and enable incident response at scale. Operational excellence Own operational best practices so the team can ship multiple times a day with confidence. Healthy on-call culture and strong observability are part of what you'll build and maintain. Engineering standards Set the bar for writing, communication, and system design across the team. Your influence will shape how a modern AI-native product is built. WHAT WE LOOK FOR 5–10+ years of backend engineering experience A strong track record designing, building, and operating production backend systems at scale. Deep backend fundamentals Expertise in API design, data modelling, and reasoning about distributed systems trade-offs. You understand the nuances, not just the patterns. AWS or GCP hands-on experience Solid understanding of how infrastructure decisions impact application reliability and performance. You've run things in production, not just designed them. CI/CD in practice Practical experience with testing and deployment strategies in high-frequency shipping environments. Observability and on-call maturity A solid grasp of what good observability looks like and how to build healthy on-call practices that don't burn people out. Bonus Experience at an early-stage or scaling startup. Exposure to modern AI and ML systems. Experience shipping product without a dedicated product manager. TECH STACK TypeScript, React, Node.js, AWS, Terraform, PostgreSQL, OpenAI, Azure AI. The team uses GitHub, Slack, Linear, Figma, and Notion day to day. THE TEAM Small, senior, and in-person. The office is in central Wrocław, next to the main train station. The expectation is 4–5 days a week in the office. Relocation support is available for the right candidate. COMPENSATION & BENEFITS Salary $130,000 – $190,000 USD depending on experience, plus competitive equity. Wellness and commute stipend $100 per month. Hardware Premium hardware provided — MacBook Pro and AirPods. Food Daily in-office lunch and dinner. Time off 20 PTO days plus 9 US public holidays. Relocation Support available for candidates relocating to Wrocław.

🏢 Summary: Senior or Staff Backend Engineer role focused on architecting and scaling AI-native backend services for a modern accounting platform. The position involves designing distributed systems, building secure and high-performance APIs, and establishing engineering standards to support rapid, reliable product delivery. You will work closely with Product, AI, and Operations teams to build scalable data pipelines and incident response infrastructure. 🗂️ Requirements: 5–10+ years of backend engineering experience, Proven experience designing and operating production backend systems at scale, Strong expertise in API design and data modelling, Deep understanding of distributed systems and architectural trade-offs, Hands-on experience with AWS or GCP in production environments, Practical experience with CI/CD pipelines and automated testing, Experience building and maintaining observability and on-call practices 📃 Skills: TypeScript, Node.js, React, AWS, GCP, Terraform, PostgreSQL, OpenAI, Azure, CI/CD, APIs, DistributedSystems, DataModelling, Observability 🏢 Description: ABOUT THE COMPANY We're an applied AI company building an AI-native alternative to legacy accounting software — a market worth tens of billions in annual recurring revenue. Our mission is to help entrepreneurs focus on what matters in their business and life, and to help their accountants become more strategic. We've raised $20M from a group of top-tier investors and have grown ARR 60% month-on-month since our public launch. We now serve thousands of businesses and are expanding our product to serve accountants directly — creating a two-sided platform where both business owners and their accountants use and recommend us. We're at an early but proven stage, moving fast, and building a world-class engineering team in Wrocław to match our ambition. ABOUT THE ROLE We're looking for a Senior or Staff Backend Engineer to own and evolve our backend services as we scale. This is a broad, high-impact role — you'll architect new features, build the systems that underpin our core product, and set the engineering standards that shape how the whole team works. The focus is on building a modern, AI-native developer experience. That means working closely with Product, AI, and Operations teams to design agentic systems, distributed data pipelines, and scalable incident response infrastructure — and doing it in a way that lets the team ship with confidence multiple times a day. WHAT YOU'LL WORK ON Architecture and feature design Partner with Product, AI, and Operations teams to architect new features and complex agentic systems. Make clear architectural trade-offs that balance platform, product, and business goals. Backend services and APIs Build and maintain the backend services and APIs that power the core product. Ensure systems are secure, well-tested, and high performance. Distributed systems Design and implement distributed services to orchestrate data pipelines, automate investigations, and enable incident response at scale. Operational excellence Own operational best practices so the team can ship multiple times a day with confidence. Healthy on-call culture and strong observability are part of what you'll build and maintain. Engineering standards Set the bar for writing, communication, and system design across the team. Your influence will shape how a modern AI-native product is built. WHAT WE LOOK FOR 5–10+ years of backend engineering experience A strong track record designing, building, and operating production backend systems at scale. Deep backend fundamentals Expertise in API design, data modelling, and reasoning about distributed systems trade-offs. You understand the nuances, not just the patterns. AWS or GCP hands-on experience Solid understanding of how infrastructure decisions impact application reliability and performance. You've run things in production, not just designed them. CI/CD in practice Practical experience with testing and deployment strategies in high-frequency shipping environments. Observability and on-call maturity A solid grasp of what good observability looks like and how to build healthy on-call practices that don't burn people out. Bonus Experience at an early-stage or scaling startup. Exposure to modern AI and ML systems. Experience shipping product without a dedicated product manager. TECH STACK TypeScript, React, Node.js, AWS, Terraform, PostgreSQL, OpenAI, Azure AI. The team uses GitHub, Slack, Linear, Figma, and Notion day to day. THE TEAM Small, senior, and in-person. The office is in central Wrocław, next to the main train station. The expectation is 4–5 days a week in the office — this is a deliberate choice, not a compromise. Relocation support is available for the right candidate. COMPENSATION & BENEFITS Salary $130,000 – $190,000 USD depending on experience, plus competitive equity. Wellness and commute stipend $100 per month. Hardware Premium hardware provided — MacBook Pro and AirPods. Food Daily in-office lunch and dinner. Time off 20 PTO days plus 9 US public holidays. Relocation Support available for candidates relocating to Wrocław.