126 to 150 of 191 FastAPI Jobs in the City of London

measures, sensors) -> Offline-first/PWA apps for installers on the move Tech Stack: -> React, TypeScript, Konva, Tailwind -> Node.js, PostGREST, Prisma -> PostgreSQL/PostGIS, Docker, Atlas -> (Sunsetting Python + FastAPI) Requirements for Carbon Emission/Green Tech Start-up | Full Stack Engineer | LDN 2 Days Per Week | £50K - £110K + Healthy Equity -> 2+ years commercial experience -> STEM Background -> React + More ❯

in project delivery : taking ideas from concept to production under tight timelines. Comfort with ambiguity and speed — this is an early-stage, high-autonomy environment. Tech Snapshot Python 3.11+, FastAPI, SQLAlchemy, Alembic, PostgreSQL AWS (IAM, SES, Bedrock) Event-driven architecture, API-first development AI/ML pipelines integrated into core workflows Why This Role Take over a Lead position and More ❯

in project delivery : taking ideas from concept to production under tight timelines. Comfort with ambiguity and speed — this is an early-stage, high-autonomy environment. Tech Snapshot Python 3.11+, FastAPI, SQLAlchemy, Alembic, PostgreSQL AWS (IAM, SES, Bedrock) Event-driven architecture, API-first development AI/ML pipelines integrated into core workflows Why This Role Take over a Lead position and More ❯

of which are Python based. Key Skills Strong Object-Oriented Python Programming Understanding of Algo's and quant models. Excellent database knowledge, including SQL and MongoDB API Frameworks (Flask, FastAPI) Prior experience in energy markets This is a hybrid role requiring 3 days in the office. The salary for the role is up to £110,000 + bonus & benefits. If More ❯

of which are Python based. Key Skills Strong Object-Oriented Python Programming Understanding of Algo's and quant models. Excellent database knowledge, including SQL and MongoDB API Frameworks (Flask, FastAPI) Prior experience in energy markets This is a hybrid role requiring 3 days in the office. The salary for the role is up to £110,000 + bonus & benefits. If More ❯

enterprise background to deliver robust, business-critical systems that support trading operations. What you’ll bring Strong Python (3.10+) development experience Enterprise-level experience building and scaling complex systems FastAPI, RabbitMQ/Dramatiq, and Azure expertise Solid database background (SQL & MongoDB) Front office and commodities trading domain knowledge Why join? Up to £110k base + hefty bonus + strong benefits More ❯

Engineer (3+ years’ experience) to take ownership of core backend systems end-to-end, from infrastructure to database design. Ideal Profile: Strong experience with Python and SQL Familiarity with FastAPI , Pydantic , and PostgreSQL Bonus: experience with lower-level languages such as Rust Role Details: Compensation: £80K–£130K + equity (0.1–0.3%) Location: On-site in London, 4/5 days More ❯

Engineer (3+ years’ experience) to take ownership of core backend systems end-to-end, from infrastructure to database design. Ideal Profile: Strong experience with Python and SQL Familiarity with FastAPI , Pydantic , and PostgreSQL Bonus: experience with lower-level languages such as Rust Role Details: Compensation: £80K–£130K + equity (0.1–0.3%) Location: On-site in London, 4/5 days More ❯

of a 7-person engineering team, working end-to-end on the core product: from scaling AI-driven features to building beautifully simple interfaces for complex workflows. 💻 Tech: Python, FastAPI, Postgres, ElasticSearch, RabbitMQ, React, LLMs (We are open to engineers from other language backgrounds) 💸 £80-£110k + strong equity 📍 London (4 days/week in-person) If you want to More ❯

AI Startup – Up to 85k 🚀🧠 💰 Salary: £50,000 - £85,000 + meaningful equity 🏙️ Location : London, flexible working arrangements, ideally 1/2 days in office 💻 Tech Stack : Python, Flask, FastAPI, React, TypeScript, GCP (Backend Leaning) Our y-combinator backend client are building an elite engineering team within the AI space. The platform is being used across the globe and is More ❯

AI Startup – Up to 85k 🚀🧠 💰 Salary: £60,000 - £85,000 + meaningful equity 🏙️ Location : London, flexible working arrangements, ideally 1/2 days in office 💻 Tech Stack : Python, Flask, FastAPI, React, TypeScript, GCP (Backend Leaning) Our y-combinator backend client are building an elite engineering team within the AI space. The platform is being used across the globe and is More ❯

and scalability decisions Building robust APIs and backend systems that power real-world AI products Helping shape the engineering culture and technical direction of the company 🛠️ Tech Stack Python | FastAPI | AWS | LangChain | TypeScript | Next.js (You don’t need to know every tool — they’re looking for curious engineers who love to learn fast.) 💰 Compensation & Equity There are no preset limits More ❯

and scalability decisions Building robust APIs and backend systems that power real-world AI products Helping shape the engineering culture and technical direction of the company 🛠️ Tech Stack Python | FastAPI | AWS | LangChain | TypeScript | Next.js (You don’t need to know every tool — they’re looking for curious engineers who love to learn fast.) 💰 Compensation & Equity There are no preset limits More ❯

build RAG pipelines, and integrate AI components into distributed systems that enable real-world, production-scale AI deployment . 🔧 What You’ll Do Architect and develop backend systems (Python, FastAPI, Flask, NodeJS) Design and implement RAG pipelines (LangChain, Qdrant, embeddings) Build ETL & CI/CD workflows (Airflow, dbt, MLFlow) Integrate AI/LLM components into backend services Ensure reliability, scalability More ❯

build RAG pipelines, and integrate AI components into distributed systems that enable real-world, production-scale AI deployment . 🔧 What You’ll Do Architect and develop backend systems (Python, FastAPI, Flask, NodeJS) Design and implement RAG pipelines (LangChain, Qdrant, embeddings) Build ETL & CI/CD workflows (Airflow, dbt, MLFlow) Integrate AI/LLM components into backend services Ensure reliability, scalability More ❯

role in evolving our client's core platform developing APIs, data workflows, and system integrations that power bespoke digital tools for major clients. Youll work hands-on with Python, FastAPI, SQL, and orchestration tools, taking automation-generated code and making it production-ready. Youll also be a champion of AI-assisted development, helping to embed LLM-based workflows into day … to-day engineering processes. Key Responsibilities Build and enhance backend features and integrations (Python, FastAPI, gRPC, SQL). Extend auto-generated pipelines and front-end automation outputs. Develop connectors for APIs, files, and external systems. Integrate LLM-based capabilities with strong testing and monitoring practices. Lead best practices for AI-assisted coding tools Collaborate closely with cross-functional teams including More ❯

in evolving our client's core platform — developing APIs, data workflows, and system integrations that power bespoke digital tools for major clients. You’ll work hands-on with Python, FastAPI, SQL, and orchestration tools, taking automation-generated code and making it production-ready. You’ll also be a champion of AI-assisted development, helping to embed LLM-based workflows into … day-to-day engineering processes. Key Responsibilities Build and enhance backend features and integrations (Python, FastAPI, gRPC, SQL). Extend auto-generated pipelines and front-end automation outputs. Develop connectors for APIs, files, and external systems. Integrate LLM-based capabilities with strong testing and monitoring practices. Lead best practices for AI-assisted coding tools Collaborate closely with cross-functional teams More ❯

with less than 10 heads, and they're now looking for a founding-level engineer to join the core London team. Tech stack: Frontend : React, Next.js, TypeScript Backend : Python, FastAPI Happy for candidates to lean towards to backend or the frontend Why this role stands out: Stealth-stage, high-impact : You’ll work on tech that’s pre-launch but More ❯

when to invest in solid foundations. Champion best practices in testing, reliability, and security. What You’ll Need Strong engineering fundamentals and experience shipping reliable systems. Proficiency in Python (FastAPI), SQLAlchemy, Pydantic, PostgreSQL, GCP Experience building AI products and working closely with users. Fosters a start up mindset & comfortable working in a fast paced environment If you love solving complex More ❯

directly with the CTO and founding team, you’ll design backend architecture, build data pipelines, and integrate AI/LLM components into production systems. Role Breakdown: 50% Backend Engineering: FastAPI, Flask, Node.js, CI/CD 30% Data Engineering: ETL, DBT, Airflow 20% AI/LLM Integration: LangChain, RAG pipelines, orchestration Key Responsibilities: Design and build backend services to support AI More ❯

Working directly with the CTO and founding team, youll design backend architecture, build data pipelines, and integrate AI/LLM components into production systems. Role Breakdown: 50% Backend Engineering: FastAPI, Flask, Node.js, CI/CD 30% Data Engineering: ETL, DBT, Airflow 20% AI/LLM Integration: LangChain, RAG pipelines, orchestration Key Responsibilities: Design and build backend services to support AI More ❯

and problem-solvers — all passionate about writing clean, scalable code and continuously improving their platform. ⭐ What You'll Do Design, build, and maintain backend services using Python (Django/FastAPI) Contribute to architecture and technical design discussions Write clean, maintainable, and well-tested code Work closely with Product and Frontend teams to deliver new features Help improve scalability, performance, and … practices and contribute to a culture of engineering excellence Work on meaningful challenges that have a direct impact on customers 👩 💻 What You'll Need Strong experience with Django or FastAPI Solid understanding of RESTful APIs and database design (SQL/PostgreSQL) Experience with testing frameworks and version control (Git) Familiarity with cloud environments (AWS/GCP/Azure) A collaborative … love to hear from you. 📩 Apply now to learn more about the company and this opportunity! (Python Engineer, Python Developer, Backend Developer, Software Developer, Software Engineer, Django Developer, Django, FastAPI, Flask, AWS, SaaS, REST API, Cloud, CI/CD, Start-up, London, Hybrid More ❯

and problem-solvers — all passionate about writing clean, scalable code and continuously improving their platform. ⭐ What You'll Do Design, build, and maintain backend services using Python (Django/FastAPI) Contribute to architecture and technical design discussions Write clean, maintainable, and well-tested code Work closely with Product and Frontend teams to deliver new features Help improve scalability, performance, and … practices and contribute to a culture of engineering excellence Work on meaningful challenges that have a direct impact on customers 👩 💻 What You'll Need Strong experience with Django or FastAPI Solid understanding of RESTful APIs and database design (SQL/PostgreSQL) Experience with testing frameworks and version control (Git) Familiarity with cloud environments (AWS/GCP/Azure) A collaborative … love to hear from you. 📩 Apply now to learn more about the company and this opportunity! (Python Engineer, Python Developer, Backend Developer, Software Developer, Software Engineer, Django Developer, Django, FastAPI, Flask, AWS, SaaS, REST API, Cloud, CI/CD, Start-up, London, Hybrid More ❯

a fast-paced, high-autonomy role where your work directly impacts the future of the product. Key Responsibilities Design and implement new backend endpoints and services using Python and FastAPI building on the existing codebase Build and maintain scalable REST APIs, integrating PostgreSQL for robust data management Lead the development of AI/LLM-powered features, leveraging tools like Langchain … deployments, working in a team of 4. Qualifications 3 Years of professional programming experience. Strong proficiency in Python, with a proven track record of backend development Deep experience with FastAPI, RESTful API design, and PostgreSQL Hands-on experience developing scalable systems and backend architectures Familiarity with Langchain, AI, or LLM tooling is a strong plus Proficiency with Docker, GitHub, and More ❯

Sells: Work on cutting-edge AI systems that power healthcare innovation at scale. Full remote flexibility across the UK, total ownership of greenfield projects, modern tech stack (Python/FastAPI/Cloud), and a culture that rewards curiosity, autonomy, and clean engineering. An AI HealthTech company is expanding its high-calibre engineering team and looking for Software Engineers who thrive … engineering role where you'll be designing, building, and scaling complex systems that solve real problems in healthcare. Role Design and build production-grade backend systems using Python and FastAPI Develop distributed, high-performance services and APIs for AI-driven platforms Contribute to architecture decisions, scalability planning, and system optimisation Implement best practices in testing, CI/CD, and performance … end-to-end solutions Drive continuous improvement and innovation across the engineering organisation Skills 5+ years of experience as a Software Engineer building modern backend systems Strong Python skills (FastAPI preferred; Flask or Django also considered) Knowledge of system design, data modelling, and distributed architecture Familiarity with cloud technologies (AWS, Azure, or GCP) and containerisation Understanding of software engineering best More ❯