Solution / Technical Architect – Python Expert (FastAPI, Flask, Microservices), Inside IR35 Onsite / Hybrid working - 6 month contract Our client is seeking an experienced Solution Architect with a strong background in Python and modern microservices to help shape the future of their backend systems. This role is ideal for someone who enjoys driving architecture decisions, leading technical direction, and delivering scalable, cloud-native platforms. You’ll be joining a fast-paced environment where your work will have a direct impact on the design and delivery of mission-critical platforms. The successful candidate will combine strategic vision with hands-on technical expertise, guiding engineering teams while influencing long-term architecture. Role Overview Architect scalable, modular backend solutions using Python (FastAPI, Flask) and microservices. Lead technical design across APIs, data pipelines, cloud infrastructure, and backend orchestration. Drive architecture reviews, documentation, and system governance. Work closely with DevOps and engineering teams to build cloud-native systems on AWS with CI/CD. Mentor engineers and foster best practices across the development lifecycle. Translate business requirements into practical, high-quality technical solutions. Key Requirements 8 years backend engineering experience, with 3 years in a solution architect/lead role. Advanced knowledge of Python, particularly FastAPI or Flask. Strong experience in microservices, RESTful APIs, and distributed systems. Hands-on expertise with data pipelines, background jobs, message queues, and integrations. AWS experience (ECS, EC2, Lambda, VPC, S3) and CI/CD (GitLab CI or similar). Proficiency with Docker and containerisation workflows. Excellent communication skills, able to explain technical concepts clearly. Nice to Have Exposure to frontend integration (React). Database experience with MongoDB, PostgreSQL, or similar. Experience in compliance-sensitive sectors (finance, insurance, legal tech). Open-source contributions or community involvement. All our roles are UK based. When submitting your application to Colossus, please ensure the following Your CV has your address and postcode. You also have your correct phone number and email address so we can contact you asap regarding your application. For confidentiality purposes, please remove any reference contact phone number's and email address details from your CV.