Principal Software Engineer at Simple Machines is a hybrid, full-time position based in London, United Kingdom. Simple Machines is a boutique technology firm delivering data, AI, and software solutions to enterprises, governments, and technology companies worldwide. In this hands-on role you will design and deliver complex, scalable full-stack systems across backend services, APIs, frontend components, data pipelines, and cloud infrastructure. You will own the design of APIs and supporting infrastructure, document technical designs for internal teams and clients, and drive end-to-end delivery from development through deployment and operation. You will collaborate with clients and delivery teams to translate business requirements into robust technical solutions, operating in an Agile, iterative environment. You will join a high-performing engineering team working on a large-scale machine learning platform for a global telecommunications client, with autonomy and shared ownership. Core qualifications include strong JVM-based development (Kotlin preferred, Java welcome), experience designing data-driven APIs and large-scale web services, solid SQL and performance-aware queries, and automated testing (TDD/BDD preferred). You should have frontend and full-stack experience (React, TypeScript, Redux, Tailwind), and cloud/infrastructure experience (AWS, GCP, Azure, Terraform, CloudFormation) with containerization (Docker, ECS, Kubernetes). Nice-to-have skills include exposure to Scala or functional programming concepts, experience with asynchronous and highly concurrent backend fra

Principal Software Engineer at Simple Machines is a hybrid, full-time position based in London, United Kingdom. Simple Machines is a boutique technology firm delivering data, AI, and software solutions to enterprises, governments, and technology companies worldwide. In this hands-on role you will design and deliver complex, scalable full-stack systems across backend services, APIs, frontend components, data pipelines, and cloud infrastructure. You will own the design of APIs and supporting infrastructure, document technical designs for internal teams and clients, and drive end-to-end delivery from development through deployment and operation. You will collaborate with clients and delivery teams to translate business requirements into robust technical solutions, operating in an Agile, iterative environment. You will join a high-performing engineering team working on a large-scale machine learning platform for a global telecommunications client, with autonomy and shared ownership. Core qualifications include strong JVM-based development (Kotlin preferred, Java welcome), experience designing data-driven APIs and large-scale web services, solid SQL and performance-aware queries, and automated testing (TDD/BDD preferred). You should have frontend and full-stack experience (React, TypeScript, Redux, Tailwind), and cloud/infrastructure experience (AWS, GCP, Azure, Terraform, CloudFormation) with containerization (Docker, ECS, Kubernetes). Nice-to-have skills include exposure to Scala or functional programming concepts, experience with asynchronous and highly concurrent backend fra