1 to 25 of 97 Open Source Jobs in London

Senior Software Engineer - Backend

Hiring Organisation
Zettafleet
Location
South London, UK
Employment Type
Full-time
like to acknowledge that almost no candidate checks every box – and that is perfectly fine. If you are passionate about solving complex challenges and open to learning new technologies, we would love to hear from you. How we work: We are a small, early-stage team with big ambitions. … motivated by impact tend to thrive. Nice to have: Machine Learning: Experience in generative models, LLMs, multi-modal models and Deep Learning more generally. Open-source: Contributions to and experience in open-source projects. Startup experience: Experience in an early-stage startup environment. Why join ...

Senior Software Engineer, C++

Hiring Organisation
Ripple
Location
London, UK
Employment Type
Full-time
full software development lifecycle, including architecture, technical design, C++ development, bug fixing, as well as functional and performance validations. Be part of the open-source XRP ledger community, setting high standards for coding, testing, and deployment. Actively participate in code reviews to maintain the high quality … Ability to learn new technologies and languages quickly. Ability to independently solve highly complex problems with creative solutions. Nice to have: Experience in developing open-source software and contributing to collaborative blockchain communities. WHO WE ARE: Do Your Best Work The opportunity to build in a fast-paced ...

Staff Software Engineer, C++

Hiring Organisation
Ripple
Location
London, England, United Kingdom
full software development lifecycle, including architecture, technical design, C++ development, bug fixing, as well as functional and performance validations. Be part of the open-source XRP ledger community, setting high standards for coding, testing, and deployment. Actively participate in code reviews to maintain the high quality … Ability to learn new technologies and languages quickly. Ability to independently solve highly complex problems with creative solutions. Nice to have: Experience in developing open-source software and contributing to collaborative blockchain communities. Other common names for this role: C++ Developer, Staff C++ Engineer ...

Backend Engineer (Distributed Systems Engineer)

Hiring Organisation
TechChain Talent
Location
City of London, London, United Kingdom
that scale across thousands of nodes • Performance-critical modules for consensus, networking, and data pipelines • Internal tooling for observability, testing, and simulation • Contributions to open-source infra and protocol-level primitives What You Bring • 5+ years of backend engineering experience in systems-level environments • Deep knowledge of distributed … cloud-native infra • Familiarity with blockchain, cryptographic protocols, or decentralized coordination Bonus Points • Experience in zero-knowledge systems, MPC, or verifiable computation • Contributions to open-source infra projects • Prior work in Layer 1 or Layer 2 blockchain development Why Join • Stealth-stage impact with protocol-grade ownership • Competitive ...

Java Engineer

Hiring Organisation
Profile 29
Location
South East London, London, United Kingdom
Employment Type
Permanent, Work From Home
Salary
£60,000
case-management or service-orchestration platforms Understanding of agentic AI capabilities and how they can complement workflow automation Experience mentoring developers or contributing to open-source Camunda extensions Already holding UK security clearance (SC, DV, eDV) What They Offer A company option scheme gives their employees a stake ...

AI Prompt Engineering Consultant

Hiring Organisation
Staffworx
Location
London, England, United Kingdom
model safety, bias mitigation, evaluation frameworks and governance. Background in Computer Science, AI/ML, Engineering, or related fields. Experience deploying or fine-tuning open-source LLMs. TECH STACK LLMs: GPT-4/5, Claude 3.x, Gemini 2.x, Mistral Large, LLaMA 3, Cohere Command R+, DeepSeek Frameworks: LangChain ...

AI Automation Engineer

Hiring Organisation
McCabe & Barton
Location
Central London, London, United Kingdom
Employment Type
Permanent
practices for production deployment. Generative AI & LLM Integration - Proficient in working with Large Language Models including OpenAI GPT models, Anthropic Claude, Azure OpenAI, and open-source alternatives (Llama, Mistral). Experience with prompt engineering, fine-tuning, RAG (Retrieval Augmented Generation) architectures, vector databases (Pinecone, ChromaDB, FAISS), embeddings ...

AI Automation Engineer

Hiring Organisation
McCabe & Barton
Location
City of London, London, United Kingdom
Employment Type
Contract
Contract Rate
Up to £700 per day
practices for production deployment. Generative AI & LLM Integration - Proficient in working with Large Language Models including OpenAI GPT models, Anthropic Claude, Azure OpenAI, and open-source alternatives (Llama, Mistral). Experience with prompt engineering, fine-tuning, RAG (Retrieval Augmented Generation) architectures, vector databases (Pinecone, ChromaDB, FAISS), embeddings ...

Senior Full Stack Engineer (Golang/Typescript/Kubernetes)

Hiring Organisation
Safe Intelligence
Location
City of London, London, United Kingdom
experience with Python, modern development techniques, and design patterns. Experience in data science tools and ML tools (e.g., NumPy, pandas, scikit-learn, PyTorch) and open-source contributions (especially Python-based) would be a bonus. Familiarity with CUDA, GPU-based computations, end-to-end neural network training, MLOps ...

Senior Software Engineer

Hiring Organisation
Expedia Group
Location
London, UK
Employment Type
Full-time
success. Why Join Us? To shape the future of travel, people must come first. Guided by our Values and Leadership Agreements, we foster an open culture where everyone belongs, differences are celebrated and know that when one of us wins, we all win. We provide a full benefits package … offices), and career development resources, all to fuel our employees' passion for travel and ensure a rewarding career journey. We're building a more open world. Join us. Expedia Group Advertising is redefining how travel brands connect with global audiences. Our Publishing Team owns the end-to-end delivery ...

Data Science Manager

Hiring Organisation
24 Seven Talent
Location
London, UK
Employment Type
Full-time
Data Science, Statistics, Computer Science, or related field. 5+ years of experience in data science and machine learning. Strong proficiency in Python, SQL, and open-source tools. Experience with Generative AI frameworks and production-ready model deployment. Familiarity with cloud platforms (e.g., BigQuery, Azure, GCS) and containerization (Docker ...

Senior Go Developer

Hiring Organisation
Fruition Group
Location
London, United Kingdom
Employment Type
Contract, Work From Home
focused approach, ideally within fast-paced tech organisations (start-ups or scale-ups) Knowledge of Kafka, Cassandra, gRPC, and microservices is a strong advantage Open-source contributions are beneficial If you're a Senior Go Developer looking for a challenging 6-month contract with a forward-thinking tech ...

Senior Staff Engineer (Machine Learning) - 45391

Hiring Organisation
Turing
Location
London, UK
Employment Type
Full-time
Science, Engineering, or related field (PhD preferred). Nice to Have: Experience building Agentic applications Experience training or fine-tuning foundation models. Contributions to open-source ML or LLM frameworks. Understanding of Responsible AI, bias mitigation, and model interpretability. Perks of Freelancing With Turing: Work in a fully ...

Lead Software Engineer (Scala & Spark)

Hiring Organisation
Aker Systems Limited
Location
Central London, London, United Kingdom
Employment Type
Permanent
years. As a Software Engineer, you will help lead the development of backend services for a government client leveraging the latest commercial and open-source technologies. This involves designing, developing, documenting and deploying backend services with a focus on high availability, low latency and scalability. Design, develop, document … clean code, documentation, defensive programming, automated testing and code reviews Working in Agile development and/or DevOps teams Using GitHub/GitLab for source control Test Driven Development with appropriate tools and frameworks Experience in Big Data technologies Experience in Public Cloud services, such as AWS Aker Systems ...

Senior Go Developer

Hiring Organisation
Fruition Group
Location
London, United Kingdom
Employment Type
Contract
take ownership across the full development lifecycle, from system design and implementation to optimisation and release. You'll be working in an open, fast-moving environment where ideas get tested quickly and good engineering practices are taken seriously. If you like seeing your work go live within days … technology-driven organisations or start-ups Experience with Kafka, Cassandra, gRPC, and microservices architecture will also be beneficial, as well as experience contributing to open-source projects If you're a Senior Go Developer looking for a fast-paced, collaborative contract role where your work will ship quickly ...

AWS Cloud Engineer

Hiring Organisation
Harnham - Data & Analytics Recruitment
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£70,000 - £80,000 per annum
ability to work independently and collaboratively Highly desirable AWS certifications (e.g., DevOps Engineer, Solutions Architect) Experience with AWS generative AI services (Bedrock, SageMaker) Open-source contributions demonstrating engineering best practices Benefits Work on cutting-edge generative AI projects Join a talented, innovative team Competitive salary and benefits package ...

Lead Software Engineer

Hiring Organisation
Durlston Partners
Location
London, UK
Employment Type
Full-time
Proven use of AI coding assistants (GitHub Copilot, Claude Code, Cursor) to accelerate development Evidence of applying technology beyond your day job – side projects, open source contributions, or building tools that solve real problems Someone who naturally gravitates toward using technology to make things better Nice to Have ...

Machine Learning Engineer

Hiring Organisation
Higher - AI recruitment
Location
City of London, London, United Kingdom
software engineering skills with a focus velocity Excellent communication skills and the ability to flourish in a team Located in London/Paris and open to working in office Tech Stack: Python FastAPI Python, Typescript, or React Open source LLMs Building for production Benefits Currently Offered (likely ...

Platform Engineer

Hiring Organisation
heata
Location
London, UK
Employment Type
Full-time
whilst supporting households with lower energy bills. Working in partnership with SecureLinx and SUSE, we've established a robust technical, secure foundation using modern open-source, cloud-native technologies. Now we're ready to scale - expanding capability, automation and performance as we grow our client base, which comprises …/Contract also considered Company Based in Godalming (GU7 1EY) adjacent to Station; Regular trains from Waterloo Additional hot desk space available in Waterloo Open to hybrid or remote working depending on the candidate ...

Junior C++ Engineer

Hiring Organisation
Harrington Starr
Location
City of London, London, United Kingdom
distributed systems, concurrency, or network programming Experience working with low-latency or real-time systems Familiarity with trading platforms, data pipelines, or simulation tools Open-source contributions or personal technical projects that demonstrate initiative Contact Ciara Clarke at Harrington Starr for a confidential discussion. ...

Lead Ai Engineer

Hiring Organisation
Sanderson
Location
City of London, London, United Kingdom
Design, develop, and fine-tune Large Language Models (LLMs) and Generative AI solutions using frameworks like OpenAI, Anthropic Claude, Gemini, or open-source models. Build and optimise RAG pipelines , vector databases, and prompt engineering strategies for enhanced AI responses. Develop AI-powered applications integrating LLMs with APIs, agents ...

C# .Net Developer

Hiring Organisation
Damia Group Ltd
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£500 - £650/day
team Solid C# .Net experience Fine-tune Large Language Models (LLMs) and other generative architectures. Optimise pre-trained models (OpenAI, Anthropic, or open-source LLMs) for business use cases using prompt engineering and reinforcement learning. Experiment with model configurations to balance performance, cost, and scalability. Build robust data ...

Software Engineer

Hiring Organisation
Venture 2
Location
South London, UK
Employment Type
Full-time
style. Nice to Have · Experience with model serving, quantisation, or distributed inference. · Exposure to containerisation and cloud environments (AWS/DO). · Projects or open-source contributions demonstrating capability and initiative. · Experience in data engineering, cybersecurity, prediction systems or financial systems. · Ability to own the delivery pipeline from ...

Research Engineer

Hiring Organisation
Vertex Search
Location
City of London, London, United Kingdom
Experience building pipelines for scientific or healthcare data Knowledge of cluster compute, distributed training and GPUs Understanding of healthcare data or regulated environments Open-source contributions Cloud experience (AWS/GCP/Azure) Compensation & Benefits Excellent base salary Generous equity allocation from day one Comprehensive health & wellness package ...

Lead Software Engineer (Founding Team)

Hiring Organisation
BroadbandUK
Location
East London, London, United Kingdom
Employment Type
Permanent
startup environments, enjoy solving real problems, and learn quickly. Proven impact: Youve built and scaled products, led projects that made a difference, contributed to open-source, or delivered results that truly moved the needle. Why youll love it here Impact from day one: Your work goes live quickly ...