1 to 25 of 117 Open Source Jobs in the City of London

Min 4 days per week in office) Maze is partnering with a stealth-mode startup that's rebuilding core banking from the ground up. Theyre creating the worlds first open-source, AI-native Thin Ledgerset to replace legacy infrastructure at Tier 1 banks. We're looking for a Principal Platform Engineer to drive the infrastructure behind mission-critical … incident response AI-curious or AI-native: excited to build agent-powered ops Someone who is currently hands on (not someone primarily focused on strategy & people management) Passion for open-source, clean architecture Software Development experience (Bonus points for Go(Golang)) Bonus: background in financial systems, core banking, or regulated infra Why join: Huge ownership: build core infra … Work with a high-caliber team, fast-paced and product-minded founders who have worked in some of the most recognised tech businesses in the world. Help define an open-source platform from day one. Clear path to tech unicorn status with fruitful equity included. Recently raised 8 figures in funding. If your skillset matches, apply within. Please More ❯

days per week in office) Maze is partnering with a stealth-mode startup that's rebuilding core banking from the ground up. They’re creating the world’s first open-source, AI-native "Thin Ledger"—set to replace legacy infrastructure at Tier 1 banks. We're looking for a Principal Platform Engineer to drive the infrastructure behind mission … incident response AI-curious or AI-native: excited to build agent-powered ops Someone who is currently hands on (not someone primarily focused on strategy & people management) Passion for open-source, clean architecture Software Development experience (Bonus points for Go(Golang)) Bonus: background in financial systems, core banking, or regulated infra Why join: Huge ownership: build core infra … Work with a high-caliber team, fast-paced and product-minded founders who have worked in some of the most recognised tech businesses in the world. Help define an open-source platform from day one. Clear path to tech unicorn status with fruitful equity included. Recently raised 8 figures in funding. If your skillset matches, apply within. Please More ❯

days per week in office) Maze is partnering with a stealth-mode startup that's rebuilding core banking from the ground up. They’re creating the world’s first open-source, AI-native "Thin Ledger"—set to replace legacy infrastructure at Tier 1 banks. We're looking for a Principal Platform Engineer to drive the infrastructure behind mission … incident response AI-curious or AI-native: excited to build agent-powered ops Someone who is currently hands on (not someone primarily focused on strategy & people management) Passion for open-source, clean architecture Software Development experience (Bonus points for Go(Golang)) Bonus: background in financial systems, core banking, or regulated infra Why join: Huge ownership: build core infra … Work with a high-caliber team, fast-paced and product-minded founders who have worked in some of the most recognised tech businesses in the world. Help define an open-source platform from day one. Clear path to tech unicorn status with fruitful equity included. Recently raised 8 figures in funding. If your skillset matches, apply within. Please More ❯

About WSO2 Founded in 2005, WSO2 is the largest independent software vendor providing open-source API management, integration, and identity and access management (IAM) to thousands of enterprises in over 90 countries. WSO2's products and platformsincluding our next-gen internal developer platform, Choreoempower organizations to leverage the full potential of artificial intelligence and APIs for securely delivering … the next generation of AI-enabled digital services and applications. Our open-source, AI-driven, API-first approach frees developers and architects from vendor lock-in and enables rapid digital product creation. Recognized as leaders by industry analysts, WSO2 has more than 800 employees worldwide with offices in Australia, Brazil, Germany, India, Sri Lanka, the UAE, the UK … developers and customers, turning them into advocates, references, and sources of powerful case studies and testimonials. 3. Market Intelligence and Product Influence Own market expertise: Serve as the central source of intelligence on the technical landscape, competitor strategies, market trends, and pricing dynamics. Drive pricing and packaging strategy: Conduct market analysis and collaborate with Product and Finance to define More ❯

About WSO2 Founded in 2005, WSO2 is the largest independent software vendor providing open-source API management, integration, and identity and access management (IAM) to thousands of enterprises in over 90 countries. WSO2's products and platforms—including our next-gen internal developer platform, Choreo—empower organizations to leverage the full potential of artificial intelligence and APIs for … securely delivering the next generation of AI-enabled digital services and applications. Our open-source, AI-driven, API-first approach frees developers and architects from vendor lock-in and enables rapid digital product creation. Recognized as leaders by industry analysts, WSO2 has more than 800 employees worldwide with offices in Australia, Brazil, Germany, India, Sri Lanka, the UAE … developers and customers, turning them into advocates, references, and sources of powerful case studies and testimonials. 3. Market Intelligence and Product Influence Own market expertise: Serve as the central source of intelligence on the technical landscape, competitor strategies, market trends, and pricing dynamics. Drive pricing and packaging strategy: Conduct market analysis and collaborate with Product and Finance to define More ❯

Provide best Customer experience in terms of responsiveness, resolution time, tone, and knowledge Support the customer throughout their entire lifecycle Provide expert-level technical support for customers using our Open Source Ledger and other backend modules. Troubleshoot complex issues, investigating and diagnosing problems quickly, and escalating them to the development team when necessary. Create and maintain detailed documentation … product teams to deliver seamless support and relay feedback for continuous improvement. Ability to prioritize and manage multiple tickets/issues Fluent in English Nice to have : Familiarity with open-source ecosystems, APIs, webhooks, or BE tools Basic understanding of financial services infrastructure (ledgers, reconciliation, transactions) Benefits We offer a competitive package including equity for employees. We organize … regular off-sites with the team in Europe and soon in the US! About FORMANCE : Formance is building the next-generation financial infrastructure - open-source, developer-first, and built to power the most ambitious fintech products of tomorrow. Formance is global native and serving enterprise companies around the globe, around the clock, to build and scale their financial More ❯

Provide best Customer experience in terms of responsiveness, resolution time, tone, and knowledge Support the customer throughout their entire lifecycle Provide expert-level technical support for customers using our Open Source Ledger and other backend modules. Troubleshoot complex issues, investigating and diagnosing problems quickly, and escalating them to the development team when necessary. Create and maintain detailed documentation … product teams to deliver seamless support and relay feedback for continuous improvement. Ability to prioritize and manage multiple tickets/issues Fluent in English Nice to have : Familiarity with open-source ecosystems, APIs, webhooks, or BE tools Basic understanding of financial services infrastructure (ledgers, reconciliation, transactions) Benefits We offer a competitive package including equity for employees. We organize … regular off-sites with the team in Europe and soon in the US! About FORMANCE: Formance is building the next-generation financial infrastructure - open-source, developer-first, and built to power the most ambitious fintech products of tomorrow. Formance is global native and serving enterprise companies around the globe, around the clock, to build and scale their financial More ❯

enjoy solving complex challenges, we would love to hear from you. Nice to have: Publications: At top-tier ML/CV/NLP conferences (NeurIPS, ICML, ICLR, CVPR, ICCV) Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

enjoy solving complex challenges, we would love to hear from you. Nice to have: Publications: At top-tier ML/CV/NLP conferences (NeurIPS, ICML, ICLR, CVPR, ICCV) Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

enjoy solving complex challenges, we would love to hear from you. Nice to have: Publications: At top-tier ML/CV/NLP conferences (NeurIPS, ICML, ICLR, CVPR, ICCV) Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

enjoy solving complex challenges, we would love to hear from you. Nice to have: Publications: At top-tier ML/CV/NLP conferences (NeurIPS, ICML, ICLR, CVPR, ICCV) Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

enjoy solving complex challenges, we would love to hear from you. Nice to have: Publications: At top-tier ML/CV/NLP conferences (NeurIPS, ICML, ICLR, CVPR, ICCV) Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

enjoy solving complex challenges, we would love to hear from you. Nice to have: Publications: At top-tier ML/CV/NLP conferences (NeurIPS, ICML, ICLR, CVPR, ICCV) Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

tasks. Collaboration and communication: Excellent interpersonal and communication skills, with technical and non-technical stakeholders. Nice to have: Visual design: Background in graphic design and/or visual arts. Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

tasks. Collaboration and communication: Excellent interpersonal and communication skills, with technical and non-technical stakeholders. Nice to have: Visual design: Background in graphic design and/or visual arts. Open-source: Contributions to and experience in open-source projects. Startup experience: Experience with a startup work environment and wider ecosystem. Why join us? Work in an More ❯

Founded in 2023, the company has already secured significant early-stage funding, including a $10m Seed round in 2024. The founding team is composed of ex-Palantir and ex-Open AI leaders. They combine deep sector knowledge with cutting-edge design and software engineering expertise to deliver state-of-the-art SaaS capabilities leveraging NLP, Generative AI, and reinforcement … or equivalent experience 5+ years of experience working with cross-functional software development teams Experience shipping and iterating on production-grade software components professionally and/or in the open-source community Ability to write robust, well tested, and well-designed code that frequently gets deployed to users Strong understanding of product development and navigating large codebases Located … in London/Paris and open to working in office Tech Stack: Python FastAPI Typescript + React Open source LLMs On premise deployments Benefits Currently Offered (likely to improve as company grows): 100% coverage for travel expenses Childcare support Min. 3 months fully paid parental leave 25 days holiday + bonus days for company closure Subsidised lunches More ❯

Founded in 2023, the company has already secured significant early-stage funding, including a $10m Seed round in 2024. The founding team is composed of ex-Palantir and ex-Open AI leaders. They combine deep sector knowledge with cutting-edge design and software engineering expertise to deliver state-of-the-art SaaS capabilities leveraging NLP, Generative AI, and reinforcement … or equivalent experience 5+ years of experience working with cross-functional software development teams Experience shipping and iterating on production-grade software components professionally and/or in the open-source community Ability to write robust, well tested, and well-designed code that frequently gets deployed to users Strong understanding of product development and navigating large codebases Located … in London/Paris and open to working in office Tech Stack: Python FastAPI Typescript + React Open source LLMs On premise deployments Benefits Currently Offered (likely to improve as company grows): 100% coverage for travel expenses Childcare support Min. 3 months fully paid parental leave 25 days holiday + bonus days for company closure Subsidised lunches More ❯

Energy Domain is a must. Under 7 years of experience only. Permanent. Key Responsibilities Design, develop, and maintain data ingestion pipelines using open-source frameworks and tools Build and optimise ETL/ELT processes to handle small to large-scale data processing requirements Develop data models and schemas that support analytics, business intelligence and product needs Monitor, troubleshoot … in data processing libraries (pandas, NumPy, Apache Spark) Hands-on experience building and maintaining data ingestion pipelines Proven track record of optimising queries, code, and system performance Experience with open-source data processing frameworks (Apache Spark, Apache Kafka, Apache Airflow) Knowledge of distributed computing concepts and big data technologies Experience with version control systems (Git) and CI/ More ❯

Energy Domain is a must. Under 7 years of experience only. Permanent. Key Responsibilities Design, develop, and maintain data ingestion pipelines using open-source frameworks and tools Build and optimise ETL/ELT processes to handle small to large-scale data processing requirements Develop data models and schemas that support analytics, business intelligence and product needs Monitor, troubleshoot … in data processing libraries (pandas, NumPy, Apache Spark) Hands-on experience building and maintaining data ingestion pipelines Proven track record of optimising queries, code, and system performance Experience with open-source data processing frameworks (Apache Spark, Apache Kafka, Apache Airflow) Knowledge of distributed computing concepts and big data technologies Experience with version control systems (Git) and CI/ More ❯

the core C++ codec integration layers. Integration work for other compression solutions, such as VC6 and point cloud compression, into different video editing and creation applications. Engaging with the open-source community to contribute changes upstream to video player open-source projects and assist with their integration of LCEVC. Development activity planning, including sprint planning and More ❯

the core C++ codec integration layers. Integration work for other compression solutions, such as VC6 and point cloud compression, into different video editing and creation applications. Engaging with the open-source community to contribute changes upstream to video player open-source projects and assist with their integration of LCEVC. Development activity planning, including sprint planning and More ❯

Go Developer Location: London Bridge Hybrid: 1x every fortnight We are working with a small, technical team based in London Bridge to build innovative solutions, working with cutting-edge, open-source platform frameworks. As a Senior Go Developer, you will work on complex distributed systems, shaping modern development, contributing to product design and working closely with customers to … improving engineering efficiency Experience in working in Agile environments London Bridge, Hybrid (1 day in office every 2 weeks) Salary (£90-120k DOE) Culture: Forward thinking, engineering-led, open-source focused. Apply now for more information. More ❯

to £200k + Equity | London Maze is partnering with a stealth-mode startup that's rebuilding core banking from the ground up. They’re creating the world’s first open-source, AI-native "Thin Ledger" —set to replace legacy infrastructure at Tier 1 banks. We're looking for a Senior Engineer specialising in Go to contribute to v1 … distributed, multi-region infra with five-nines reliability Contribute to backend, DevOps, and CI/CD decision-making Embed AI into engineering workflows & ops Self-motivated, problem-solving mindset; open to non-traditional backgrounds. You should have: Expert backend skill ideally in Golang, or Rust, Zig or C. Deep expereince building distributed systems from scratch. Experience in greenfield projects … Work with a high-caliber team, fast-paced and product-minded founders who have worked in some of the most recognised tech businesses in the world. Help define an open-source platform from day one. Clear path to tech unicorn status with fruitful equity included. Recently raised 8 figures in funding. Apply within if your skillset matches! Please More ❯

to £200k + Equity | London Maze is partnering with a stealth-mode startup that's rebuilding core banking from the ground up. They’re creating the world’s first open-source, AI-native "Thin Ledger" —set to replace legacy infrastructure at Tier 1 banks. We're looking for a Senior Engineer specialising in Go to contribute to v1 … distributed, multi-region infra with five-nines reliability Contribute to backend, DevOps, and CI/CD decision-making Embed AI into engineering workflows & ops Self-motivated, problem-solving mindset; open to non-traditional backgrounds. You should have: Expert backend skill ideally in Golang, or Rust, Zig or C. Deep expereince building distributed systems from scratch. Experience in greenfield projects … Work with a high-caliber team, fast-paced and product-minded founders who have worked in some of the most recognised tech businesses in the world. Help define an open-source platform from day one. Clear path to tech unicorn status with fruitful equity included. Recently raised 8 figures in funding. Apply within if your skillset matches! Please More ❯

to maximise efficiency Automate model experimentation, tuning and retraining in partnership with research teams Work with infrastructure specialists to optimise workflows and reduce compute costs Assess and integrate emerging open-source tools to enhance ML development and deployment Skills and Experience 5+ years’ experience in machine learning with a focus on training and inference systems Strong programming expertise … Hands-on experience with GPU acceleration and distributed training (Horovod, NCCL or similar) Background in real-time, low-latency ML pipelines Familiarity with cloud and orchestration technologies Contributions to open-source ML or distributed systems projects are advantageous Why This Firm? Direct impact: your work feeds into live trading strategies, not just experiments. Buy-side edge : fewer layers More ❯