Best Open Source Companies in United Kingdom
The 84 best Open Source companies in United Kingdom in 2026, ranked by funding and momentum. Funding, investors, founders, valuation, tech stack and live signals. Top: Stability AI.
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Ranked: Best Open Source companies in United Kingdom
| # | Company | Disclosed funding | Last round | Employees | Founder | Tech stack | Web popularity | Patents & IP focus | Recent signals |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Stability AI 🦄 Developer of generative AI models for image, video, audio, and 3D 78AI top 25%Funding top 28%Moat top 28%Tech top 33% All 12 signals ▾AItop 25% Fundingtop 28% Moattop 28% Techtop 33% Patentstop 33% Talenttop 38% Markettop 40% Innovationtop 40% Growthtop 42% Globaltop 50% Productbottom 39% Newsbottom 24% AI: Classified as an AI company · Holds AI/ML patents (G06N-family CPC) Funding: Raised $206M across 2 rounds · 2 rounds over 4 yrs (0.5/yr) rank vs industry peers · Fliar Intelligence Index 78/100 | $206M | 23 mo ago | 45 | Emad Mostaque Co-Founder & CEO | Cart FunctionalitySquarespace CommerceSquarespace+29 | Top 500k | 15 patents Generative AI for 3D image, multi-angle video, and audio content synthesis | 1 launch |
| 2 | Balena Developer of an ecosystem to create, deploy, and manage fleets of connected devices 64Funding top 21%Tech top 23%Talent top 28%Moat top 31% All 10 signals ▾Fundingtop 21% Techtop 23% Talenttop 28% Moattop 31% Growthtop 35% Producttop 45% Innovationtop 46% Newstop 48% Globaltop 49% Marketbottom 37% Funding: Raised $101M across 7 rounds · 7 rounds over 13 yrs (0.5/yr) Tech: 68 technologies across 5/8 capability areas · Cloud: Cloudflare, Vercel rank vs industry peers · Fliar Intelligence Index 64/100 | $101M | 5 mo ago | 14 | Pagan Gazzard Co-Founder | WordPress Block EditorWordPress Site EditorWordPress+29 | Top 500k | — | 1 launch |
| 3 | OpenGamma Platform that provides SaaS based solutions for derivatives risk analytics | $75M | 52 mo ago | 61 61 → 51 (-16%) | Brian Zboril Founder | Apple iCloud MailGoogle WorkspaceTailwind CSS+21 | Top 10M | — | — |
| 4 | Weaveworks Enterprise Kubernetes and application management based on GitOps | $57M | 67 mo ago | 95 | — | — | — | — | — |
| 5 | Element Decentralized team messaging app for enterprises | $52M | 59 mo ago | 128 128 → 107 (-16%) | Matthew Hodgson Co-Founder | BootstrapAmazon Web ServicesAtlassian Statuspage+17 | Top 500k | — | — |
| 6 | Tyk.io Provider of an API management platform | $41M | 25 mo ago | 22 | James Hirst Co-Founder | WordPressMySQLPHP+31 | Top 5M | — | — |
| 7 | Pi-Top DIY open source laptop building kit 37Funding top 37%Talent top 38%Moat top 39%Tech top 43% All 8 signals ▾Fundingtop 37% Talenttop 38% Moattop 39% Techtop 43% Growthbottom 46% Globalbottom 39% Marketbottom 34% Newsbottom 22% Funding: Raised $40.4M across 5 rounds · 5 rounds over 11 yrs (0.5/yr) Talent: 2 named leaders on record · 2 C-suite/founder profiles curated rank vs industry peers · Fliar Intelligence Index 37/100 | $40M | 60 mo ago | 37 37 → 22 (-41%) | Jesse Lozano Co-Founder | Cart FunctionalityShopifyShop Pay+15 | Top 10M | — | — |
| 8 | Seldon Open source framework for deploying ML models | $39M | 39 mo ago | 46 46 → 89 (+93%) | Jacqueline Housley Co-Founder | WordPressMySQLPHP+24 | Top 5M | — | — |
| 9 | SurrealDB Developer of a multi-model database for AI agents and applications 40Funding top 29%Talent top 38%Moat top 39%Growth top 45% All 8 signals ▾Fundingtop 29% Talenttop 38% Moattop 39% Growthtop 45% Newstop 45% Techtop 47% Globalbottom 43% Marketbottom 27% Funding: Raised $26.0M across 3 rounds · 3 rounds over 4 yrs (0.8/yr) Talent: 2 named leaders on record · 2 C-suite/founder profiles curated rank vs industry peers · Fliar Intelligence Index 40/100 | $26M | 4 mo ago | 3 | Tobie Hitchcock Co-Founder & CEO | Apple iCloud MailGoogle WorkspaceEmotion+17 | Top 1M | — | 3 launchs |
| 10 | Abiquo Cloud and Container Management Platform | $25M | 82 mo ago | 4 | — | — | — | — | — |
| 11 | HASH Developer of knowledge graph software for structured data management automation | $12M | 22 mo ago | 31 | Joel Spolsky Co-Founder & Director | SentryZendeskApple iCloud Mail+17 | Top 10M | — | — |
| 12 | Ozone Provider of open source API platform for financial services 40Growth top 35%Talent top 38%Funding top 39%Tech top 50% All 7 signals ▾Growthtop 35% Talenttop 38% Fundingtop 39% Techtop 50% Globalbottom 32% Marketbottom 29% Newsbottom 22% Growth: Fresh capital in last 24 mo Talent: 2 named leaders on record · 2 C-suite/founder profiles curated rank vs industry peers · Fliar Intelligence Index 40/100 | $11M | 7 mo ago | — | Freddi Gyara Co-Founder & CTO | WordPressApple iCloud MailGoogle Workspace+27 | Top 10M | — | 1 launch |
| 13 | IOTech Developer of open edge data platform for industrial edge solutions 57Talent top 28%Innovation top 32%Moat top 39%Product top 40% All 9 signals ▾Talenttop 28% Innovationtop 32% Moattop 39% Producttop 40% Fundingtop 43% Techtop 44% Growthtop 45% Marketbottom 43% Globalbottom 39% Talent: 3 named leaders on record · 3 C-suite/founder profiles curated Innovation: 2 product lines · Deep-tech classification: Tech Hardware rank vs industry peers · Fliar Intelligence Index 57/100 | $10M | 26 mo ago | 37 37 → 51 (+38%) | Anna Duong Co-Founder & CTO | WordPressMySQLPHP+25 | Top 5M | — | 4 launchs |
| 14 | Colony Provider of open source and blockchain-based solutions for organisations | $10M | 52 mo ago | 23 | — | WebflowHerokucore-js+13 | Top 50M | — | — |
| 15 | AppMobi Threat detection and remediation solution | $7M | 132 mo ago | 14 | — | WebflowTypeScriptZone.js+9 | Top 50M | — | — |
| 16 | Syntasso Developer of a framework for building internal developer platforms | $7M | 32 mo ago | 8 | Christopher Hedley Co-Founder & VP Engineering | WixSentryEnvoy+19 | Top 50M | — | — |
| 17 | shuttle Cloud based application development and deployment solution 11Talent top 38%Funding top 40%Moat top 47%Global bottom 40% All 7 signals ▾Talenttop 38% Fundingtop 40% Moattop 47% Globalbottom 40% Patentsbottom 30% Innovationbottom 25% Marketbottom 20% Talent: 2 named leaders on record · 2 C-suite/founder profiles curated Funding: Raised $6.0M across 1 rounds · 1 rounds over 1 yrs (1.0/yr) rank vs industry peers · Fliar Intelligence Index 11/100 | $6M | 8 mo ago | 1 | Christos Hadjiaslanis Co-Founder | — | — | 2 patents Automated shuttlecock retrieval, storage, and dispensing systems for badminton play | — |
| 18 | Cloudsoft Platform offering cloud orchestration software | $6M | 123 mo ago | 29 | Duncan Johnston Watt Founder & CEO | HubSpot CMS HubApple iCloud MailGoogle Workspace+22 | Top 10M | 6 patents Self‑managing distributed network mediation and data flow orchestration for telecom infrastructure | — |
| 19 | Webiny Open-source content management platform | $4M | 58 mo ago | 2 | Goran Candrlic Co-Founder | AceVarnishAmazon Web Services+24 | Top 5M | — | 8 launchs |
| 20 | ChaosIQ Developer of a platform to build chaos experiments | $4M | 70 mo ago | 5 | Russ Miles Co-Founder & CEO | — | — | — | — |
| 21 | Aero Commerce An open-source software tool to create online stores | $3M | 64 mo ago | 13 13 → 8 (-38%) | — | StatamicPHPLaravel+7 | Top 50M | — | — |
| 22 | PartyKit Open source based application deployment platform | $2M | 32 mo ago | 2 | Sunil Pai Founder | VercelAstroVercel Analytics+6 | Top 5M | — | — |
| 23 | Cloud 66 Deployment solution for Rails & Node apps | $2M | 140 mo ago | 4 | — | Apple iCloud MailGoogle WorkspaceHeadless UI+21 | Top 10M | 2 patents Provides secure remote access and virtualized shell execution for data/programs | — |
| 24 | ENGYS Open Source engineering analysis and simulation software | $2M | 43 mo ago | 12 | — | WordPressMySQLPHP+29 | Top 10M | — | 3 partnerships |
| 25 | Fliplet Enterprise app creation and management software | $746K | 134 mo ago | 19 | — | WordPressApple iCloud MailGoogle Workspace+34 | Top 5M | — | — |
| 26 | Canonical Provider of open-source operating systems, cloud computing, and related services | $348K | 125 mo ago | 174 | — | Apple iCloud MailTinyMCEUbuntu+15 | Top 500k | 22 patents Touchscreen graphical user interface transitions and interaction design | — |
| 27 | Flagsmith Provider of an open-source feature flag management platform for enterprises | $130K | 68 mo ago | 11 | — | WebflowAmazon Web ServicesTikTok Pixel+23 | Top 5M | — | 1 job opening |
| 28 | Heroic Labs Backend service provider for game developers | $120K | 132 mo ago | 7 | — | HugoTailwind CSSGoogle Cloud+16 | Top 5M | — | 1 launch |
Top 12 Open Source companies in United Kingdom
#1
Series C · London, England · founded 2013 · 14 employees$101.4Mraised▾
Balena, fka Resin, is a provider of an infrastructure needed to develop, deploy, and manage fleets of connected devices at scale. Its chief offering is balenaCloud which is a container-based platform for deploying IoT applications. In addition, the ecosystem comprises of balenaOS which is an operating system tailored for containers, balenaEtcher which is an open source tool to make device provisioning easy and to flash balenaOS images on the devices, balenaFin which is a carrier board for the Raspberry Pi module and comes with reliable storage, industrial power, flexible networking, real-time and low-power capabilities, among others. As of November 2018, the pricing of the platform starts at $99 per month. Clientele includes Intale, Pact, Enerbrain, Sense, TAPP, Open Energi, among others.
- Jan 2026Series C—
- Sep 2019Series B$53.6M
- Jul 2019Series B$21.1M
- Jun 2018Series B$5M
#2
Series A · London, England · founded 2021 · 3 employees$26Mraised▾
Developer of a multi-model database for AI agents and applications. The database unifies document, graph, time-series, relational, geospatial, and key-value data models. It offers integrated search and retrieval capabilities, including vector, full-text, and hybrid search. The platform provides real-time subscriptions, event triggers, and streaming updates. It also features built-in security with access controls and compliance.
- Feb 2026Series A$23M
- Jun 2024Series A$20M
- Nov 2022Seed$6M
#3
Series A · London, England · founded 2017$10.8Mraised▾
Provider of open source API platform for financial services. The company offers strategic imperative for all banks and financial institutions, open banking APIs for management of the API platform, and standard-based API’s that can handle the complexity of open banking.
- Nov 2025Series A—
- Dec 2023Series A$11.7M
#4
Seed · London, England · founded 2021 · 45 employees$206Mraised▾
Developer of generative AI models for image, video, audio, and 3D. These models are designed for deployment across various platforms, including self-hosted, licensed, API, and cloud-based services. The company provides tools for marketing, entertainment, and gaming, focusing on customizable workflows and enterprise-level solutions. It offers resources such as a learning hub and customer stories to support users.
- Jun 2024Seed$80M
- Jun 2023Seed—
- Sep 2022Seed$101M
#5
Seed · London, England · founded 2020 · 1 employees$6Mraised▾
Cloud based application development and deployment solution. It enables users to develop and deploy applications using the Rust framework. It provides infrastructure definitions from code function signatures and annotations to build the backend. It connects with databases to develop a URL shortener.
- Oct 2025Seed$6M
#6
Series A · London, England · founded 2019 · 31 employees$12.5Mraised▾
Developer of knowledge graph software for structured data management automation. The platform integrates information from various sources to create self-maintaining knowledge graphs. It provides tools for mapping processes, automating workflows, and enabling agentic artificial intelligence. The system supports data synchronization, granular access permissions, and provenance tracking for information. It allows third-party artificial intelligence assistants to query connected data while maintaining privacy and security protocols. The software facilitates retrieval augmented generation and provides audit capabilities for business operations.
- Jul 2024Series A$10M
- Jun 2020Seed$2.5M
#7
Series C · London, England · founded 2014 · 22 employees$40.8Mraised▾
Tyk is an API management platform that consists of an open source API gateway, analytics unit, dashboard and a developer platform. The dashboard allows the user to maintain, manage, promote, and protect APIs using the gateway combined. It comes with built-in analytics tool for providing the user with actionable information about how the API is being consumed. The company claims that their gateway is capable of handling approximately 2,000 requests per second with sub 85ms latency. The platform can be deployed on premises, hosted on the cloud, or offered as a hybrid solution.
- May 2024Series C—
- Sep 2021Series C$35M
- Apr 2019Series A$5M
- Feb 2017Seed$670K
#8
Series B · Shoreditch, England · founded 2011 · 46 employees$39.1Mraised▾
Open source framework for deploying ML models. The cloud-based solution converts ML models or language wrappers into production REST or GRPC microservices. It provides scaling solutions to the production of models and features ML tools such as advanced metrics, request logging, explainers, outlier detectors, AB Tests, canaries, and more.
- Mar 2023Series B$24.2M
- Nov 2020Series A$9.4M
- Jan 2019Seed$5.4M
- 2016Seed$120K
#9
Series B · Newcastle Upon Tyne, England · founded 2010 · 37 employees$10Mraised▾
Developer of open edge data platform for industrial edge solutions. The platform facilitates data accessibility, actionability, and manageability for industrial applications. It offers connectivity, processing, and management capabilities. The platform allows users to connect to devices, acquire data, and securely share it with applications. It supports data processing services, hosting edge applications, and utilizing technologies. The platform automates the management of edge nodes, applications, and connected devices.
- Mar 2024Series B$2.6M
- Aug 2023Series B—
- Dec 2022Series A$8.1M
- Aug 2019Series A$7.5M
#10
Acquired · London, England · founded 2009 · 61 employees$74.9Mraised▾
Platform that provides SaaS based solutions for derivatives risk analytics. It provides an open source platform for derivatives risk management and analytics to the financial services industry, for use in the derivatives OTC markets. The company refers to its solutions as risk service and its products cover ETD & OTC margin calculations, bilateral OTC margining, and derivatives.
- Feb 2022Series E$21M
- Apr 2019Series D$10M
- Jan 2017Series D$1M
- Oct 2016Series D$13.3M
#11
Series B · London, England · founded 2016 · 128 employees$52.3Mraised▾
Decentralized team messaging app for enterprises. Its app also allows users to share photos and files and provides end to end messaging solutions for enterprises. Its mobile app is available for both iOS and Android devices and a web app for Windows and macOS. It allows users to communicate securely and collaborate in real time, making it suitable for businesses and organizations that prioritize data sovereignty and security.
- Jul 2021Series B$30M
- Apr 2020Series A$4.6M
- Sep 2019Series A$8.5M
- Jan 2018Seed$5M
#12
Seed · London, England · founded 2021 · 8 employees$7.1Mraised▾
Developer of a framework for building internal developer platforms. The framework enables co-creation of platform capabilities tailored to an organization's needs. It provides a contract between application and platform teams through the creation of promises. The framework offers workflows to codify organizational policy, compliance, and governance, enabling consistent application. It also simplifies operations across different environments and clusters.
- Oct 2023Seed—
- Oct 2023Seed—
- Oct 2023Seed—
- Oct 2023Seed—
Funding & investor landscape
Notable founders
Market landscape — 10 sub-themes by coverage
Share of Open Source coverage by sub-theme.
Regulatory-risk over time rising
Funding & growth over time
funding rising · growth rising
Common questions
Rohit lives in the feed. He covers what's moving right now — the funding rounds, launches and shifts breaking across the trade press — and ties them back to where the sector is heading.