# Top 35 Developer Tools Startups Founded in 2021 by Funding (2026)

> The 35 best-funded developer Tools startups founded in 2021, ranked by total funding raised: $665M combined.

Source: https://millionrounds.com/top-lists/developer-tools-startups-founded-2021 (Millionrounds; every figure on the page links to its filing or article)

- 1 [**Convex** Convex is a San Francisco-based company that offers an open-source reactive backend platform designed for web developers.](https://millionrounds.com/company/convex) Convex is a San Francisco-based company that offers an open-source reactive backend platform designed for web developers. *Founded* 2021 San Francisco, United States **$120M** last round Aug 2026
- 2 [**Ox Security** Ox Security is the first end-to-end security solution to prevent attacks across your software.](https://millionrounds.com/company/ox-security) Ox Security is the first end-to-end security solution to prevent attacks across your software. *Founded* 2021 Tel Aviv, United States **$60M** last round May 2025
- 3 [**AirOps** AirOps is an enterprise-level content engineering platform that specializes in AI search growth.](https://millionrounds.com/company/airops) AirOps is an enterprise-level content engineering platform that specializes in AI search growth. *Founded* 2021 San Francisco, United States **$56M** last round Nov 2025
- 4 [**Method Financial** Method Financial is a financial connectivity API for consumer liability data + payments](https://millionrounds.com/company/method-financial) Method Financial is a financial connectivity API for consumer liability data + payments *Founded* 2021 New York, United States **$42M** last round Jan 2025
- 5 [**RISC Zero.** RISC Zero is a Seattle-based software development company founded in 2021.](https://millionrounds.com/company/risc-zero) RISC Zero is a Seattle-based software development company founded in 2021. *Founded* 2021 Seattle, United States **$40M** last round Jul 2023
- 6 [**Product Science** Product Science is a deeptech startup founded in 2021, based in Los Angeles, California.](https://millionrounds.com/company/product-science) Product Science is a deeptech startup founded in 2021, based in Los Angeles, California. *Founded* 2021 Los Angeles, United States **$35M** last round Jan 2023
- 7 [**Flox** Flox is a software development platform that creates reproducible environments for the entire software lifecycle.](https://millionrounds.com/company/flox) Flox is a software development platform that creates reproducible environments for the entire software lifecycle. *Founded* 2021 New York, United States **$29M** last round Sept 2025
- 8 [**Reflex** The Reflex technology platform connects top-retail associates with retailers when they need staffing help.](https://millionrounds.com/company/reflex) The Reflex technology platform connects top-retail associates with retailers when they need staffing help. *Founded* 2021 United States **$28M** last round Oct 2026
- 9 [**Stainless** Stainless is building the platform for high-quality, easy-to-use APIs](https://millionrounds.com/company/stainless) Stainless is building the platform for high-quality, easy-to-use APIs *Founded* 2021 New York, United States **$25M** last round Dec 2024
- 10 [**Variance** Variance is an AI-powered risk intelligence platform designed to help enterprises detect and manage fraud, user-generated content violations, and marketplace abuse.](https://millionrounds.com/company/variance) Variance is an AI-powered risk intelligence platform designed to help enterprises detect and manage fraud, user-generated content violations, and marketplace abuse. *Founded* 2021 San Francisco, United States **$25M** last round Apr 2026
- 11 [**Junction** Developers at leading digital health companies, from Metabolic clinics to Longevity, use Junction to remotely access granular health data from wearables and lab tests.](https://millionrounds.com/company/junction) Developers at leading digital health companies, from Metabolic clinics to Longevity, use Junction to remotely access granular health data from wearables and lab tests. *Founded* 2021 New York, United States **$21M** last round Mar 2025
- 12 [**DevZero** DevZero, based in Seattle, is a software development startup focused on enhancing developer productivity and optimizing cloud infrastructure.](https://millionrounds.com/company/devzero) DevZero, based in Seattle, is a software development startup focused on enhancing developer productivity and optimizing cloud infrastructure. *Founded* 2021 Seattle, United States **$21M** last round Jan 2023
- 13 [**Decodable** Decodable is a serverless data integration and engineering platform for streaming data.](https://millionrounds.com/company/decodable) Decodable is a serverless data integration and engineering platform for streaming data. *Founded* 2021 San Francisco, United States **$20M** last round Feb 2022
- 14 [**Salsa** Salsa, founded in 2021 by Juan Barroso and John Kramer, is an embedded payroll provider based in San Francisco, California.](https://millionrounds.com/company/salsa) Salsa, founded in 2021 by Juan Barroso and John Kramer, is an embedded payroll provider based in San Francisco, California. *Founded* 2021 San Francisco, United States **$20M** last round Apr 2025
- 15 [**TrueFoundry** TrueFoundry provides the fastest framework for Post model Pipeline to Data Scientists and ML Engineers.](https://millionrounds.com/company/truefoundry) TrueFoundry provides the fastest framework for Post model Pipeline to Data Scientists and ML Engineers. *Founded* 2021 Hayward Park, India **$19M** last round Feb 2025
- 16 [**Agave Games** Agave Games is a mobile gaming studio based in Istanbul, Turkey, founded in 2021 by four experienced game developers.](https://millionrounds.com/company/agave-games) Agave Games is a mobile gaming studio based in Istanbul, Turkey, founded in 2021 by four experienced game developers. *Founded* 2021 Istanbul, Türkiye **$18M** last round Dec 2024
- 17 [**Herald** Herald builds digital infrastructure for commercial insurance.](https://millionrounds.com/company/herald) Herald builds digital infrastructure for commercial insurance. *Founded* 2021 Boston, United States **$12M** last round Oct 2024
- 18 [**Flexpa** Flexpa allows digital health apps to connect to new patient access APIs.](https://millionrounds.com/company/flexpa) Flexpa allows digital health apps to connect to new patient access APIs. *Founded* 2021 San Francisco, United States **$8.6M** last round Nov 2022
- 19 [**Cerebrium** Cerebrium is a modern data and AI platform for your business that doesn't require an entire data team.](https://millionrounds.com/company/cerebrium) Cerebrium is a modern data and AI platform for your business that doesn't require an entire data team. *Founded* 2021 London, South Africa **$8.5M** last round Jul 2025
- 20 [**Svix** Svix is an open-source webhooks-as-a-service platform founded in 2021, designed to help companies send, receive, and test webhooks efficiently and securely.](https://millionrounds.com/company/svix) Svix is an open-source webhooks-as-a-service platform founded in 2021, designed to help companies send, receive, and test webhooks efficiently and securely. *Founded* 2021 San Francisco, United States **$7.8M** last round Feb 2023
- 21 [**Cerbos** Cerbos is an enterprise authorization management platform founded in 2021 and based in London, UK.](https://millionrounds.com/company/cerbos) Cerbos is an enterprise authorization management platform founded in 2021 and based in London, UK. *Founded* 2021 London, United Kingdom **$7.5M** last round Apr 2023
- 22 [**configure8** configure8 is a commercial internal developer portal platform that helps engineering teams build software more efficiently.](https://millionrounds.com/company/configure8) configure8 is a commercial internal developer portal platform that helps engineering teams build software more efficiently. *Founded* 2021 McLean, United States **$7.2M** last round Sept 2022
- 23 [**Dotfile** Dotfile is a Paris-based fintech and regulatory technology startup founded in 2021 by Vasco Alexandre and Titouan Benoit.](https://millionrounds.com/company/dotfile) Dotfile is a Paris-based fintech and regulatory technology startup founded in 2021 by Vasco Alexandre and Titouan Benoit. *Founded* 2021 Paris, France **$6.7M** last round Sept 2024
- 24 [**Toolpath** Toolpath is an AI-driven software company founded in 2021, based in Atlanta, Georgia.](https://millionrounds.com/company/toolpath) Toolpath is an AI-driven software company founded in 2021, based in Atlanta, Georgia. *Founded* 2021 Atlanta, United States **$6.6M** last round May 2025
- 25 [**Grafbase** Grafbase is an edge-native GraphQL platform that integrates multiple data sources into a single, high-performance API.](https://millionrounds.com/company/grafbase) Grafbase is an edge-native GraphQL platform that integrates multiple data sources into a single, high-performance API. *Founded* 2021 San Francisco, United States **$5.0M** last round Oct 2022
- 26 [**Lost Lake Games** Lost Lake Games is an independent studio committed to making games that blaze new trails and spark the next adventure.](https://millionrounds.com/company/lost-lake-games) Lost Lake Games is an independent studio committed to making games that blaze new trails and spark the next adventure. *Founded* 2021 Seattle, United States **$5.0M** last round Feb 2022
- 27 [**Mentum** Mentum is an API for fintech companies that offers investment services.](https://millionrounds.com/company/mentum) Mentum is an API for fintech companies that offers investment services. *Founded* 2021 San Francisco, United States **$4.2M** last round May 2022
- 28 [**Rowy** Build your product backend as easy as using spreadsheets.](https://millionrounds.com/company/rowy) Build your product backend as easy as using spreadsheets. *Founded* 2021 San Francisco, United States **$3.0M** last round Dec 2022
- 29 [**Haste Arcade** The Haste Arcade is a marketplace where gamers discover the hottest new ILP games.](https://millionrounds.com/company/haste-arcade) The Haste Arcade is a marketplace where gamers discover the hottest new ILP games. *Founded* 2021 Hermosa Beach, United States **$1.5M** last round Jun 2022
- 30 [**Pelm** Pelm provides digital infrastructure to develop API for accessing and managing user's energy data.](https://millionrounds.com/company/pelm) Pelm provides digital infrastructure to develop API for accessing and managing user's energy data. *Founded* 2021 San Francisco, United States **$500K** last round Mar 2022
- 31 [**Sparkles** Sparkles is the open NFT market on Songbird and the Flare Network.](https://millionrounds.com/company/sparkles) Sparkles is the open NFT market on Songbird and the Flare Network. *Founded* 2021 United States **$500K** last round Mar 2026
- 32 [**Invisible CodeBuddy** Invisible CodeBuddy is a SAAS platform that offers custom-built codeKits to help users gain an advantage on coding tasks.](https://millionrounds.com/company/invisible-codebuddy) Invisible CodeBuddy is a SAAS platform that offers custom-built codeKits to help users gain an advantage on coding tasks. *Founded* 2021 Lincoln, United States **$490K** last round Dec 2023
- 33 [**Bclipse** Bclipse is a creative game platform where anyone can become a creator with a game development engine.](https://millionrounds.com/company/bclipse) Bclipse is a creative game platform where anyone can become a creator with a game development engine. *Founded* 2021 Seongnam **$447K** last round Apr 2021
- 34 [**Metabob** Automatically detect severe and more relevant problems and vulnerabilities early in the development process with the help of AI.](https://millionrounds.com/company/metabob) Automatically detect severe and more relevant problems and vulnerabilities early in the development process with the help of AI. *Founded* 2021 United States **$247K** last round Sept 2023
- 35 [**beecrowd** The Ecosystem where Innovative Companies find the best Tech Talent](https://millionrounds.com/company/beecrowd) The Ecosystem where Innovative Companies find the best Tech Talent *Founded* 2021 São Paulo, Brazil **$100K** last round Jun 2025

**Total funding** how the list is ranked

**15 November 2026** updated nightly

**Rounds we track** source: Millionrounds

Companies founded in 2021 whose funding rounds we classed in this sector, ranked by the total they have raised in rounds we hold. Nobody pays to be on a list.

## Who backed them?

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## More developer tools lists

[See all](https://millionrounds.com/top-lists?t=Developer%20Tools)

[*C* *A* *P* **Developer Tools startups in San Francisco** 94 companies · $14B](https://millionrounds.com/top-lists/developer-tools-startups-san-francisco)[*C* *F* *FA* **Developer Tools startups that raised in 2026** 89 companies · $12B in 2026](https://millionrounds.com/top-lists/developer-tools-startups-raised-2026)[*F* *S* *P* **Developer Tools startups founded in 2020** 56 companies · $3.2B](https://millionrounds.com/top-lists/developer-tools-startups-founded-2020)[*A* *T* *L* **Developer Tools startups founded in 2022** 43 companies · $5.2B](https://millionrounds.com/top-lists/developer-tools-startups-founded-2022)[*P* *L* *C* **Developer Tools startups founded in 2023** 34 companies · $3.6B](https://millionrounds.com/top-lists/developer-tools-startups-founded-2023)[*M* *A* *H* **Developer Tools startups founded in 2018** 33 companies · $976M](https://millionrounds.com/top-lists/developer-tools-startups-founded-2018)[*T* *M* *FA* **Developer Tools startups in the United Kingdom** 30 companies · $836M](https://millionrounds.com/top-lists/developer-tools-startups-united-kingdom)[*S* *C* *S* **Developer Tools startups founded in 2019** 27 companies · $219M](https://millionrounds.com/top-lists/developer-tools-startups-founded-2019)

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[*GV* *V* *RP* **Health startups worldwide** 12,811 companies · $81B](https://millionrounds.com/top-lists/health-startups)[*O* *A* *X* **AI startups worldwide** 10,238 companies · $830B](https://millionrounds.com/top-lists/ai-startups)[*GV* *V* *RP* **Biotech startups worldwide** 7,127 companies · $70B](https://millionrounds.com/top-lists/biotech-startups)[*D* *B* *FT* **Big data startups worldwide** 3,812 companies · $220B](https://millionrounds.com/top-lists/big-data-startups)[*AF* *R* *S* **Fintech startups worldwide** 3,200 companies · $94B](https://millionrounds.com/top-lists/fintech-startups)[*O* *A* *B* **AI startups that raised in 2026** 2,922 companies · $540B in 2026](https://millionrounds.com/top-lists/ai-startups-raised-2026)[*FT* *CE* *P* **Energy providers startups worldwide** 2,808 companies · $152B](https://millionrounds.com/top-lists/energy-providers-startups)[*A* *P* *O* **Marketing tech startups worldwide** 2,728 companies · $28B](https://millionrounds.com/top-lists/marketing-tech-startups)