Developer Tools Startups funded by Y Combinator (YC) in the San Francisco Bay Area that are currently hiring 2025

Apollo GraphQL is the leader in open source and commercial GraphQL technologies. Apollo’s open-source GraphQL client, server, and gateway are downloaded more than 17M times per month and used in production by over 30% of the Fortune 500. Customers like Walmart, Expedia, Glassdoor, Audi, and PayPal, use the Apollo Graph Platform to unify their GraphQL efforts, collaborate on graph development, and safely iterate on their graphs. Based in San Francisco, Apollo is backed by Insight Partners, Andreessen Horowitz, Matrix Partners, Trinity Ventures, Y Combinator and individual investors.

HackerRank, the developer skills company, helps businesses attract, evaluate and hire the best technical talent from around the world. More than 2,800 customers across all industries, including over 25% of the Fortune 100, rely on HackerRank to raise their hiring bars. More than 18 million developers (approximately 40% of the global developer population) trust HackerRank to learn and showcase their coding skills. Every second, two developers complete a HackerRank code submission, or 185,000 per day.

OneSignal is the leading omnichannel customer engagement solution, powering personalized customer journeys across mobile and web push notifications, in-app messaging, SMS, and email. Our easy-to-use interface empowers content creators to focus on quality user engagement instead of complex implementation. Our powerful platform enables over a million businesses to deliver 10 billion messages daily and 1 in 7 new apps launches using OneSignal! We support companies in 140 countries, including Zynga, USA Today, Bitcoin.com, Upwork, Tribune, and many more - from startups and small businesses just getting off the ground to established companies communicating with millions of customers.

Built by electrical engineers for electrical engineers, SnapMagic removes monotony so that engineers can do their best work. SnapMagic’s electronic component data is used by over 1.5 million engineers across the world’s largest organizations. Its new AI Copilot will change the way that every engineer designs electronics. Join at www.snapmagic.com.

Bitmovin has been a first mover in almost every significant development in online video, from building and deploying the world’s first (and fastest) commercial adaptive streaming (MPEG-DASH/HLS) HTML5 Player, to being the first to achieve 100x realtime encoding speeds in the cloud. Bitmovin provides HEVC as well as VP9 live streaming with 60FPS and 4K resolution, and built the first containerized video encoding solution with Docker and Kubernetes. Bitmovin products are completely in-house developed, easy and fast to integrate and highly customizable. In combination with our great support, documentation and SLAs, this is a true enterprise offering. To find out more about Bitmovin’s video infrastructure solutions, or about any individual products, contact sales@bitmovin.com, or visit our website: bitmovin.com

Mux is an API-first video platform designed by experts to make world-class video streaming and analytics possible for every development team. Self-optimizing videos take the guesswork out of encodings, delivery, and renditions. Mux makes your video look beautiful on every device, every time. We offer two products, Mux Video and Mux Data. Mux Video is a simple API to advanced video streaming. Powered by data and designed by video experts, Mux Video makes beautiful video possible for every development team. Post a video or live stream with a single API call, and watch it within seconds. Mux Video handles the encoding, storage, and delivery. QoE and performance analytics provided by Mux Data is included by default for every Mux video stream.This real-time data is used to create the right renditions for every device and title, resulting in greater reliability and better viewer experiences. Mux Data is a Quality of Experience analytics platform that measures the performance metrics that actually matter to viewers: rebuffering, startup time, video quality, and errors. Our intuitive dashboard quickly gives users the insight to find issues and make improvements through features like A/B testing, industry-wide scores, alerts, and detailed information about every single video view. The product works out of the box on HTML5, iOS, Android, and major OTT platforms. All data is available via exports and APIs, making it easy to integrate Mux Data into other systems.

Daily is real-time voice, video, and AI for developers. Our cross-platform SDKs and global infrastructure enable ultra-low latency, highest quality experiences for developers building real-time voice and video AI agents. Our platform also supports integration of traditional voice/video calls, in addition to AI agent experiences.

From MIT's App Inventor and YCombinator's W2016 batch, Thunkable allows anyone to build powerful native apps. With Thunkable, it's simple to design, and simple to code-- simply drag and drop to create fast, native, reliable apps. You don't need to download large development suites, command-line kits, or simulators. You can use the many built-in app templates as they are, or make changes. Make your changes online and see them on your device instantly with the Thunkable mobile app. Upload your apps directly to the Play Store or App Store or send them to friends!

Nanonets is an AI-driven solution that automates document processing and data extraction workflows. Leveraging advanced Optical Character Recognition (OCR) and deep learning models, Nanonets helps companies automate document-heavy business processes like accounts payable, order processing and insurance underwriting. Nanonets processes unstructured documents such as invoices, receipts, purchase orders, contracts, claims, and forms and converts them into structured output.

Retool is the fast way to build internal tools.

DreamCraft enables anyone to create, publish, and monetize video games. The company’s core product is a code-free game creation platform, bundled with high quality art assets. DreamCraft is backed by March Capital, Makers Fund, Tencent Corporation, Y Combinator, and other top investors in the gaming space. The company was founded in 2018 and now has a global team of 20+ people with half remote and half based in Silicon Valley.

Alpaca is an API infrastructure and licensed financial services company that allows developers and businesses to offer stock and crypto investing to their end-customers. We work with more than 100 companies across the globe to enable their investing products, and our mission is to provide financial services to everyone on the planet. Alpaca’s globally distributed team consists of developers, traders, and brokerage business specialists and backed by a group of well-capitalized investors including Portage Ventures, Spark Capital, Tribe Capital, Unbound, Social Leverage, Horizons Ventures, Y Combinator as well as highly experienced industry angel investors and founders. We are also very tech-enthusiastic with notable track records in open-source and startup communities.

Memfault is the first IoT reliability platform that empowers teams to build more robust devices with software at scale. We believe that device reliability engineering will transform how developers build and operate IoT and edge devices with more productivity and more collaboration. As IoT applications continue to grow in complexity, it is more important than ever for developers to have Memfault’s performance monitoring, device debugging, and OTA update capabilities built into their fleet of devices for proactive device operations. We built Memfault to enable developers with a more scalable and sustainable process to accelerate go-to-market, de-risk product launches, cut product costs, and deliver overall superior products.

Rosebud is building the AI Roblox. We will make it 1000X easier for a community of game devs to create and enjoy the games of their dreams. ‍ We’re a team of PhD researchers, creatives and engineers building the generative AI platform to enable game creation at the speed of thought. We believe all media creation will be done via generative methods in a few years. We're building that future.

We are working on the software that will power the next generation of Cloud Computing (Edge Computing) platforms using WebAssembly. You can see us as a mix between Docker (but 100x more performant in startup time, and with 100x more lightweight containers), npm (we released the first WebAssembly package manager: wapm.io) and the JVM (but more universal).

MindsDB is a fast-growing AI startup headquartered in San Francisco, California. As a leading innovator bringing AI and Data together, our passion is empowering companies to easily build AI capabilities that can Think, Understand and Orchestrate: enabling teams to move from prototyping & experimentation to production in a fast & scalable way. MindsDB was founded in 2017 by Adam Carrigan and Jorge Torres, inspired by Ian M. Banks's Culture series, in which super AI systems called Minds collaborate with other forms of life to accomplish incredible goals. Starting as an Open-Source project, MindsDB has grown to be one of the most widely used AI-Data platforms in the world, with a growing community and more than 700 contributor developers from every corner of the globe. We are backed with over $55M in funding from Mayfield, Benchmark, YCombinator, and nVidia. MindsDB is also recognized by Forbes as one of America's most promising AI companies (2021) and by Gartner as a Cool Vendor for Data and AI (2022).

Manage the words across your team’s product from design to production.

​​Cortex is an internal developer portal built to accelerate the path to engineering excellence. Companies like Docker, TripAdvisor, and Dropbox use Cortex to catalog, score, and assign action to improve service quality and velocity, so devs can get back to work that drives the business forward.

Roboflow enables developers to make the world programmable. Use our tools to build better datasets (collect image, video / annotate), models (foundation and fine tuned small models), and deployments (self hosted, edge, APIs, SDKs) for computer vision. Over 250k developers, including those from over half the Fortune 100, build with our open source and hosted tools. Build with us: https://app.roboflow.com Hack with us: https://roboflow.slab.com/public/posts/roboflow-hackathons-external-u478m1iz Work with us: roboflow.com/careers

SuperTokens is building open source authentication (as an alternative to Auth0, Firebase and AWS Cognito). Add secure, hassle free authentication to your app in 1 day. We enable startups to launch quicker and focus on their core product offering 1. We're easier to implement as we take a modular approach - making it possible to pick only the features you need for your use case. This means you need not worry about complications associated with other features (eg: SSO and OAuth if you don’t need it) and this in turn makes it easier to implement and manage SuperTokens. 2. Developer's can own and manage their user's data. 3. SuperTokens can be run on your premise for free and also has a generous hosted tier for those who dont want to manage it themselves. SuperTokens is being used by hundreds of developers across the globe.

Seam lets developers connect and control 3rd-party connected devices like door locks, thermostats, and more.

Safepay provides a single integrated payments solution that interoperates with local and international payment options. Our current focus is to serve businesses and individuals in Pakistan and neighboring economies.

Many workflow builders and automation tools have support for adding logic to your processes, but get complicated quick– to the point where process owners are unable to edit them directly and require specialist services. Rulebricks separates decision-making logic from your workflows, giving your team a clear visual, spreadsheet-like interface to manage the changing rules that drive your business, and use those rules as API endpoints, visual forms, and in automation tools like Zapier.

We're building a visual application development platform to dramatically improve the time to market and quality of digital experiences. FlutterFlow helps companies and product teams improve developer efficiency, accelerate project timelines, and reduce costs for large-scale business applications. Our customers include some of the largest banking, consulting, telecom, and manufacturing companies in the world. We have more than 1.3M users in more than 200 countries and regions around the world. We’re a remote first team headquartered in the San Francisco Bay Area. We have offices in Mountain View, New York City, and Singapore.

Openlayer helps you test and monitor high-quality AI systems.

Rootly is a modern on-call and incident management platform used by top YC companies like Dropbox, Lattice, Webflow, Faire, but also Figma, LinkedIn, NVIDIA and 100s more.

OneSchema is the embeddable CSV importer used by product and engineering teams to save months of development time and to automate CSV mapping, validation, and transformation.

Squire is a devtool that works with you by writing pull request descriptions, reviewing PRs, and writing code to implement code review feedback.

Aviator is a developer tool that automates merge workflows and keeps builds healthy. Engineers save up to 5 hours a week and avoid frustration of broken builds. Our users include Slack, Bosch, Lightspeed, Square, Benchling, Figma and many others. For instance, Slack went from 180 master-build failures per quarter to just 1 build failure when they started using Aviator. Our goal is to become the leading brand for developer experience.

GrowthBook is an open source platform to help companies make data-driven product decisions with feature flags and A/B tests. Existing SaaS solutions like LaunchDarkly require a company to send all of their data to them. This results in high costs, data compliance issues, and vendor lock-in. As a result, many companies end up building their own platforms in-house, which can take thousands of hours of work and lots of headaches. To solve this, GrowthBook uses a company's existing data infrastructure and business metrics. We believe feature flags and experimentation are the right way to build products at scale and that they will become a standard part of the development process. GrowthBook is well positioned to be a leader in this growing market.

Sieve is a specialized cloud built for video / audio AI. Every video product today is being overwhelmed by a ton of new use cases that are enabled by AI. Video is unique in that it’s much more compute and data-intensive to process or generate compared to other modalities. This leads to a ton of complexity around the ways models are run, the kinds of extra processing needed to happen around them, and the complexity of pipelines that solve the most valuable use cases in the modality. To this end, Sieve’s strongest and most immediate value proposition comes from being an AI toolkit that solves problems unique to video — unlike generic AI developer tools that might exist today. Video is just the start however. Learn more about our long term vision [here](https://sievedata.com/about/jobs)!

Our mission is to make the web more collaborative. We're not just making collaboration faster—we're crafting it to be the best. Today we’re all using online platforms more than ever before - building, researching, learning, connecting etc. And we're not doing it alone. We're doing it together with other people and machines, turning the internet into the world's biggest team. Yet, the web was built for solo voyages. We saw a shift when platforms like Figma and Google Docs brought a multiplayer approach, breaking down walls and inspiring seamless teamwork. At Velt, we're taking it further. We're on a mission to infuse the magic of collaboration into the fabric of the web—one app at a time. We aim to erase the lines between online and offline co-working, crafting an environment where distance is irrelevant, and 'flow' is the norm. Right now, more than half of work hours are spent on coordination and communication—less on creating. With Velt, we're setting out to reverse these figures, reducing time spent on logistical issues by over 90%. Imagine what we can create when we spend less time talking about work and more time doing it! We're building a better web—a web for us, for our team, for everyone. Join us, and let's accelerate the future of web together 🚀 Our Products: - Velt Collaboration SDK (https://velt.dev/): JS SDK to add powerful collaboration experiences to your own product for your end-users. This helps you ship such experiences ridiculously fast, increase user growth and engagement. - Superflow (https://usesuperflow.com/): JS plugin to enable product, marketing and design teams to comment and collaborate directly on their websites. This helps them iterate and ship their products 10x faster. We’re a team of ex-Googlers. We've launched products like Augmented Reality in Google Search & Maps. Come build a better web with us 🚀

Next-Gen API Documentation with AI Brilliance. Generate Stripe-like API docs in just a few seconds.

Medplum makes it easy to build healthcare webapps that are compliant and interoperability ready. Our open source toolkit allows healthcare providers write apps that are HIPAA compliant, SOC2 certified and FHIR native - streamlining payor connections, health system integrations and more.

Packaged Applications for Any Platform. Bitnami has automated the ability to package, deploy and maintain applications, lowering the barrier to adoption for anyone to deploy and maintain a full spectrum of server applications, development stacks and infrastructure applications in virtually any format. Simply click to deploy any one of 120+ ready-to-run applications from the Bitnami Application Catalog or use Bitnami Stacksmith to package and migrate your custom in-house applications to the cloud. For more information, visit www.Bitnami.com, or follow us on Twitter (@Bitnami) and Facebook.

Your software is your competitive advantage, and your customer experience is everything. Armory Continuous Deployment solutions empower you and your teams to confidently deploy every application, every time; safely and securely, so you can accelerate your time-to-market, increase stability, and decrease customer-impacting issues.

Slapdash brings all your apps together in one place to give you new superpowers. It's a new type of tool that makes modern computer work less tedious and more fun. It's just one neat trick: we make your workflow insanely fast. We have built a low-latency, file-system for your cloud apps as well as the fastest interface in the world to drive it: the Command Bar.

Satsuma is a developer tool for building applications on top of real-time blockchain data. Our product lets developers take decoded data from multiple chains, customize it for their use cases, and access it through API endpoints. Blockchains serve as distributed databases for these products, holding their most important data. However, it’s difficult to access and query that data. We believe this friction is an enormous blocker for web3 developers and that better tooling will enable mass adoption for web3. We’re a founding team of engineers, having built data infrastructure and product as early employees at Airtable, Heap, and Y Combinator.