Developer Tools Startups funded by Y Combinator (YC) 2025

GitLab is the first single application for the entire DevOps lifecycle. Only GitLab enables Concurrent DevOps, unlocking organizations from the constraints of today’s toolchain. GitLab provides unmatched visibility, radical new levels of efficiency and comprehensive governance to significantly compress the time between planning a change and monitoring its effect. This makes the software lifecycle 200% faster, radically improving the speed of business. GitLab and Concurrent DevOps collapses cycle times by driving higher efficiency across all stages of the software development lifecycle. For the first time, Product, Development, QA, Security, and Operations teams can work concurrently in a single application. There’s no need to integrate and synchronize tools, or waste time waiting for handoffs. Everyone contributes to a single conversation, instead of managing multiple threads across disparate tools. And only GitLab gives teams complete visibility across the lifecycle with a single, trusted source of data to simplify troubleshooting and drive accountability. All activity is governed by consistent controls, making security and compliance first-class citizens instead of an afterthought. Built on Open Source, GitLab leverages the community contributions of thousands of developers and millions of users to continuously deliver new DevOps innovations. More than 100,000 organizations from startups to global enterprise organizations, including Ticketmaster, Jaguar Land Rover, NASDAQ, Dish Network and Comcast trust GitLab to deliver great software at new speeds.

Our mission is to make every search interaction meaningful & rewarding, through developer-friendly and enterprise-grade APIs. Algolia is the leading Search & Discovery API for websites and mobile apps. We help the most innovative companies across e-commerce, media and SaaS industries create powerful, relevant and scalable discovery experiences for their users. Unlike other solutions, our hosted platform reduces the complexities of building and scaling a fast, relevant digital experience and helps teams accelerate development time. More than 9,000 companies like Under Armour, Twitch, Periscope, Medium and Stripe rely on Algolia to manage 50+ billion search queries a month. Founded in 2012, we're backed by $184M in funding from Accel Partners, Alven Capital, Point Nine Capital and Storm Ventures. The team is headquartered in San Francisco with offices in Paris, London, New York, and Atlanta. To learn more, visit www.algolia.com. --- We’re looking for talented, passionate people to build the world’s best search technology. As an ownership-driven company, we seek team members who thrive under autonomy and diversity. We're committed to building an inclusive and diverse workplace. We care about each other and the world around us, and embrace talented people regardless of their race, age, ancestry, religion, sex, gender identity, sexual orientation, marital status, color, veteran status, disability and socioeconomic background

Since graduating from YC, Amplitude (W12) has made it to IPO and beyond by helping cutting edge startups become category leaders. We’ve pioneered the digital analytics category to become the go-to solution for AI pioneers (Cruise, Midjourney), apps that touch millions of consumers (Doordash, Coinbase), and the best in B2B (Atlassian, Rippling, Canva). With product analytics, experiment, CDP, session replay, and more, Amplitude’s digital analytics platform shows you what your users love, where they’re getting stuck, and what keeps them coming back. You want to build a generational business, and we have the capabilities and pricing plans to guide you every step of the way. Check out our special deal for YC companies and get started on your analytics journey.

Bubble Lab is an open-source Typescript-native workflow automation platform. Unlike tools that use proprietary JSON, you describe a workflow in natural language, and instantly get both a visual flow and fully-typed TypeScript code side-by-side. It offers built-in observability, testability, and scalability out of the box.

JSX Tool is a browser extension that hooks into your React project, so you can easily locate any React component and file with just a click. This gives developers the ability to articulate visual requests to LLMs that without JSX Tool, are either vague or cumbersome to communicate in English and code snippets. On top of that JSX Tool is a full featured IDE tailored specifically for React Development, so users never have to leave the context of their browser when developing React code.

Captain delivers the most accurate general-purpose retrieval engine for unstructured data. Connect file stores and effortlessly retrieve knowledge with much higher accuracy than RAG (Avg: 78% → 95% + citations).

Castari lets developers deploy AI agents in secure, autoscaling sandboxes with one command. We handle tool/MCP connectors, snapshots, and observability so teams go from prototype to production in hours instead of weeks. Developers focus on building agents, Castari provides the autoscaling sandbox infrastructure to ensure your agents and its tools are secure.

Jarmin.ai is your 24/7 ML eng employee that you hire. Just talk to Jarmin like any other employee and Jarmin handles your AI/ML work from there. Completely hand over full initiatives or individual tasks. Jarmin’s founding team is from Meta SuperIntelligence Labs (Staff Engineers), Apple (Machine Learning Engineer), AWS (scaling infra), Lockheed-Martin (Research), and JPMorganChase (SWE) with experience building AI/ML and automating complex work of Researchers, Data Scientists, ML Engineers with AI.

Sanctum lets you launch new features to agents that mimic your real users. We build AI user models from your session recordings and run them against your changes to surface bugs, UX issues, and performance problems early.

Inspector helps front-end engineers ship faster with AI by automating the most frustrating part of the job — gathering context between the browser and the codebase. Inspector is an AI IDE for front-end that connects your browser and codebase. Inspector lets you select elements visually and prompt changes, giving coding agents access to the same runtime context developers have: visuals, elements, and logs. With Inspector, you’re editing right in the front-end, not buried under tabs and screenshots.

Scott AI is the agentic workspace where teams align on spec before any codegen runs. Teams already use multiple coding agents to build. Different coding agents will continue to evolve and have diverse strengths. An engineer will entrust a long-running agent to add dark-mode end-to-end while they pair carefully with an IDE-based agent to land a critical DB migration. These execution agents cannot be the decision layer because they are biased to their own tool, they are not neutral. Scott AI is the neutral, agent agnostic decision layer for the age of multi agent building. Teams will use Scott as their decision workspace to finally ditch google docs and notion as their primary spec alignment layer.

Lemma enables AI agents to continuously improve from user feedback and production outcomes. Instead of relying on manual prompt tuning and reactive debugging, Lemma detects when an agent’s performance drifts, pinpoints the exact step causing failures, generates optimized prompt candidates, and automatically delivers improvements through our API or by opening a pull request in your codebase. Built by ex-AI engineers who felt this pain firsthand, Lemma turns static agents into self-improving systems, helping teams ship reliable AI products faster with compounding performance gains over time. Deploy 1x. Learn forever.

Rovr streamlines engineering operations by automating intake, triage, routing, and cross-team coordination. It replaces internal forms, manual Slack triage, and scattered docs with an AI front desk that understands requests, assigns owners, updates context, and posts status changes directly into Slack. Rovr’s built-in ops CRM gives teams a single system of record for eng requests — from tooling access to platform incidents to dev-infra workflows — reducing operational drag across the entire org.

Parse lets developers build APIs for any website. Unlike traditional scraping tools that rely on slow, expensive headless browsers, Parse reverse-engineers websites' underlying network requests and generates API endpoints automatically. This makes Parse 10-100x faster and cheaper than browser automation,.

Moss is building the real-time semantic search runtime for conversational and multimodal AI. Our system enables voice agents, copilots, and chat interfaces to retrieve, reason, and respond in sub-10 ms, delivering the responsiveness that makes AI interactions feel truly natural. If you’ve ever built a conversational or voice AI product, you’ve felt the lag. That moment when an agent pauses and the illusion of intelligence breaks. The bottleneck is almost always retrieval. Each query hops across networks and databases, adding delay and cost. Moss eliminates that gap by keeping retrieval close to where the agent runs. Moss runs natively across browsers, mobile devices, and servers with an optimized vector index built in Rust and WebAssembly. It enables teams to build AI products that feel instant, contextual, and adaptive. The experiences that sustain engagement and unlock new kinds of interaction. For our customers, this translates into tangible business value: stronger user retention, higher conversion, and entirely new product categories made possible by real-time understanding. Moss is already powering production pilots across voice AI and developer platforms, achieving sub-10 ms retrieval and 70–90% token savings compared to traditional pipelines.

free codegen from brainrot workflows in your IDE.

Hyperspell (YC F25) gives AI agents memory. It connects to tools like Slack, Gmail, Notion, and Drive so agents can recall, reason, and remember across company knowledge. Developers use Hyperspell’s API to turn disconnected agents into AI coworkers that understand their work. Conor and Manu founded Hyperspell after building their own workplace agent and seeing how limited AI is without memory. They have over 15 years of experience in machine learning and have scaled API-based products to $30M ARR.

Compyle is a less autonomous coding agent that asks before it acts. We're like Cursor or Claude Code - but you won't need to rewrite your codebase every time you use it for more than a small task. We built Compyle because we were frustrated with the direction other coding agents are headed. They're all racing to be more autonomous, running for hours without human input. This doesn't work for real production code. When agents run autonomously, they make countless small decisions that pile up in your codebase. Engineers lose ownership - they don't know what was implemented, can't effectively debug or maintain it, and struggle to build on top of it. The code becomes a black box, and they're forced to throw it away. Compyle keeps engineers in the driver's seat.

Fastshot is a no-code mobile development platform. Our mission is to "Democratize mobile app creation with AI" Anyone can develop a mobile app from idea to App Stores within minutes just by chatting with AI.

Ship reliable agents with confidence. AI agents often fail quietly, picking the wrong tools, looping, hallucinating, and more. The Context Company tells developers when and exactly where their agents fail so issues can be uncovered and fixed fast. It combines traditional observability across traces, tool calls, latency, and costs with the ability to uncover silent failures that standard monitoring misses. Get started with less than 10 lines of code.

Sourcebot is an open source code understanding platform for massive codebases. We’re used by thousands of engineers in some of the largest companies in the world, including NVIDIA, Red Hat, Wikimedia, and Arista Networks. Understanding code, not writing it, is the primary bottleneck for large engineering teams. For developers, this means onboarding onto complex codebases faster. For AI agents, it means getting the necessary code context to minimize hallucinations and maximize cohesion within the wider codebase. Sourcebot solves this by giving developers and AI agents the ability to regex search across millions of lines of code instantly, as well as ask questions across thousands of repos using any flagship reasoning model. Being open source and on-prem, we can get deployed in enterprises within minutes before other tools even get approval. We met a decade ago at McGill University and have been building together full time for over 2 years. We’ve personally felt the pain of understanding large codebases while working at Microsoft, EA, Ubisoft, Google, and Meta.

Metorial is the infra layer for AI integrations. We built the only serverless MCP runtime that can maintain state with sub-second cold starts, built-in security, and monitoring. We make it easy for developers to connect AI agents to apps and data sources at scale.

Soren builds autonomous agents to replace human engineers on manual AI evaluation tasks. Evals are essential for building reliable AI systems, yet they remain incredibly time-consuming. Teams spend countless hours maintaining their evals and digging through piles of logs and traces to debug their systems. At scale, this level of manual work simply isn’t sustainable. Soren changes that with powerful agents that work alongside your team. They reason across test cases and logs to pinpoint root causes, then run targeted experiments to surface better-performing solutions. New test cases are added whenever new behaviors are detected, so engineers can stop doing ad-hoc maintenance. Built by MIT engineers who've published leading research in this space and lived the problem. We're building a future where AI handles the work and humans simply provide oversight.

Dome makes it easy to build on prediction markets like Polymarket and Kalshi. We provide the developer infrastructure to access, analyze, and build on prediction markets. With our unified API, developers can access live and historical data, including granular datasets not available natively, across multiple platforms at once. Dome makes it simple to trade, embed market data into products, and deploy strategies across multiple platforms through one interface.

An automation platform where users can reliably automate web workflows using natural language prompts. We handle two-factor authentication and deterministic playback of workflows, ensuring your workflows don't break.

S2 is a serverless datastore for real-time, streaming data. The more we worked on data systems, the more we felt like there was a missing building block. The seamless experience of object storage simply did not exist for durable streams – so we set out to fix that! S2 reimagines streams as an unlimited and access-controlled web resource. Like if Kafka and S3 had a baby. - Building agents? Use granular streams to persist context in real time, make workflows auditable, and coordinate between agents. - Publishing fast-moving data? Streams support high fanout and can be accessed directly over the internet, so they are a great fit for broadcasting real-time feeds. - Sandboxing? Emit to per-instance streams, and read history or live events just as easily. - Local-first and multiplayer experiences? Propagate updates reliably and efficiently. Stop dealing with clusters, and start streaming.

At Deeptrace, we’re building AI agents that investigate and resolve production alerts end-to-end. Deeptrace cuts through the noise, pinpoints root causes instantly, and gives engineering teams back what they need most: the freedom to build instead of firefighting. In production, we're already seeing a reduction in time spent triaging, investigating, and resolving alerts with some of the fastest growing companies in the world.

Specific lets users build and deploy backends without code. They simply connect their preferred coding agent and we build, deploy and scale a backend for any project automatically.

Lua is the mid-market agent platform. We deliver enterprise reliability with the speed, flexibility, and economics that mid-market companies demand - helping them deploy AI agents that drive sales, support, and operations across everyday channels and tools. We scale through developer agencies and channel partners, enabling rapid distribution without a large enterprise sales motion or scaled forward deployed teams. We think of Lua as an agentOS that abstracts all of the complexity required to launch enterprise grade agents and combine it with the tools needed for these agents to succeed in the real world. Lua was founded by Lorcan O Cathain (CEO) and Stefan Kruger (CTO)- experienced founders who have spent 15 - 20 years each scaling technology companies across emerging markets. We sell to mid-market enterprises and developer agencies in the US and internationally. Developers are increasingly our primary ICP but we run SMB & enterprise sales motions to accelerate our learnings and further develop our product: - SMB ($25- 1k per month): fully automated self-serve agents that handle sales and support for eCommerce companies, hotels, restaurants and general service businesses. If you’ve been on our website you’ve likely seen this. - Enterprise: We directly sell to mid-market (~ $50M- $1BN) businesses across the US and internationally to eat our own dog food and strengthen our platform.

Dedalus Labs is building Vercel for AI Agents. We host MCP servers on our cloud and handle the boring stuff like autoscaling and load balancing so users can go from idea to production in a single click. Our OpenAI-compatible SDK lets users orchestrate complex agentic workflows through one clean API. Route between any LLM provider, connect any MCP tools from our hosted marketplace, and ship in minutes.

Our mission is to build self-improving AI agents. We're here to close the last mile reliability gap. Through calibrated llm judges and automatic evaluations, we help companies optimize their agents 10x faster than doing manual experimentation.

Lotas is building Erdos: a secure, AI-native IDE for data science. Cursor is excellent for software development but it lacks data science-specific tools that are critical to a data scientist’s workflow. Lotas is closing that gap. For our first product, we built Rao: an AI coding assistant into RStudio — an IDE used by up to 5 million data scientists and statisticians who use the R programming language to analyze data. Rao could read, write, and edit code while understanding the user's context (codebase and environmental variables).

Imagine a QA team of 5,000 testers available 24/7 on every new feature you ship. That's Ghostship. Our AI agents will crawl through your product and interact with it like users would to find the bugs (especially edge cases) that lead to churn—all at a fraction of the cost.

Fluidize accelerates R&D for scientists and engineers by using AI to build and run simulations and experiments. Our platform speeds up development pipelines by automating setup, execution, validation, and scaling, allowing engineers to focus on their science.

We help people understand their agent workflows and where they went wrong. We met early on at MIT and built a bunch of projects together for fun. Of course when the AI wave took over, we were excited about agents. We made our own agents, and we always found it annoying figuring out if they consistently worked or not. We believe that it should be easy to know what your agents are doing and why, no matter the use case or the tech stack. So that's exactly what we're helping companies achieve; we started building a few weeks ago and are working with our design partner to get deep observability and insights into their agent executions. The future is autonomous; AI agents will be everywhere. Mohi can make sure that we humans know what these agents are doing.

Kernel is the best place in the world to launch web agents. We handle the hard parts of running browser infrastructure in the cloud so you don’t have to: spinning up browsers quickly, responsive read/write live view, logs, headless vs. headful mode, replays, residential proxies, and more. Our API allows developers to instantly launch browsers in the cloud, so you can focus on your core product logic rather than the infra underneath. Our customers use Kernel to launch QA agents, vertical-specific agents that automate back office processes, and more. We're open source, HIPAA-compliant (SOC2 Type 2 pending), & compatible with every browser/web agent framework (Playwright, Puppeteer, CUA, Browser Use, Magnitude, etc). Check us out —> https://github.com/onkernel/kernel-images

The world's best AI video generator that turns your documents and/or prompts into whiteboard explainer videos. In addition, we have a similar product that generates podcast-style audio explainers from your documents/prompts. API access available for both video and conversational audio. Product of Red Tree Inc. Please reach out at founders@golpoai.com

VibeFlow generates full-stack web apps from prompts with n8n-style visual workflows for the backend. Users of tools like Lovable or v0 can easily iterate over frontends because they can see them, while backends remain closed black boxes that are hard to evolve through prompting. VibeFlow opens up backend logic, making it visual and editable, with powerful integrations built in.

mcp-use provides open-source dev tools and infrastructure for MCP to help dev teams quickly build and deploy custom AI agents with MCP servers. Our library has over 170,000 downloads and 7,000 stars, and is used by hundreds of engineers at big enterprises. We provide a hosted and self-hosted platform that manages auth, access control, and multi-user environments for secure MCP agents deployment at scale.

You built the demo in a weekend. Now you need auth, a prod-grade database, real-time events, AI observability, cron jobs, email, monitoring… and you needed them yesterday. We spent a decade at our previous startup, building a platform while scaling to millions of users and customers like Meta & Netflix. Now we put that into an open-source framework, so others wouldn’t have to do the same from scratch. Modelence is a batteries-included framework that abstracts away boilerplate so you can just focus on building your product logic and nothing else - it’s like Next.js + Vercel + Supabase on a single platform, built for full-stack TypeScript. Shipping production apps is much harder than building a prototype that runs locally and 95% of all production apps share the same building blocks. We did a massive amount of work on our previous platforms that was not specific to our product, and we’ve created Modelence to abstract that away: - Authentication - Database setup - Hosting / CDN - AI integration (LLM observability, prompts) - Real-time events - Cron jobs - Email service - Monitoring - Analytics - Admin dashboards Andrej Karpathy recently posted about this same exact problem: https://x.com/karpathy/status/1905051558783418370 and explained it further in his YC AI Startup School talk: https://youtu.be/LCEmiRjPEtQ?feature=shared&t=1940

Async is an open-source task management tool that doesn't just track work, it does it. Async automatically triages tickets, completes them, and tests from end-to-end. We're fully open-source and self-hostable, so you can customize Async to work for your company and your processes. Our mission is to kill engineering busywork: bug fixes, UI tweaks, papercuts, and KTLO.

Nottelabs offers a platform to build and deploy enterprise-grade browser agents. We help companies cut costs and save time by automating repetitive tasks. Unlike others, we provide agents, tools, and infrastructure through a single API, making us the fastest path to reliable web AI agents in production.

Alter is a zero-trust identity and access control platform purpose-built for AI agents. It wraps every tool call in strong authentication, fine-grained authorization, and real-time guardrails, so agents can move fast without breaking things. Each request is verified at the parameter level, authorized against granular policies, executed with least-privilege access, and fully audited in real time. Unsafe actions, whether it’s a rogue DROP TABLE or a payment above policy limits, are blocked before they touch production. Behind the scenes, Alter manages credentials, issuing ephemeral, scope-narrowed access for every interaction, then rotating or expiring it in seconds. The result: no long-lived secrets, no blind spots, and no surprises in audit. With Alter, teams can move fast on AI agent initiatives while staying fully compliant with SOC 2, HIPAA, GDPR, and internal security standards. A CISO-ready dashboard delivers real-time visibility, detailed audit logs, and compliance-ready controls, removing silos, eliminating excessive permissions, and providing complete oversight of every agent workflow.

Luminal builds an ML framework and compiler that generates GPU code. Our stack 10x's model speed while simplifying deployment and cutting idle GPU costs Github: https://github.com/luminal-ai/luminal Discord: https://discord.gg/APjuwHAbGy

Embedder is a coding agent that can write, test, and debug firmware on both physical and simulated hardware. Supporting 20+ MCU/SoC platforms, it accelerates embedded systems development across semiconductors, automotive, medical devices, aerospace, IoT, and consumer electronics.

CUDA for phones & consumer hardware: Cactus is used by 3k+ developers and 100+ products to run AI locally on consumer hardware. It is open-source! Check out the repo: https://github.com/cactus-compute/cactus

stagewise builds an open-source frontend coding agent for real codebases. We enable backend devs, designers and product managers to build pretty and functional web apps in a simple and visually guided manner - no matter the used tech stack. stagewise lives right inside your browser, makes changes in your local codebase and is compatible with all kinds of frameworks and setups - allowing it to be retrofitted into any existing project. Our agent enables you to show and tell what you want to change - all while using your app on localhost and without having to switch to external tools. Making changes is as easy as selecting elements, giving a simple prompt like “make it green and put it in the top right corner”, and immediately seeing the result. We're two founders from Germany who met while working at a B2B SaaS startup. With Glenn's background in building dev tools for enterpries (Rheinmetall, Miele), as well as Julians experience in building web apps used by thousands (saasmetrix, strukto.io), we have the unique blend of experience and product sense needed to build this. After making our initial launch with the open-sourced toolbar that puts your favorite coding agent right inside your browser and going viral with it, we’re now launching a high-speed coding agent dedicated to frontend development - taking our product and the experience of our users to the next level. Our vision is to replace frontend devs completely, by gradually enabling both the backend devs, but also less technical designers and product managers to create well-designed applications. We start with developers who lack design experience, but our ultimate goal is to change how products are built.

AgentMail is the email inbox API for AI agents. It gives agents their own email inboxes, like Gmail does for humans.