Developer Tools Startups funded by Y Combinator (YC) 2026

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.

The AI-native observability platform for fast-moving engineering teams. Backed by tastemakers from the world's top AI companies: Vercel, Graphite, Daytona, Browserbase, LangChain, Mastra, Replit, and more.

Teams are shipping faster than ever with AI, but engineers are merging changes that neither they nor their reviewers fully understand, leading to bugs in production and overwhelming cognitive debt. Stage is a new code review platform built for today’s fast moving teams. Instead of forcing readers to piece things together from unorganized diffs, Stage breaks changes down into structured chapters so teams can understand what's happening and ship with confidence.

Runtime (runtm.com) gives engineering teams control and visibility to enable anyone in their org to use coding agents securely. Eng leaders rolling out coding agents have no way to see what's happening, set boundaries, or safely let non-engineers use them. We provide sandboxed environments, session-level observability, and configurable guardrails so anyone on your team can ship with coding agents without breaking prod. We're live with fast-growing YC scaleups empowering their PMs, designers, marketers, and ops to contribute to their codebase or build prod-grade zero-to-one apps.

Manicule is an AI-native technical documentation agency. We own technical documentation end-to-end for developer tool companies, including information architecture, messaging, writing, design, and QA. Agents handle the mechanical parts like code verification and auditing at a scale and speed no human team can match, while humans refine the thinking and make the docs actually good. We're at $15K MRR and profitable, with clients like Supermemory, Greptile, Reducto, and Rootly. Supermemory's docs drove a 30% improvement in answer success rate and went viral on Twitter, all shipped in 23 days. Every dev tool founder knows their docs are broken but simply don't have the time to fix them. The old solution was hiring a full-time technical writer who understands engineering, marketing, and devrel. That role is really hard and expensive to hire for, so docs stay broken. Naman started freelance writing for developer tools 3 years ago and realized that you can't one-shot docs. They require tight feedback loops with the engineering team, multiple review cycles, and real product understanding. When he worked with Supermemory, they had two products that sounded identical to customers. He got on calls with the CEO, figured out the right positioning for each product, and restructured the entire docs around it. That kind of work requires judgment and context that agents simply don’t have. On the other hand, testing every code snippet against a live API, auditing hundreds of pages for broken links, and drafting from OpenAPI specs is grunt work that agents do in minutes. The insight behind Manicule is that good documentation requires both, and nobody has packaged them together. Shreyans was a founding engineer at Supermemory, saw the impact of good docs firsthand, and joined Naman to productize Manicule. We're now a team of 5, building toward that vision. Thousands of AI startups are launching dev tools every month, and docs are the single biggest asset they're all neglecting.

Building the communication infrastructure needed for fully autonomous agents

Glue is an open source design editor for AI agents. It gives coding agents an infinite canvas to create new interfaces, iterate on existing ones, and turn those changes into production-ready code all in real time. The rise of coding agents is collapsing EPD into one role: builders. This new paradigm means design and engineering can now converge to a single workflow. Builders no longer want static mockups in one tool, and implementation in another. Glue is a collaborative workspace where builders and agents can create new components, iterate on existing interfaces, and implement as code. The same tight feedback loop that once made Figma powerful for designers is now built for builders and their armies of agents. Being open source allows us to penetrate workflows at zero cost and build trust quickly. Right now there are no design tools with AI as the primary user. Existing tools bolt on copilots as an afterthought. Soon, every company will have AI agents building their interfaces. We are building the surface for this workflow.

Arga is the infrastructure that lets you validate code changes & agents at scale, because you (and your users) were never meant to be QA for AI. We provide validation infrastructure with fully-functional mocks of external services for your code & agents. Deploy a PR into our production-like sandbox and it runs against replicas of any web app, fully compatible with any official API/SDK. These replicas surface edge cases traditional mocks or assertions miss, and you never hit rate limits. For AI agents, run red-teams with Arga: test tool calls, behaviours, and failure modes before anything reaches production.

AI SRE agents that automatically learn each customer’s system so they work just like an in-house engineer.

Your agent processed a refund without looking up the order ID, costing you thousands. You only found out three hours later from a support ticket. Evals, output scoring, and observability can reduce the likelihood of mistakes like these occurring - but there's no solution that inspects and prevents an action as it’s about to execute. Salus does that. We’ve built an API that wraps around your agent and checks its actions at run time, blocking incorrect ones and providing immediate feedback to guide retries. Kevin and Vedant were roommates at Stanford, where they both studied computer science.

A Coast (containerized host) is a local development runtime. Coasts let you run multiple isolated environments for the same project on one machine. As AI coding agents increasingly work in parallel across git worktrees, developers hit painful conflicts — clashing ports, duplicated databases, and fragile per-branch setup. Coasts solve this by giving each worktree its own fully isolated runtime, so multiple agents can build and test side by side without stepping on each other.

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.

Inspector is the AI IDE for designers to ship to prod. Just select any element on your live front end, edit it like you would in Figma, and Inspector writes the changes straight to your codebase.

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 examines 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.

Understand user patterns and find silent failures in your AI agents. The Context Company helps teams analyze AI agent conversations to surface user behavior patterns, performance trends, and moments where agents struggle - so teams know what’s working, what’s not, and what to improve next. We turn raw conversations into structured signals: topic clustering, user feedback analysis, custom pattern tracking, and alerts. All alongside traditional observability like traces, tool calls, latency, and costs. Get started in 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.

A platform where users can automate web workflows using natural language prompts. We handle deterministic playback of browser workflows and fall back to LLMs where necessary, ensuring reliability.

S2 is an API for durable streams. We make working with streaming data dead simple and reliable. 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.

Specific lets your coding agent write code and build the infrastructure to deploy it. Connect your favorite coding agent and start building immediately. Run `specific dev` to get a full local environment running in seconds. Run `specific deploy` to go to production on our scalable cloud platform in minutes.

1. Multi-model Agents SDK: build production-grade tool-calling agents in 5 lines of code using our open-source, vendor-agnostic SDK. Connect multiple models across providers (eg. Opus 4.6 + Gemini 3 Flash + GPT 5.4) within the same agent to optimize your agentic workflow's cost, latency, efficiency, and performance. 2. Agents-as-a-Service (AaaS): serve your agent or service as a hosted endpoint that anyone - including OpenClaw and Claude Code - can call.

Lark lets teams write end-to-end tests in plain English. Validate dashboards, APIs, SDKs, and full product flows without maintaining fragile test code. Run continuously on feature branches, in CI, or in production.

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.

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).

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.

Omnara brings Claude Code and Codex to your phone. Start a coding session on your desktop, then seamlessly hand off to mobile and keep building whether you're commuting, traveling, or away from your desk. Code in local or remote environments with full context preservation across devices. Plus, use voice to code hands-free by having natural conversations with Omnara to build, debug, and ship from anywhere.

Kernel is crazy fast, open source infra for AI agents to access the internet 🧠🕸️ - Built on unikernels for crazy fast cold starts and low resource usage - Sub-150ms cold starts on managed headful browsers - Built-in stealth mode with residential proxies and automatic CAPTCHA solving - Full observability: session recording, live view, and full logs - Persistent sessions that maintain cookies and auth across invocations - Native support for all browser and computer use frameworks - SOC 2 compliant and HIPAA-ready Trusted by Cash App, Rye, and 1000+ others. Backed by Accel & Y Combinator (S25).

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.

Manufact provides open-source dev tools and infrastructure for MCP to help dev teams quickly build and deploy MCP Servers for AI agents & MCP Apps for ChatGPT and Claude. We developed the mcp-use SDK, which has over 5M downloads and 9,000 GitHub stars, and is used by 20% of the US 500. Create MCP servers/apps in minutes, connect your GitHub repo, and make them immediately available to AI agents and ChatGPT.

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 production ready platform for agentic development that abstracts away boilerplate so you can just focus on building your product logic and deploy it to production without worrying about infrastructure. 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

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.

Check out the project: https://github.com/cactus-compute/cactus

Interfere is the experience layer for modern product teams. Detect, triage, and fix bugs automatically – no human required. Interfere finds issues in your app, understands what's happening, and owns resolution from first signal to production.

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.