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.

Agent Relay helps software teams work better with coding agents, and helps those agents work better as a team. It gives Claude Code, Codex, OpenCode, and custom agents shared messaging, session history, and access to tools like GitHub, Linear, and Slack. Teams can see what every agent is doing, run checked and resumable workflows, and step in when human judgment is needed. Run it in our cloud, locally, or on your own hardware.

* Ready to Use Instantly: Skip the complex server setup. It comes pre loaded with top AI Agents (like Claude Code and Hermes) so your agents can start working immediately. * Keep Your Work Safe: Unlike other systems that delete everything when they finish a task, these sandboxes remember your files, code, and settings forever until you delete them. * Pay Only for What You Use: Stop paying for idle servers. You pay a tiny fee to store your files, but you only pay for compute power during the exact minutes your AI is actively running. * Zero Infrastructure Headaches: You don’t need to be a senior DevOps engineer or manage complex cloud networks. One simple command handles the entire backend for you. * Connect to Any App: Allow your AI agents to securely log into and interact with everyday tools like Slack, Gmail, and GitHub in just a few clicks.

Mirrors provides regression testing for AI agents. Teams shipping agents constantly change prompts, models, and tools, and there's no way to test any of it. Agents call bespoke internal tools and APIs no test framework can reproduce, so most teams ship on vibes. Mirrors rebuilds the tools your agent calls from your own production traces, then replays real sessions against every change before it merges. You see which tool calls changed, which arguments moved, and where state landed differently. And when something fails, we tell you whether your agent regressed or something upstream moved. Built for teams whose agents take irreversible actions. Refunds, record updates, outbound email. Runs in your CI on every PR.

ByteAsk is an AI coding agent built for C and C++, the code that runs trading systems, cars, chips, and operating systems. It does not stop at a diff that looks right. ByteAsk builds, debugs, and tests every change with the real toolchain until the change holds. If the compiler, the debugger, or the tests can catch it, then ByteAsk catches it too. It runs from the terminal or inside VS Code, Neovim, and Emacs, and is available fully on-prem.

Maritime is cloud infrastructure for AI agents. We help companies give every customer an agent running in its own isolated, persistent computer, starting at $1 per agent per month. Maritime handles hosting, scaling, and sleep/wake automatically, so developers can run thousands of agents without managing the infrastructure.

**Problem** Humans used to need laptops to do their work. Now they prompt agents instead, and those agents need computers too: always-on, in large quantities, and with unlimited capabilities. Building and maintaining that yourself is far from trivial. **Solution** Boat provides powerful, simple, permissive Ubuntu VMs in the cloud. In a sandbox, an agent can work for long periods on code or on knowledge work like legal, research, reporting, and auditing. **Why Boat and not any other cloud VM?** 1. It is ready out of the box: every sandbox ships with a desktop, chrome, languages, docker, snapshots, and templates, plus a CLI, SDK, API, and control pane for your fleet. 2. It is permissive and paradigm agnostic: any number of agents can use any number of sandboxes. Agents can run inside or use sandboxes as an external tool. 3. It is expertly crafted: we manage everything from the individual CPU to the orchestration software, which makes sandboxes stable, persistent, scalable, and secure. 4. It is the best performance and price in town: our CPUs rank first on HPC benchmarks, and sandboxes are typically 9x to 18x cheaper than other leading sandboxes. **Further notes** Sandboxes are hosted in Europe, which keeps prices low, and more regions are coming. Unless compliance requires it, agents don't notice the region they run in.

Workers IO verifies your entire system across millions of interleaving, faults, and timings to find the exact conditions that break the software properties you care about. Built for teams where 99.99% uptime is table-stakes.

We build physical agent harnesses to enable AI to debug, validate, and ship functional hardware and software.

Mentlio an applied research lab focused on optimizing AI ROI for the modern enterprise. We help engineering teams draw a line between their AI spend and delivery, per engineer. We then cut ~30% of AI spend via Mentlio's custom ML-based intelligent routing, context optimization, and prompt compression.

Developers don't run one coding agent anymore. They run fleets of them — for hours, sometimes days — across laptops, servers, and sandboxes. Keeping track of that work is the new bottleneck: which agent is blocked, which one finished, which terminal is it in, and why did everything die when the laptop closed. Herdr is the open-source home for that work. A background server owns the agents' terminal sessions on each machine, so the work survives disconnects, closed lids, and dropped SSH. Herdr detects each agent and turns the chaos into an attention queue — working, blocked, done, across every project — so you look only when an agent needs you. Every client is just a view: the bundled terminal UI, SSH from another machine, your phone. Close one, open another; the work never stops. Software can drive it too: a CLI, a socket API, and a plugin marketplace that passed 500 community plugins in its first month. The runtime is Apache-2.0 and stays open. Four months after launch: 25k GitHub stars, 340k downloads.

An agent is LLM + harness: We work purely on that second component. We do research and engineering to produce the most capable and efficient harness. Our harness has 20k stars on , and has $1m/month of inference spend

Agent FM is a desktop app that gives engineers one group chat to hear and steer their coding agents. Instead of manually bouncing between different claude code and codex sessions, and combing through walls of text to monitor agents, engineers just tune in to Agent FM. Agents share important progress updates, blockers, assumptions, and decisions in the group chat. Engineers get live text and audio updates and respond right from the chat.

Intelligence will be the most valuable asset a company owns. Today, almost every company rents it. Companies pay a handful of labs one token at a time. Each dollar buys an answer, not an asset. They spend more, but own nothing more. Riften reverses that. Change one environment variable and Riften becomes the gateway for a company's AI traffic. We route each request to the lowest-cost model that can do the job, serving most work on open-weight models we host. Customers save money immediately without rebuilding their products. The gateway is the entry point. Over time, Riften turns the company's work into private models built on open weights and shaped around the business. What begins as cheaper inference becomes an intelligence stack the company owns, runs on infrastructure it controls, and uses to power its most important applications. We call this earned intelligence. It is created by the company's own work, controlled by the company, and accumulated over time. The next generation of companies will not rent their intelligence. They will earn it, own it, and compound it. Riften is how they get there.

hiloop helps teams train agents for tasks where general models are not good enough. Give us a task, your current agent or model, and an evaluation. hiloop runs an autoresearch campaign across data, SFT and other post-training methods, continual learning, prompts, tools, harnesses, and systems, then returns the best verified improvement. It runs hosted or in your cloud. We provide the research system around models: persistent memory, full experiment lineage, compute orchestration, and statistical verification. We’re starting with agent and model training, continual learning, and optimization. Reach out to us for early access at founders@hiloop.ai.

We build GitHub for agents. We're rebuilding the infrastructure for the next hundred billion commits and CI jobs with hundreds of engineers already making the move.

Graphify is a Knowledge Graph control plane for enterprise software. The open-source tool has 116K+ GitHub stars and 6.5M+ downloads, and is used in production by engineers at Shopify, Datadog, JP Morgan, American Express, Harvey, Automation Anywhere, and Vanguard. On top of that graph, our enterprise layer reviews every pull request and formally verifies each code change: it proves the new behavior matches the old, or hands back the exact input that breaks it. That makes it built for the changes teams fear most, like refactors, framework upgrades, and large-scale migrations, where you need proof that nothing broke, not a guess. The graph updates itself as the code changes and keeps context instead of forgetting it, so your whole team and their coding agents work from one shared, always-current view of the codebase instead of a thousand private threads. It runs entirely inside your perimeter, fully air-gapped on-premise or self-hosted in your own cloud, so no code or data ever leaves your environment.

Agency Tool Company ships software to robots in the field 20x faster than a Docker pull with ATC Deploy, sending only the bytes that changed and resuming when the network drops. Deployment tooling is the connection between the lab & the field that continually bottlenecks robotics scaling and lacks a strong robotics-native solution. Deploy is live today with 3 launch partners across ag, construction, and logistics robotics. Our second product, ATC Build, offers embedded-compute as a CI service so devs can run tests and validate their software on the actual target hardware. Build supports the Nvidia Jetson lineup, Raspberry Pi, and a number of other embedded platform targets. Jack Morrison and Davis Foster founded and sold Scythe Robotics after deploying hundreds of autonomous mowers across the country; Agency Tool Company is building the robotics deployment platform across hardware and software they wish they had. Learn more at https://agencytool.com

Hardware Intelligence makes chip design tools that cut simulation and debugging time by an order of magnitude. When a chip test fails, engineers need a recording of every internal signal - a waveform. We’ve developed WaveZip, which captures waveforms 500x smaller with 200x less overhead, and Wave, which beats frontier models on industry chip debugging benchmarks. We’re Rishov Sarkar (Georgia Tech Ph.D. in chip simulation) and Athreya Anand (ex-Google, M.S. ML/AI), YC S26. https://hardwareintelligence.ai

Alkera is a data engineering/analysis/science agent that works in your IDE or CLI. If you’re tired of agents that produce false, or even dangerous, reports about your data, then Alkera is for you. Our agent is equipped with your data’s history and lineage, your team’s knowledge, and tailored plugins for data apps such as Snowflake and dbt. Simply install and connect your services to begin doing trusted agentic data work. We also offer VPC & on-prem deployment options for when data can't leave your boundary.

There are thousands of models, providers, and harnesses, each with its own pricing and strengths, leaving an overwhelming number of choices when it comes to managing token spend and intelligence. Conifer uses intelligent routing and orchestration logic to handle the full path of each query: model selection, provider choice, and cache management. It all runs inside your existing harness, so tools like Claude Code and Codex work without changing your setup. By centralizing where inference occurs, Conifer lets companies save on their inference bill while leaving teams free to focus on what they are building.

Agnost AI reads every conversation a company's AI Agent has with its users to find where it's silently failing and then turns that same data into custom models that run the agent better, faster & cheaper than frontier models.

With tools like Cursor and Claude Code, writing software is no longer the bottleneck. Debugging is. Agents cannot fix production crashes using logs and traces that were sized for human eyeballs. The gap is missing data. HyperProbe allows agents to debug live software autonomously. Our SDK drops non-breaking probes straight into running services to read exact variable states from memory at the moment of failure, instead of reasoning backwards from flat logs. Zero redeploys. Under 1% CPU overhead. Automatic PII redaction. We turn 4-hour production war rooms into 10-minute automated resolutions. As agents write and operate more of the world's software, HyperProbe is the runtime observability layer that lets them understand what they built.

We build Maxxwell, a desktop app for people who run several coding agents at once. Past two or three sessions, you become the bottleneck. Every session asks you something, most of it small, and you spend the day answering instead of deciding. It is also hard to tell which sessions are making progress, which are stuck on something trivial, and which have quietly started building the wrong thing. Maxxwell puts every session in one window and marks each one working, idle, or waiting on you. On top of that sits an orchestrator, a real coding-agent session of its own that reads the others and reports back. You talk to it instead of to twelve terminals. It tells you what landed, what it decided for you, and what actually needs your call. Every worker is your own tool, unmodified. Claude Code, Codex and Cursor Agent run in real terminal sessions you can attach to and take over at any point

Speko is a router for voice models: one API key, and your voice agent runs on the speech-to-text, LLM, and text-to-speech models we measured as best for your language and use case. The measurements are public at benchmarks.speko.ai: we test new models the day they ship and re-route when the numbers change, so you rewrite nothing. We ran this bake-off by hand for four years at previous company, shipping production voice for Fortune 500s.

For your AI agents to behave like teammates, we give them persistent identities with their own email, phone, and iMessage. We also provide them an agent-to-agent channel, so they can communicate for task delegation.

Prized is a cloud development environment that feels local on your Mac. Developers get a dedicated, persistent machine with their repos, dependencies, and tools already configured. Files sync into a real local folder, remote ports appear on localhost, and terminals persist through tmux, so developers and coding agents can keep working even after the laptop closes. Machines can be resized or cloned as workloads grow, without rebuilding the development environment.

Simantic is modernizing the embedded firmware industry with hardware simulation developed for the adoption of AI in hardware engineering. Simantic gives both humans and AI the visibility into hardware previously limited by the physical world.

Linzumi is the chat your engineering team uses to direct dozens of AI coding agents. Kick off work, review it, ship it. All from chat. See every agent's work. Unblock the agents that need you from your laptop, your phone, the coffee line. Your teammates see it too. Every decision your team makes compiles into a source of truth - what to build, why it changed, how your agents should act. That same source generates new work and verifies completed work. Deliberative alignment, repurposed from aligning LLMs to aligning companies.

machine0 is a CLI for agent compute: `machine0 new mybox` gives your agent a full cloud VM, billed by the minute, from small up to 60 vCPU / 240 GB and 8×H100s. Agents drive it themselves via CLI or MCP. Agent workloads are moving from ephemeral to always-on. A coding agent working on a hard feature runs 6-8 hours. Auto-research agents run for days. machine0 is the environment in which these agents run.

Zenbu is an extensible IDE for orchestrating coding agents. Shape it around exactly how you and your team work.

Codag compresses tool call outputs before agents read them, which reduces token spend by 20-30% while retaining output accuracy. Govern and see analytics on agent dollars across all model providers and internal agents.

Archal provisions sandboxes with the API environments your CI, tests, and evals need. Your coding agent can start the sandbox & environments, connect to your API integrations, run tests, and inspect state changes. Sandboxes and environments are startable within seconds and take milliseconds to reset.

Inth monitors your pull requests, codebase and website to catch privacy issues and turns them into fixes and evidence. Every product change you make exposes you to privacy risk. Customers lose trust. Fines and lawsuits are given. Fundraising and customer deals are broken. New market launches halt. The growth you thought you would have slows because privacy compliance is overwhelming and changes with every product update. Inth is fixing this to help you automate privacy compliance to ship and grow faster. Inth scans your PRs, website and codebase to catch any privacy risk. It then fixes and evidences them against your product, policies and global privacy laws to automate privacy compliance in every region your customers are in. Start a free privacy scan at: inth.com

Sentry and Datadog dump a stream of alerts. Most are duplicates, most lack context, and you still have to solve the issue yourself. Superlog is AI-native observability that's meant not to be opened. A wizard scans your repo and installs proper OpenTelemetry instrumentation, then runs daily to keep up as you ship new code. When something breaks, Superlog groups the errors into a single incident, investigates with full context (logs, traces, recent deploys, past Slack threads), and posts one mergeable PR in Slack. You merge it, ignore it, or open it as a Claude Code session and modify it. Telemetry is vendor-neutral, so you keep every log, trace, and metric we install, even if you leave.

Billions of machines are left untouched by agents and work individually. We connect them to unlock multiplayer cloud coding agents for work like engineering, math and research.

We build human foundation models. Our first family of models powers lifelike avatars that interact with users in real time, enabling AI agents and applications to go beyond text and voice with just a few lines of code. State-of-the-art realism with ultra-low latency at scale.

Replicas is a cloud coding agent that allows you to delegate tasks to Claude Code or Codex from the app, Slack, Linear, and more. Each task works inside of a sandboxed virtual machine, allowing teams to heavily parallelize work and burn through tickets. Replicas agents output higher quality PRs via feedback loops - each task automatically is notified and fixes CI failures and reads all code reviews. With Environments, engineering teams can configure agents to run their entire codebase locally, verify its work, and provide preview URLs.

Superset is an open-source IDE that helps engineers run 100s of coding agents in parallel. Our desktop app is loved by tens of thousands of engineers, and we're scaling out our effort to build a collaborative, cross-platform tool to allow users to code anywhere.

You should only be paying frontier model prices for top-shelf reasoning. But 88% of your token bill is just tool I/O. Quotient Labs runs on top of Claude Code to reduce token spend, compress context, and optimize tool calls while preserving output quality. Same models, same workflow, no changes to how you work. Benchmarked 47% less cost on real, multi-step developer workflows, with no quality loss.

/dev/fast is the AI-native code forge. We're building 'Review', an open-source Cursor for code review. The Review app is designed to give you confidence in your code. Critique interactive visualizations, diffs, and agent traces, all from one interface. Learn more at https://dev.fast

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.

Corelayer is the AI-native platform for production software support, built for regulated industries like finance and healthcare. It continuously monitors alerts, logs, infrastructure, and underlying data for issues and uses agents to debug and suggest fixes. We're helping SRE, production services, and on-call engineers at companies ranging from growth-stage fintechs to Fortune 500 financial institutions spend less time on support and more on high-leverage work.

Skillsync gives you one place for everything your agents have ever done, and makes all of it portable. Move a full session between Claude Code, Cursor, Codex, and any other agent with nothing lost, including the entire conversation, the model's reasoning, and every tool call, not just a summary, so the next agent picks up like it was there the whole time. Because your sessions are portable, they stack up instead of disappearing. Every past session stays searchable and feeds your next agent automatically, so you never re-explain yourself or redo work you have already done. Everything stays on your machine and nothing leaves unless you choose to send it. Skillsync is local-first and yours, and its core engine, txcript, is open source, a portable session format that no single provider owns.