B2B Software and Services Startups funded by Y Combinator (YC) in San Francisco 2026

Deel is the all-in-one payroll and HR platform for global teams. Built for the way the world works today, Deel combines HRIS, payroll, compliance, benefits, performance, and equipment management into one seamless platform. With AI-powered tools and a fully owned payroll infrastructure, Deel supports every worker type in 120+ countries—helping businesses scale smarter, faster, and more compliantly. Discover how Deel makes global work simple at deel.com.

Faire is an innovative online marketplace that uses machine learning to match local retailers with the brands and products that uniquely fit their stores. We are using the power of technology to connect brands and independent retailers from all over the world, building a thriving community of hundreds of thousands of retailers, which has resulted in over 7 million new connections to date. Faire was founded on the belief that the future of retail is local. Our mission is to empower brands and retailers to strengthen the unique character of local communities. Our data-driven approach unburdens retailers from decades-old obstacles by helping find the right products for their shop. Plus, our straight-forward financial terms level the playing field by eliminating inventory risk and providing access to capital—key offerings previously only available to big box chains. For brands, our platform provides powerful sales, marketing, and analytics tools that simplify their business and allow them to focus on what they love: making great products.

Rippling gives businesses one place to run HR, IT, and Finance. It brings together all of the workforce systems that are normally scattered across a company, like payroll, expenses, benefits, and computers. For the first time ever, you can manage and automate every part of the employee lifecycle in a single system. Take onboarding, for example. With Rippling, you can hire a new employee anywhere in the world and set up their payroll, corporate card, computer, benefits, and even third-party apps like Slack and Microsoft 365—all within 90 seconds. Based in San Francisco, CA, Rippling has raised $1.2B from the world’s top investors—including Kleiner Perkins, Founders Fund, Sequoia, Greenoaks and Bedrock.

Scale accelerates the development of AI within organizations of any size to deliver critical business insights and operational efficiency. Its data-centric infrastructure platform leverages RLHF (Reinforced Learning with Human Feedback) to help organizations build the strongest AI models that supercharge their business, with customers across industries including Meta, Microsoft, U.S. Army, DoD’s Defense Innovation Unit, Open AI, General Motors, Toyota Research Institute, Brex, Instacart and Flexport.

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.

GrubMarket is the AI-powered technology enabler and digital transformer of American Food Supply Chain industry. Our mission is to build and provide the eCommerce and software technologies to this industry, to transform this completely offline and highly manual industry into modernized online industry powered by software technologies, and improve the efficiency of American food supply chain.

Checkr builds people infrastructure for the future of work. And we believe everyone should have a fair chance to work. That's why we've designed a faster—and fairer—way to screen job seekers. For more information on our mission and products, visit https://checkr.com.

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

Founded in 2013, we believe trade can move the human race forward. That’s why our mission at Flexport is to make global trade easy for everyone. What the internet has done for bits and bytes, Flexport is doing for physical goods: giving every business the ability to connect to any customer, wherever they are in the world. That sounds pretty straightforward, but a fragmented and inefficient global supply chain has held the world back from untapped growth and innovation. By connecting everyone in the global economy we can unlock commerce, creativity, and human progress. To do so, we’re building the platform for global logistics—empowering buyers, sellers and their logistics partners with the technology and services they need to grow and innovate. Today, we work with more than 40,000 customers and their suppliers across industries like manufacturing, retail, electronics, consumer goods, tech, apparel, and beauty. Companies of all sizes—from emerging brands to Fortune 500s—used Flexport technology to move nearly $19B of merchandise across 112 countries in 2021. Interested in joining our team? Check out our open job postings on careers site and apply directly today! https://www.flexport.com/careers/jobs/

Webflow is the leading no-code visual web development platform. It seamlessly generates sophisticated code so anyone can build powerful web-based businesses and adapt to changes without developers or months of building. From entrepreneurs and creative agencies to Fortune 500 companies, Webflow makes the internet a more inclusive place by making the tools to build on it more accessible to more people, fueling business growth. Webflow powers websites for innovators like Discord, Monday.com, IDEO, Orange Theory Fitness, TED, and Dropbox. Webflow is backed by Y Combinator, Accel, CapitalG, Silversmith, and other awesome investors.

Fivetran automates data movement out of, into and across cloud data platforms. We automate the most time-consuming parts of the ELT process from extracts to schema drift handling to transformations, so data engineers can focus on higher-impact projects with total pipeline peace of mind. With 99.9% uptime and self-healing pipelines, Fivetran enables hundreds of leading brands across the globe, including Autodesk, Conagra Brands, JetBlue, Lionsgate, Morgan Stanley, and Ziff Davis, to accelerate data-driven decisions and drive business growth. Fivetran is headquartered in Oakland, California, with offices around the world. 

Biotechnology is rewriting life as we know it, from the medicines we take, to the crops we grow, the materials we wear, and the household goods that we rely on every day. Biotech R&D is radically transforming our world, but to move at the new speed of science, scientists need better technology. Benchling’s mission is to unlock the power of biotechnology. The world’s biotech leaders and innovators use our R&D Cloud to power the development of breakthrough products and accelerate time to milestone and market.

Founded in 2011, Zapier is the #1 workflow automation platform for small and mid-sized businesses. By connecting more than 6,000 of the most popular work apps, Zapier empowers its users to make the most of the tools they already use—and to focus on what matters most.

Dropbox is building the world’s first smart workspace. Back in 2007, making work better for people meant designing a simpler way to keep files in sync. Today, it means designing products that reduce busywork so you can focus on the work that matters. Most “productivity tools” get in your way. They constantly ping, distract, and disrupt your team’s flow, so you spend your days switching between apps and tracking down feedback. It’s busywork, not the meaningful stuff. We want to change this. We believe there’s a more enlightened way to work. Dropbox helps people be organized, stay focused, and get in sync with their teams.

Mixpanel is analytics for builders that need answers from their data at their fingertips. When everyone in the organization can see — and learn from — the impact of their work, they are poised to make better decisions. Companies like OpenAI, Netflix, Pinterest, sweetgreen, CNN, samsara, Uber, and Yelp use Mixpanel to understand their customers, measure progress, and endeavor to make better decisions.

PagerDuty is an operations performance platform delivering visibility and actionable intelligence across the entire incident lifecycle. Their SaaS-based solution empowers over 10,000 small, mid-size and enterprise global customers such as Comcast, eHarmony, Slack and Lululemon with the insight to intelligently respond to critical disruptions for exceptional customer experience. PagerDuty was founded to deliver a new and innovative approach to increase business response and efficiency. When brand reputation depends on customer satisfaction, PagerDuty arms businesses with the insight to proactively manage incidents and events that may impact customers across their IT environment.

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.

Launched in 2012 as ZenPayroll, Gusto serves more than 300,000 businesses nationwide. Each year we process tens of billions of dollars of payroll and provide employee benefits—like health insurance and 401(k) accounts—while helping companies create incredible work places. Through one refreshingly easy, integrated platform, we automate and simplify your payroll, benefits, and HR, all while providing expert support. You and your employees will get the peace of mind you need to do your best work.

At Optimizely, we're on a mission to help people unlock their digital potential. We do that by reinventing how marketing and product teams work to create and optimize digital experiences across all channels. With Optimizely One, our industry-first operating system for marketers, we offer teams flexibility and choice to build their stack their way with our fully SaaS, fully decoupled, and highly composable solution. We help companies around the world orchestrate their entire content lifecycle, monetize every digital experience and experiment across all customer touchpoints – all through Optimizely One, the leading digital experience platform that powers every phase of the marketing lifecycle through a single, AI-accelerated workflow. Optimizely has nearly 1500 employees across our 21 global offices and has 700+ partners. We are proud to help more than 10,000 businesses, including H&M, PayPal, Zoom, and Toyota, enrich their customer lifetime value, increase revenue and grow their brands. At Optimizely, we live each day with a simple philosophy: large enough to serve, small enough to care. Learn more at optimizely.com.

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.

Applied Kinetics builds and deploys specialized AI employees to handle the coordination work behind America's energy and data center buildout. Our agents chase suppliers, track equipment approvals and delivery dates, and flag delays so project teams can keep critical equipment moving without hunting for updates across emails and spreadsheets.

AI made software engineers 100x more productive. We're bringing that same transformation to knowledge workers with the AI desktop.

Like ChatGPT or Claude, but it runs in the cloud, remembers everything you give it, and comes loaded with skills. Hand it a job tonight and read the answer in the morning. Use it on your own, or with your whole team.

Papaya is the optimization engine for AI agents. Engineers don't have time to continually improve the agents they've shipped — the context bloat, overly chatty subagents, and broken tool calls sit in production traces nobody reads, quietly hurting agent efficiency. With Papaya they connect their agent directly via SDK, get actionable recommendations on how to improve quality, latency, and cost, and the ones they approve are pushed to production as pull requests. Papaya runs 200+ research-backed analyses across context, prompts, prompt caching, subagents, and tool calls. Every recommendation is ranked by impact and comes with the production runs that produced it — typically a 10%+ quality improvement on the first workflow analysis.

we build self-healing browser infrastructure that runs millions of agent operations a day without supervision. teams use it for large-scale data collection, agentic workflows, continuous monitoring, and anything else that requires acting on the web at volume.

DeepMark is the authentication layer for AI voice. When an AI agent speaks, we embed a compact, machine-readable ID directly into the audio, not in metadata, which gets stripped the moment a file is touched. The ID resolves to a trust record, so a bank, a call center, or the person on the line can verify in real time who the agent is.

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.

Sona8 is a voice agent that talks to every employee about how their work gets done. Consulting, transformation and corporate development teams spend a large part of every project on stakeholder interviews and stakeholder alignment, and still only hear from a small share of the people affected. Each employee gets a link and talks to the agent for about 20 minutes. The agent asks follow-up questions, for example why a step is still done by hand or who else is involved. From the conversations we build process maps and a list of the problems people described, by site and team. During the implementation, the agent goes back to the employees involved after each initiative and asks whether it was implemented and what changed. The result is a project management office that has talked to every employee. Today consulting firms buy it for the stakeholder interviews at the start of an engagement. Transformation and corporate development teams buy it to run the implementation of a change program. Over time this becomes the way a company knows how it runs. Sona8 reads the systems the company already uses, connects them to what employees said, and keeps the picture current by asking again. Before a decision, you ask what it would do across sites and teams and get an answer from the whole company. A small team steers a company-wide program that used to need a large one. And AI agents inside the company come here first to learn how the work is done before they change anything.

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.

Build agents that research accounts, find prospects, run campaigns, update your CRM, qualify inbound, and more. Connect them to the systems you already use and let them work alongside your GTM team. Engineer your revenue factory on Frontrunner.

We design and collect audio datasets for training speech models.

Hopper post-trains STT, TTS, and speech LLMs on your production calls, then serves and improves them against your live traffic

OnePatch is a forward-deployed AI SRE. It instruments your services, watches how they actually behave in prod, catches incidents, and drives each one to resolution. Think Datadog, except it doesn't stop at telling you something broke: it keeps going until the fix is shipped.

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.

Intelligent Cloud for AI workloads

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.

Nobody's built truly proactive AI, because it requires running inference on your entire life. In the cloud, that's insanely expensive and a privacy nightmare. But not on your own chip. Every night, Sentient's on-device LLM wakes your Mac and understands what's new in your life (email, messages, files, Granola transcripts...), entirely locally, and distills it into a knowledge base. You wake up to your work already prepared: the reply you forgot, drafted from your own context; the subscription you never use renewing tomorrow, caught; the report you promised in the group chat, ready to send. Everything is one click from firing through computer use, and nothing fires until you click. Or click your Mac notch anytime and say "finish this for me." Sidekick takes over the thing you were doing with its own cursor while you move on. On-device inference at this scale was supposed to be impossible: devices too slow, and models too dumb. So we built the stack ourselves: a custom LiteRT-LM fork (KV-cache reuse, speculative decoding, custom k-quants) that runs nightly on 8 GB Macs. The user's hardware does ~90% of the compute, and their own ChatGPT or Claude subscription does the rest, so our marginal cost is ~$0, and our servers store nothing. We soft-launched late July with one Reddit post: top of r/macapps, 2,000+ users in 48 hours, $0 marketing. Free and open source for consumers; the same engine on the work stack (Slack, Granola, Linear, Notion) becomes the enterprise business. Sentient OS raised ~$1M in pre-seed, backed by YC, Afore, and the a16z Speedrun scout fund.

Studio is a simulation lab studying how humans and societies respond to new ideas, and is building the first software models that can accurately predict that response. Instead of creating digital twins of survey respondents, Studio builds live market models of interconnected audience segments from real, traceable consumer-behavior data. Our simulations match live KPI outcomes like revenue and purchase behavior with over 97% accuracy for consumer-facing enterprises, higher than any synthetic panel, simulation lab, or traditional market research.

OpenTag is an AI coworker in your Slack with full context on your company. It answers questions and takes real work off your plate. It also keeps your wiki up to date automatically, so knowledge never goes stale.

Lantern learns what exceptional looks like for your team, pressure-tests the role against the real talent market, then runs the hiring loop: sourcing, inbound applications, interviews, assessments, candidate communication, and offers.

Callbook AI is a collections agency operated by AI. We collect late stage portfolios by finding, contacting and negotiating with borrowers.

Marker is a platform for rebuilding enterprises agent-first, delivered by forward-deployed engineers. It productizes every step from discovery to production, so every agent we ship makes the next one faster.

Lightfield connects to a company’s email, chat, and business systems and does the legal work before it reaches the legal team. It gathers context, applies company policies and past decisions, and presents the completed work to in-house counsel for approval.

Lyon builds private foundation models for banks, insurance companies, and fintechs. Each model learns from the company’s proprietary transactions, payments, clicks, and customer interactions to predict credit, fraud, collections, income, churn, and lifetime value; and runs inside the company’s cloud, so its data and intelligence remain under its control. Lyon is already working with a major insurer and trained a model on 28B transactions for a fintech serving tens of millions of active users, identifying premium-card converters 4x more precisely than its existing rules; the model is now being deployed for credit.

Dream makes AI cameras that catch damage teams miss. Car dealerships, equipment rental companies, fleets, and more move expensive assets in and out all day, and undocumented damage is a costly leak. Dream cameras are simple to set up and work automatically. Each vehicle or machine that passes is photographed from every angle, identified, and reconstructed into a complete condition record. On return or intake, Dream instantly flags new dents, scrapes, and changes your team might miss, giving one source of truth for every asset's condition over time. Ryland worked at X/xAI and built aerial damage-detection vision at Vexcel Imaging. Alexander worked at AWS and trained edge-camera models deployed in the wild across Africa and India to detect poachers.