API AI Startup Jobs

API-first stock/ETF/crypto brokerage infrastructure for developers.

Enterprise voice AI platform offering Speech-to-Text, Text-to-Speech, and Voice Agent APIs for real-time and batch use, deployable in cloud or self-hosted.

ElevenLabs is the leading AI voice technology platform, offering ultra-realistic text-to-speech, voice cloning, and audio AI tools used by content creators, enterprises, and developers worldwide. The company has grown to over $330M in annual recurring revenue and serves customers across 45+ countries including Deutsche Telekom and Revolut.

Stainless generates best-in-class SDKs from API specifications, serving customers including OpenAI, Anthropic, and Meta.

april is an embedded tax infrastructure platform that lets financial services partners offer fast, accurate tax filing and year-round tax advisory services through API integration. Serving wealth management firms, banks, gig platforms, and SMBs, april became the first new company in over 15 years to achieve national e-file coverage.

Runlayer is the enterprise control plane for Model Context Protocol (MCP), providing security, observability, and management that lets organizations safely connect AI agents to their internal systems. Backed by customers including Gusto, Instacart, and Opendoor, the platform combines threat detection, detailed permissions, and enterprise development capabilities in one solution.

Mercury is a fintech company providing a full-stack banking platform built specifically for startups and scaling businesses. With products spanning checking, savings, treasury management, corporate cards, and venture debt, Mercury serves over 200,000 startups.

Infinite canvas SDK for React enabling developers to build web-based whiteboards and collaborative visual experiences, powering products like ClickUp Whiteboards and Padlet Sandboxes.

Health insurance data platform modernizing benefits data exchange between HR tech and carriers.

Messaging and chat API/SDK platform for scalable in-app communication.

Codex is building a stablecoin-native blockchain designed specifically for cross-border payments and FX, providing on-ramps, off-ramps, and fiat-to-fiat transfers with built-in compliance and identity systems. The platform operates on an Ethereum Layer 2 using Optimism's tech stack, targeting payment service providers and enterprises in emerging markets.

dottxt builds structured generation tooling for production LLM applications, helping developers force reliable outputs that plug into existing software systems.

1Money is building the world's first Layer 1 blockchain protocol designed exclusively for stablecoin payments. Founded by former Binance.US CEO Brian Shroder, the network targets enterprise-grade payment use cases with the fastest and most compliant infrastructure.

Market-leading SaaS platform helping governments worldwide automate building permitting, inspection, licensing, planning, and community development with enterprise-grade cloud solutions.

Adaptive builds AI-native finance tooling to automate accounting and operations workflows for modern software and startup teams.

Adaptive Computer builds AI agents that act as a personal and business computer for automating day-to-day work.

AI platform providing reinforcement learning operations (RLOps) tools that enable organizations to customize, evaluate, and serve specialized large language models for production use cases. Founded by key contributors to the Falcon and BLOOM open-source LLM projects.

Adopt AI builds an agentic automation platform for software and operations teams, giving applications and internal workflows AI agents that can execute across existing tools, connectors, and business processes.

Alice & Bob is a Paris-based quantum computing startup building the first universal, fault-tolerant quantum computer using cat qubits with built-in error correction. The company has developed a roadmap to 100 logical qubits by 2030.

Allium is an enterprise-grade blockchain data platform that provides accurate, fast, and simple blockchain data across 100+ blockchains and 1000s of schemas, delivering historical and real-time data through interactive dashboards, APIs, and custom integrations for institutions and crypto enterprises.

Alloy Automation provides an embedded integrations platform that enables product and engineering teams to build, deploy, and manage SaaS integrations. The platform offers low-code integration builders and connectivity APIs for B2B software companies.

Amberflo is an AI monetization infrastructure platform that enables companies to track usage precisely through unified metering, cost attribution, and billing automation. Built for the AI and agentic era, it provides centralized FinOps, credits management, and revenue recognition capabilities for teams deploying LLM-based products.

Amenitiz offers an all-in-one hotel management platform for independent hoteliers, including booking, payments, and operations tools.

Anvil provides a document SDK that helps product teams automate paperwork workflows including PDF generation, form filling, data extraction, and e-signatures. The platform enables developers to build document automation directly into their applications.

Anyscale provides a fully-managed compute platform built on Ray, an open-source distributed computing framework originally developed at UC Berkeley. The company enables developers to build, deploy, and scale AI and Python applications without requiring deep infrastructure expertise.

AppBrilliance offers a patented Money API that enables real-time, non-custodial payments through FedNow® and RTP®.

Arcade AI is an MCP runtime platform that enables AI agents to take secure, authenticated actions across business systems. The platform provides agent-optimized tool calling, OAuth-based authorization, and governance infrastructure for production AI deployments.

Array is an embedded fintech products platform that helps digital brands, financial institutions, and fintechs bring consumer financial products to market quickly. The platform provides tools for credit monitoring, identity verification, and financial wellness features.

AssemblyAI develops speech AI APIs and voice models for transcription, speech understanding, and developer workflows that turn audio into structured application data.

Astrada is the data layer for autonomous finance, providing real-time card transaction data infrastructure that unifies financial data across fragmented enterprise systems. It connects directly to card networks to deliver structured, real-time transaction data via API, enabling AI-powered forecasting and autonomous finance operations for spend management platforms. Customers include Workday, Zoho, Payhawk, Miter, and Extend.

Attio is an AI-native CRM platform built for go-to-market teams. It combines flexible data modeling, real-time collaboration, and AI-powered workflows to help companies manage customer relationships and pipelines. Backed by GV, Redpoint, and Balderton, it serves over 5,000 customers including leading AI companies.

BaseHub is an AI-native headless CMS for developers, letting teams model content, expose it through structured APIs, and integrate AI-assisted content workflows into web products.

Life insurance technology platform helping carriers digitize products and distribution.

Better Auth builds an authentication framework for TypeScript teams, combining open source auth primitives with managed infrastructure for sessions, identity, fraud controls, and user management.

Bird (formerly MessageBird) is an AI-powered cloud communications platform that enables enterprises to connect with customers globally through email, SMS, WhatsApp, and other messaging channels at scale with 99.3% delivery rates. The platform powers 40% of global commerce email.

Black Forest Labs is a generative AI company that created FLUX, one of the most advanced open-source image generation models, and previously pioneered Latent Diffusion and Stable Diffusion. Founded by machine learning researchers Robin Rombach, Patrick Esser, and Andreas Blattmann, the company builds powerful creative AI models from labs in Freiburg, Germany and San Francisco. Valued at $3.25 billion after raising $300 million in Series B funding, Black Forest Labs is at the forefront of generative media technology.

Super app platform enabling companies to embed lightweight mini-apps into existing mobile applications for payments, remittances, eSIM, lending, and marketplace features.

Browserbase provides cloud-hosted browser infrastructure purpose-built for AI agents and web automation. The platform enables developers to host, manage, and monitor headless browsers at scale with features including proxies, stealth mode, session recording, and debugging tools, serving over 20,000 developers.

Bureau is a no-code identity decisioning platform that uses AI-powered insights to prevent fraud in real-time. It serves over 200 global brands across fintech, banking, e-commerce, insurance, and gig economy sectors, having verified over 300 million identities.

BVNK is a crypto-native enterprise payments infrastructure platform enabling global stablecoin money movement. It provides APIs for businesses to send, receive, store, and convert fiat and digital currencies with managed custody and multi-jurisdictional licensing. BVNK serves fintechs, marketplaces, and enterprises processing at least $500K/month in payments.

Cal.com is an open-source scheduling infrastructure platform that enables absolutely everyone to build scheduling into their applications, providing a flexible and customizable alternative to proprietary scheduling tools.

CapitalOS provides embedded spend management infrastructure for vertical SaaS platforms, enabling business credit and spend controls via API integrations for platform customers.

Embedded credit card platform enabling businesses to launch and manage integrated credit card experiences. Partners include Coinbase, Bilt, Qatar Airways, and Alibaba.

Cartesia builds real-time voice and multimodal AI models with low-latency inference for production applications. Its platform combines foundational model research with developer APIs for voice agents, audio generation, and on-device intelligence.

Builds Large Physics Models that use AI to simulate atmospheric behavior for faster weather forecasting, producing predictions in minutes rather than hours via traditional supercomputers.

Census is a Data Activation and Reverse ETL platform that syncs data from data warehouses to business tools like Salesforce and Marketo. It enables data teams to operationalize warehouse data across the organization. Acquired by Fivetran.

Chalk builds a real-time inference data platform that gives ML and AI teams low-latency feature computation, retrieval, and production orchestration for online decisioning workloads.

Charm builds open-source tools and libraries for the command line, including Bubble Tea, Lip Gloss, and Glow, making terminal user interfaces beautiful and developer-friendly.

Checkly offers application monitoring powered by Playwright and OpenTelemetry so teams can test and monitor apps, APIs, and services as code.

Revenue automation platform that helps go-to-market teams route leads, qualify demand, book meetings, and coordinate handoffs across inbound and outbound funnels.

Clair embeds earned wage access and on-demand pay into payroll and workforce systems, using bank-backed infrastructure to deliver compliant short-term liquidity to workers.

Clerk provides developer-first authentication and user management infrastructure, including embeddable sign-in flows, session management, organizations, and backend APIs for modern web applications.

Cohere builds foundational AI models and enterprise solutions for search, generation, and agentic workflows. Their platform includes Command, Embed, Rerank, and the North agentic AI suite, enabling businesses to deploy secure, production-grade AI on private or sovereign infrastructure.

Column is a nationally chartered bank building developer-first banking infrastructure. It offers APIs and software for payments, ledgers, compliance, and bank programs so fintech companies can build on regulated banking rails.

Platform for standardized, open-source commercial contract templates and contract management tools, enabling software companies to negotiate and sign B2B agreements faster.

Common Room is an AI-powered customer intelligence platform that captures buying signals from multiple sources to identify potential prospects. It provides AI-powered enrichment and identity resolution to convert anonymous signals into identified buyers, helping go-to-market teams prioritize and act on sales opportunities.

Provides unified SDK and tools for connecting AI agents to SaaS APIs and secure credentials.

Convex is a backend-as-a-service platform for modern web applications, combining reactive databases, server functions, and auth-ready infrastructure.

Cortex is an internal developer portal and Engineering Operations platform that helps organizations reduce developer tax and improve operational maturity. It provides engineering teams with a centralized catalog of services, scorecards for reliability standards, and automation to foster ownership.

Courier is a developer platform for building and managing product notifications across email, SMS, push, chat, and in-app channels.

Crypto-integrated business banking platform that uses stablecoin rails alongside traditional payment networks.

David AI is the world's first dedicated audio data research lab, building the data layer for next-generation audio AI. Founded by former Scale AI engineers, serving most FAANG companies and major AI labs.

Daytona provides secure, elastic sandbox infrastructure for running AI-generated code and agent workflows, giving developers and AI agents isolated, programmable environments with fast startup and persistent state.

Dedalus Labs builds infrastructure for agentic AI, with products and APIs for deploying multimodal, multi-tool agents and experimenting with autonomous workflows in production.

Paris-based B2B lending platform providing API-first working capital financing to SMEs across Europe with loan decisions in 27 seconds, serving 17,000+ businesses across five countries.

Ditto builds an edge synchronization platform and mobile database that keeps apps in sync even when devices are offline or intermittently connected.

Double builds AI-native practice management software for accounting firms, combining bookkeeping workflows, task orchestration, and client operations into a single platform.

Dub is an open-source link attribution platform that powers short links, QR codes, conversion tracking, and affiliate programs for modern marketing teams. Used by over 1,000 companies including Twilio, Vercel, Perplexity, and Buffer, it provides advanced analytics and branded link management infrastructure.

Duffel provides a powerful API that enables developers and businesses to search, book, and manage flights and other travel products without the complexity of legacy travel infrastructure.

Eco builds stablecoin infrastructure for developers and businesses, enabling programmable money movement and one-click onchain payment flows.

Crypto exchange infrastructure company behind Phoenix, a decentralized exchange on Solana.

Emergent is an AI app-building platform focused on no-code and agent-assisted product creation, helping users rapidly build real applications with AI.

Enode provides an API that connects energy devices like EV chargers, batteries, and solar systems for energy apps.

Era is an AI-powered personal finance platform that connects bank accounts and financial data to AI assistants like Claude and ChatGPT via MCP. The platform offers proactive money management with AI-driven transfers, savings goals, and spending rules.

Fintech platform helping renters build credit through rental payment reporting to credit bureaus, reaching 228 million monthly active users through Zillow, valued at $1.2 billion

Builds encryption infrastructure for developers, including tokenization and PCI compliance tools for payments and sensitive data.

Embeddings-based search infrastructure providing a meaning-aware search API for AI applications. Exa trains embedding models to convert web pages into vector representations, enabling semantic search that understands intent rather than just matching keywords.

Fastest generative media platform for developers providing access to 1,000+ production-ready AI models for image, video, audio, and 3D generation through a unified API and serverless GPU infrastructure.

Finch is a unified employment API platform that enables HR tech, fintech, and benefits companies to securely read and write data across 250+ HRIS and payroll systems through a single integration. Founded via Y Combinator in 2020.

Fingerprint provides device intelligence APIs that help teams recognize returning visitors, prevent fraud, secure accounts, and reduce abuse across web and mobile products.

Finix is a full-stack payment processor and payments infrastructure platform that helps software platforms, marketplaces, and businesses accept payments, send payouts, manage risk, and build embedded payment experiences.

Finmid provides modular, API-driven embedded lending infrastructure for B2B platforms. The company enables platforms like Wolt, Glovo, and Bolt to offer financing solutions directly to their SMB customers across 30 European markets.

Firecrawl is a web data infrastructure platform that converts websites into clean, structured data optimized for AI applications through a simple API, turning entire websites into LLM-ready markdown or structured data.

Fish Audio develops multilingual AI voice generation and voice cloning infrastructure for creators and developers, with text-to-speech APIs and audio production tools.

Fixie (now Ultravox) builds real-time, speech-native voice AI models and developer tools for building fast, fluent conversational voice agents.

AI-assisted data exchange platform that helps teams collect, map, validate, and transform messy customer data before it enters core systems.

Flexprice is an open-source monetization infrastructure platform built for AI-native and SaaS companies. It enables teams to operate usage-based, credit-based, and hybrid pricing models with real-time metering and reporting, following an open-core model with self-hosted or cloud deployment options.

Flora is a node-based AI design tool and infinite canvas platform for creative professionals. The platform allows designers to build and automate creative workflows using a visual node orchestration layer, enabling creation of images, videos, and other media assets. Used by designers at Alibaba, Brex, Pentagram, and Lionsgate.

Folk is a modern, collaborative CRM platform designed for startups and agencies to manage relationships, streamline sales pipelines, and automate outreach. Built as an all-in-one tool that replaces traditional CRMs, it integrates with popular tools and enables teams to build genuine connections at scale.

Open-source financial infrastructure platform that provides programmable ledgers, payment connectivity, orchestration tools, and reconciliation services for building modern financial applications, trusted by companies like Booksy, Doctolib, Liberis, and Shares.

GraphQL-based ledger API giving fintech companies institutional-grade double-entry accounting infrastructure for real-time balance tracking, funds flow composition, and fault-tolerant money movement.

Froda provides digital financing and embedded lending products that help small businesses access working capital.

Funnel is a marketing intelligence platform that enables businesses to collect, prepare, and analyze data from various marketing channels. Founded in Stockholm, it provides pre-built connectors for data integration, marketing reporting, and advanced measurement capabilities.

Gecko is an AI-powered platform for equipment rental businesses that provides a 24/7 AI voice agent to answer inbound calls, check live inventory, and generate quotes in real time. It also handles daily operations through natural language prompts, replacing manual back-office work for rental operators. The platform has processed 1,000+ calls with 81% full automation rate.

Ghost is a non-profit organization building open source technology for modern publishing. It provides a professional blogging and newsletter platform with built-in email newsletters and paid subscriptions, used by publishers worldwide.

Gigs provides telecom infrastructure and APIs that let companies launch branded mobile services, phone plans, and connectivity products without becoming carriers.

GitBook is an AI-native documentation platform for technical teams that simplifies knowledge sharing with docs-as-code workflows and AI-powered search. Used by over 2 million users including Zoom and FedEx.

Gordian Software builds APIs that enable the world's leading travel organizations to increase revenue by seamlessly selling airline ancillaries and add-ons, serving over 60 million passengers monthly across 100+ airline partnerships.

Gradium is a Paris-based AI company building ultra-low latency voice foundation models that enable near-instant, expressive, and multilingual voice AI at scale. Spun out of French AI lab Kyutai, the company was founded by former Google DeepMind researchers who pioneered key advances in audio language modeling. Backed by a $70 million seed round from FirstMark Capital, Eurazeo, Eric Schmidt, and Xavier Niel, Gradium aims to make voice the universal interface for AI.

AI-powered code review platform that provides complete codebase context to help development teams automate pull request reviews, bug diagnostics, and enhance development workflows with intelligent code understanding.

Griffin is an API-first UK bank providing a full-stack banking-as-a-service platform for companies that need regulated accounts and payments.

Helcim provides payment processing software and merchant services for small and midsize businesses, combining payments acceptance, invoicing, subscriptions, and commerce tools in one platform.

Highscore is a cloud gaming platform that lets players run PC games from a browser or app across phones, tablets, TVs, Chromebooks, Macs, and Linux devices.

Hume AI develops empathic AI models and APIs for voice, speech, and expression understanding, including the Empathic Voice Interface for real-time emotionally intelligent conversations.

Hyperline is a billing infrastructure platform for B2B SaaS companies, enabling flexible pricing models, automated invoicing, and revenue recognition. It helps software companies launch and scale complex billing workflows without custom engineering.

Inference provides a distributed, serverless platform that lets developers run open-source AI models without managing infrastructure. The company aggregates underutilized data center capacity to offer cost-effective LLM inference via a simple API.

The developer platform for easily building reliable workflows with zero infrastructure, enabling serverless, event-driven backend workflows at scale.

Interhuman AI builds the social intelligence layer for AI systems, enabling them to read, interpret, and respond to human behavior in real time. Their technology combines body language, facial expression, and tone-of-voice analysis with contextual awareness to create more natural human-AI interactions.

Developer-first bug reporting tool that captures everything engineers need to debug in one click, including video replays, console logs, network requests, and reproduction steps.

Jeeves is a global financial infrastructure platform providing corporate cards, expense management, cross-border payments, and bill pay for businesses operating across 25+ countries. Founded in 2019 and valued at $2.1B, Jeeves enables companies to spin up their finance function within minutes.

Junction (formerly Vital) modernizes healthcare infrastructure with seamless lab testing and device data integration, connecting over 500 wearables and medical devices with 10+ lab networks including Labcorp and Quest across all 50 states.

CFTC-regulated prediction market exchange where users trade on real-world event outcomes across economics, politics, weather, and other markets.

Keel builds a modern, programmable ERP platform for operations teams, helping companies replace spreadsheet-heavy workflows with customizable internal systems they can launch quickly.

Keep is an all-in-one finance and spend platform for Canadian businesses, combining corporate cards, bill pay, expense management, and accounting workflows in a single system.

Automated bookkeeping and accounting platform for freelancers and self-employed entrepreneurs, streamlining expense tracking, tax prep, and financial management.

Open-source metering and usage-based billing platform that enables SaaS companies to build flexible pricing models with consumption tracking, subscription management, and payment orchestration.

Langbase is a serverless AI developer platform for building, deploying, and scaling AI agents. It processes 700TB+ of vector memory and billions of AI agent runs monthly, serving 100,000+ developers with support for 600+ LLMs.

Embedded accounting platform for SMB software companies, allowing platforms to offer complete accounting and AI-powered bookkeeping services directly within their products, fully replacing external tools like QuickBooks. Supports 30,000+ SMBs through platform customers including Moxie, Nav, Dripos, and Carry with 25%+ adoption rates.

Layercode provides voice AI infrastructure for developers, enabling production-ready, low-latency voice AI agents using TypeScript. The platform handles real-time audio processing across 330+ global edge locations with sub-50ms latency, supporting multiple LLM and voice providers.

Leen provides a unified API and data fabric for cybersecurity, helping security product teams, internal security teams, and MSPs integrate once with security tools and normalize vulnerability, endpoint, cloud, identity, compliance, and operational data.

Letta builds a platform and open source framework for stateful AI agents with memory, helping developers deploy autonomous agents that operate over long-running workflows.

LGND is building 'ChatGPT for the Earth,' a geospatial AI infrastructure platform that makes the world's satellite and geographic data as accessible and searchable as text. Using transformer-based geographic embeddings, LGND enables teams to create, adapt, and scale geospatial datasets across time and geography with reduced technical overhead.

Global payments infrastructure company building on Bitcoin and the Lightning Network, enabling instant low-cost money movement worldwide through APIs and SDKs for fiat, stablecoin, and bitcoin transfers.

Lithic is a modern card issuing platform for developers, enabling businesses to create, manage, and process virtual and physical payment cards via flexible APIs.

LiveKit is an open-source infrastructure platform for building realtime voice, video, and AI agent applications. Their platform powers products like OpenAI's ChatGPT Voice Mode, serving over 200,000 developers with billions of calls per year.

LlamaIndex is a data framework for LLM applications that enables developers to connect, index, and query custom data sources with large language models through their open-source library and LlamaCloud platform.

Post-purchase commerce platform that helps brands manage returns, exchanges, tracking, fraud, and other operations that protect margins and improve customer retention.

Loops is an email platform for SaaS companies with a block-based editor, transactional messaging, and automation workflows for product and lifecycle communication.

Embedded analytics platform enabling SaaS companies to build and deploy customer-facing dashboards directly into their products with drag-and-drop interfaces and code-based SDKs.

M0 builds programmable stablecoin infrastructure for financial institutions, providing minting, settlement, treasury, and compliance primitives for digital dollar products.

Mangrove builds a decentralized exchange with an on-chain order book and programmable liquidity for DeFi traders and market makers.

Marqo is a vector search platform that enables developers to build smarter search experiences with multimodal AI, improving conversion rates for e-commerce, recommendations, and content discovery.

AI model routing and interpretability platform using breakthrough Model Mapping technology to unpack LLMs into interpretable architectures. Intelligently directs prompts to best-suited models.

Mastra is an open-source TypeScript framework for building AI agents and applications, created by the team behind Gatsby. It provides modular tools for agent orchestration, tool calling, and workflow automation.

Medusa builds open-source commerce infrastructure and modular APIs that let developers compose storefronts, carts, checkouts, and backend workflows without adopting a monolithic commerce stack.

Mentium is an AI-native platform that builds digital workers for freight brokerages and logistics companies. Its agents automate high-friction back-office workflows including carrier load calls, accounts payable reconciliation, POD chasing, and settlement splits. The platform integrates with existing TMS, ERP, email, and phone systems, enabling customers to achieve up to 70% touchless task completion.

Merge provides a Unified API platform that lets B2B companies add hundreds of integrations to their products through a single integration. Covering HRIS, accounting, CRM, ATS, and file storage, Merge powers integrations for over 3,000 companies including Ramp, Drata, and AngelList.

Mesh builds crypto payments infrastructure that lets merchants and fintech platforms accept digital assets while settling instantly in stablecoins.

Method provides API infrastructure for consumer liability account connectivity, real-time debt data, and embedded repayment experiences across lending and fintech products.

Middesk is a business identity platform that automates business verification, risk assessment, and underwriting for financial institutions and enterprises. Backed by Sequoia, Accel, and Insight Partners, the platform enables companies to verify business identities quickly and accurately.

Mistral AI is a French AI company building fast, open-source, and secure large language models for developers and enterprises. Known for efficient, high-performance models offered via API and for self-hosting.

Mollie is a European payment service provider offering a simple, developer-friendly API for online payments, subscriptions, and financial services. It supports a wide range of payment methods across Europe, serving tens of thousands of businesses from startups to enterprises.

MoonPay is a cryptocurrency payment infrastructure platform that enables users and businesses to buy, sell, and swap crypto assets through credit cards, bank transfers, and other methods.

n8n is a fair-code workflow automation platform that enables technical teams to build complex automations with the flexibility of code and the speed of no-code, supporting 400+ integrations and self-hosted or cloud deployment.

Nace AI builds MetaModel, an AI system that dynamically generates small, task-specific language models for enterprises using a Hypernet architecture to inject task-specific weights in real-time without retraining. Their first product NAVI applies this technology to audit, compliance, and finance workflows.

Narmi provides cloud-based digital banking, account opening, admin, payment, AI, and API products for banks and credit unions, helping community financial institutions launch modern consumer and business banking experiences.

Native is a decentralized liquidity protocol enabling seamless cross-chain token swaps and DeFi integrations. It provides infrastructure for builders to embed native token exchange functionality into wallets, dApps, and exchanges.

Natural builds agentic payments infrastructure that lets AI agents, businesses, and consumers move money reliably. Its platform packages wallets, pay-ins, collections, credit, billing, transfers, compliance, and observability for real-world agent transactions.

Navattic helps revenue teams create interactive product demos that can be shared across sales and marketing workflows to accelerate evaluation and pipeline conversion.

Neon is a modern direct-to-consumer payment platform built specifically for mobile games, helping game publishers build branded digital stores and bypass costly app store fees while providing players with personalized experiences and publishers with higher profit margins.

Real-time patient booking and experience platform serving as an open data layer on top of EHRs, connecting patients, doctors, and healthcare developers with online booking, messaging, and payments.

Unified ingress platform providing developers with secure tunnels, reverse proxy, API gateway, and global load balancing used by over 7 million developers worldwide.

Nile is a Postgres backend for modern B2B SaaS applications, bundling multi-tenant primitives like auth, authorization, and tenant-aware data infrastructure.

Notion is an AI-enhanced all-in-one workspace combining notes, documents, wikis, and project management. With over 100 million users and $600M ARR, it has become one of the most widely adopted productivity platforms for teams and individuals.

OpenRouter provides developers with seamless access to 500+ AI models through a single unified API, eliminating the need to rewrite code or renegotiate contracts for LLM integration.

Orb is a modern pricing and billing infrastructure platform for software companies. It enables B2B SaaS companies to design, implement, and iterate on complex pricing models without engineering overhead.

Reinforcement fine-tuning platform (YC W25) that helps companies build task-specific AI models that outperform foundation models at a fraction of the cost, applying GRPO-style post-training without managing infrastructure.

Paid is a monetization platform for AI-native companies, enabling results-based billing for AI agents. Founded by Outreach co-founder Manny Medina, it lets agent providers charge customers based on value delivered rather than usage.

PaleBlueDot AI develops an AI platform and infrastructure stack for building and deploying AI applications, including agent workflows and model-powered products.

Parafin builds embedded finance infrastructure that lets platforms offer capital and financial services to small businesses.

Paragon is an embedded integration platform that enables SaaS companies to rapidly build and ship production-grade third-party integrations without building each connector from scratch.

Parallel builds web infrastructure for AI agents, providing APIs and tooling that let models search, browse, and interact with the live web more reliably.

Partly provides infrastructure and APIs for the auto parts industry, standardizing communication protocols and enabling automation across the supply chain for repairers, OEMs, and green suppliers.

Platform scaling unified climate action by helping organizations source, purchase, and manage carbon credits with efficiency, transparency, and rigor. API-first infrastructure for the voluntary carbon market.

Payman AI is an agentic AI platform for banking institutions that enables autonomous execution of financial transactions through conversational interfaces. The platform deploys AI agents that process payments, transfers, and account analysis via voice or text on existing banking rails, with built-in policy enforcement, compliance logging, and audit trails.

API-first loan management platform for lenders to automate servicing, payments, and compliance.

Construction permitting software simplifying permit preparation and submission process, known as the 'TurboTax for construction permitting' with automated workflows for contractors and developers.

Perplexity builds an AI-native answer engine and assistant that combines web retrieval with LLMs for consumer and enterprise search workflows.

Pinecone is a fully managed vector database that makes it easy to add vector search to production applications, powering AI applications with fast and scalable similarity search at any scale.

Pinwheel builds payroll and income data connectivity products for banks, lenders, credit unions, and fintechs, including direct deposit switching, income and employment verification, subscription management, and consumer-permissioned financial data APIs.

Playbook is a creative file manager designed specifically for designers, serving as a beautifully organized cloud storage and sharing platform. The platform uses image tagging technology to transform files into expressive Pinterest-style galleries, making it easy for designers to store, organize, and share their creative work.

Pliant provides a B2B credit card platform for corporate cards, virtual cards, cards-as-a-service, and payment process automation, helping companies control spend and integrate card data into finance systems.

Polar is an open-source billing and monetization infrastructure platform for developers and AI-native SaaS companies. It enables modern billing including subscriptions, usage-based, and events-to-billing in minutes with a few lines of code.

Leading 3D scanning and capture platform for iOS, Android, and web with LiDAR technology, photogrammetry, and 360° capabilities for creating professional-grade 3D models and floor plans.

Port is an agentic internal developer portal platform that helps engineering teams build autonomous workflows to accelerate software delivery. It provides a unified context lake, software catalog, AI agents, and workflow orchestration tools that integrate across the development toolchain.

Primer builds payment orchestration infrastructure for online merchants, giving teams a no-code workflow layer to connect processors, optimize routing, and manage the full payment stack through one integration.

Prisma builds an open-source ORM, Prisma Postgres, and related tooling for developers building modern data-intensive applications.

Prismic is a headless CMS and page builder designed for modern web development, enabling marketing teams to create pages independently while developers maintain control using frameworks like Next.js, Nuxt, and SvelteKit.

Pulse is a production-grade unstructured document extraction platform that converts complex PDFs, Word, Excel, and other document formats into structured, LLM-ready data. Built for enterprise reliability with OCR, bounding boxes, and vision language model capabilities.

Railway offers a cloud deployment platform that helps engineering teams ship and operate applications and databases with minimal infrastructure overhead.

Rainforest provides embedded payments infrastructure for vertical SaaS platforms, including merchant onboarding, payment operations, and payfac-as-a-service capabilities.

Rapider AI is an enterprise software development platform that connects company data so teams can find information faster and automate actions with AI and human expertise.

Universal API for real-time meeting data, providing developers with recordings, transcripts, and metadata from Zoom, Google Meet, Microsoft Teams, and other video conferencing platforms. Powers over 300 enterprise clients including Instacart and Sybill.

Reducto provides a high-quality AI document ingestion and parsing API for large language models. The Y Combinator-backed company processes nearly a billion pages monthly for leading AI teams like Harvey and Scale AI.

Reka builds multimodal foundation models and enterprise AI systems that combine text, image, audio, and reasoning capabilities for production applications.

AI model API platform that lets developers run open-source machine learning models for image, video, audio, and text generation via a simple API. Acquired by Cloudflare in November 2025.

Open-source multimodal data logging and visualization SDK for robotics and computer vision teams, enabling engineers to log, replay, and inspect spatial and temporal data.

Resend provides an email API and deliverability platform built for developers to send and manage transactional and marketing email.

AI voice platform enabling businesses to build and deploy AI-powered voice agents for phone operations, contact centers, and customer service. API-driven solution with natural, low-latency conversations and multilingual support.

Retool builds an enterprise application platform for creating internal tools, workflows, and AI agents on top of existing databases, APIs, and business systems.

Reworkd builds AI-powered web data extraction agents that automate the entire scraping pipeline at scale. Note: Company announced sunsetting as of February 2025.

Real-time interactive design and animation tool that enables designers and developers to create functional, ship-ready graphics with open-source runtimes that run fast and store small.

Riza provides isolated code execution infrastructure for AI-generated code and agent workflows.

Roboflow provides end-to-end computer vision tools that enable developers and enterprises to build, deploy, and manage vision AI models. The platform supports the full lifecycle from data labeling and model training to inference deployment, serving over 250,000 developers and powering applications across industries including manufacturing, retail, and agriculture.

RunPod is a GPU cloud infrastructure provider that enables developers, researchers, and AI companies to deploy and scale GPU workloads on demand. The platform offers serverless inference, on-demand GPU pods, and instant multi-node clusters, serving over 500,000 developers.

Runware provides a unified AI API platform that aggregates 300+ model classes and hundreds of thousands of AI model variants behind a single consistent schema, delivering up to 10x better price and performance for generative AI applications.

Unified API platform that connects business data across commerce, accounting, and payments platforms, enabling B2B SaaS companies to integrate financial data seamlessly.

Sanity builds a content operating system and structured content platform for developers and enterprise teams, with APIs, workflows, and AI-native content operations.

Sent provides a unified messaging API for SMS, WhatsApp, RCS, and other channels, handling routing, compliance, templates, delivery tracking, and fallback logic for developers building communication workflows.

Shortcut is a project management platform for product and engineering teams, combining planning, issue tracking, docs, and collaboration in one workflow.

Shovels builds construction intelligence software that turns fragmented building permit data into actionable market and go-to-market signals through APIs and analytics tools.

Slash is a business banking platform for internet entrepreneurs and high-spend businesses, offering virtual cards, corporate banking, treasury services, and developer-friendly APIs. Powers over $3B in annualized card spend.

Slate is building an AI sales engineer that helps go-to-market teams answer technical questions, complete security questionnaires, and create tailored demos faster.

Sling Money is a stablecoin-based global payment app that uses modern real-time payment systems, the Solana blockchain, and reserve-backed stablecoins to enable nearly instant and extremely low-cost transfers across 75+ countries, with all transfers currently fee-free.

Speakeasy is a complete API development platform that polishes OpenAPI, generates production-ready SDKs and Terraform providers, and builds MCP servers from OpenAPI documents with extensive customization options to connect LLMs to data wherever it lives.

Digital trust infrastructure enabling governments and enterprises to issue, verify, and manage digital identity credentials using open-source decentralized identity toolkits.

Stable Sea provides global stablecoin-to-fiat offramp infrastructure for businesses, enabling programmatic conversion of stablecoins to local currencies across 40+ countries through a unified API.

StackOne provides a unified API platform for product teams to ship customer-facing integrations quickly across SaaS systems.

Stedi is the only programmable, API-first healthcare clearinghouse, replacing legacy batch-and-portal clearinghouses with a modern cloud-native platform. It processes over 1 billion healthcare transactions per year.

AI-powered data platform that transforms unstructured web data and documents (websites, PDFs, pitch decks, reports) into structured, enterprise-ready datasets using their proprietary DoRa model that navigates and extracts data like a human, enabling real-time web extraction for business intelligence and data workflows.

Stytch provides developer-first authentication, identity, authorization, and fraud-prevention infrastructure, including APIs and SDKs for passkeys, SSO, MFA, device fingerprinting, and agent identity use cases.

Succinct is making zero-knowledge proofs accessible to any developer through SP1, their zkVM, and decentralized prover network that enables scalable blockchain applications and cryptographic infrastructure.

Supabase is an open-source Firebase alternative providing a full backend-as-a-service platform built on PostgreSQL, including database, auth, realtime subscriptions, edge functions, storage, and vector embeddings for developers.

Universal memory API and context engineering platform for AI applications. Provides long-term and short-term memory infrastructure for AI agents, powering enterprise APIs, developer plugins, and a personal knowledge app.

Swan is a European embedded banking platform that enables software companies to integrate financial services directly into their products via APIs. Licensed as an e-money institution by France's ACPR, Swan serves 150+ partners across 30 European countries.

Synthflow provides a no-code voice AI platform for building and deploying production phone agents for customer support, sales, and operations workflows.

Tako builds an AI data analyst that embeds into applications and returns cited answers with shareable visualizations across external and internal data sources.

Tavus is the human computing company building emotionally intelligent AI humans (PALs - Personal Affective Links) that communicate through text, voice, and face-to-face video with agentic capabilities and real-time perception. Powered by proprietary models including Phoenix-4, Sparrow-1, and Raven-1, Tavus enables AI agents that can see, hear, understand emotions, and act autonomously. Over 100,000 developers and enterprises use Tavus technology for recruiting, sales, education, and customer service.

Semantic KV caching layer built for LLM inference, enabling AI applications to reduce inference costs and latency by reusing cached computation across similar prompts.

Tera AI develops software-only, platform-agnostic spatial reasoning AI for autonomous robots. Their system enables zero-shot visual navigation across any robot type and environment without hardware modifications, using only existing cameras and onboard GPUs. Founded in 2023 by Tony Zhang (former ML lead at Google X), the company targets robotic manufacturers looking to expand autonomy across diverse platforms.

Thatch is a modern health benefits platform that enables employers to offer Individual Coverage Health Reimbursement Arrangements (ICHRA), giving employees a monthly allowance to choose their own health insurance plans. The platform has onboarded over a thousand companies and integrates with payroll systems like ADP to streamline benefits administration.

Nmbr is Canada's first dedicated embedded payroll software provider, enabling SaaS platforms and financial institutions to launch their own payroll products in days. The API-first platform handles the full complexity of Canadian payroll compliance and remittance.

Theo builds a full-stack platform that connects onchain capital to global financial markets and makes real-world assets tradable across crypto-native workflows.

AI research lab founded by former OpenAI CTO Mira Murati, building Tinker, an API for distributed LLM fine-tuning that makes model customization accessible without massive GPU infrastructure.

Tinybird is a real-time data platform that enables data and engineering teams to build real-time data products and APIs at scale. The platform ingests, transforms, and serves large volumes of data with sub-second latency for analytics and operational intelligence.

TinyFish provides enterprise web agents that automate complex web-based workflows and extract structured data from websites at scale. The platform enables Fortune 500 companies like Google and DoorDash to automate web interactions, streamline data collection, and integrate web automation into their business processes.

Tollbit provides a content monetization platform that enables websites to protect and monetize their content by allowing AI bots and data scrapers to pay for licensed access, creating a sustainable content ecosystem.

Trace builds voice AI infrastructure for financial-service customer interactions, focusing on call automation and support workflow execution.

Transcend is an enterprise-grade data privacy infrastructure platform that serves as the compliance layer for customer data. It enables organizations to automate data subject requests, map data across systems, manage consent, and activate data for AI responsibly at scale.

Consumer-permissioned data platform that provides API access to payroll, employment, and financial data for streamlined income and employment verification, asset verification, and direct deposit switching.

Turnkey provides secure, scalable, and programmable crypto wallet infrastructure for embedded wallets and onchain transaction automation. Built by the team that scaled Coinbase Custody past $100B in assets, it powers 50M+ embedded wallets.

TwelveLabs builds multimodal foundation models that understand, index, and search video content for developers and enterprises.

Unit provides embeddable banking and lending products that enable software platforms to integrate financial services—including accounts, money movement, card issuing, and capital products—directly into their products. Processes over $80B in annual transactions.

Open-source data preprocessing platform that extracts, cleans, and transforms unstructured documents (PDFs, images, HTML, emails) into structured formats optimized for AI and LLM pipelines.

B2B payments and cash collection platform that helps businesses automate invoice collection, reduce overdue payments, and provide seamless online payment options to their customers.

Vapi is building the leading developer platform for conversational voice AI agents, abstracting away the complexity of building these agents and managing real-time infrastructure to enable enterprise-ready voice AI solutions across finance, healthcare, travel, and other industries.

Vectara provides a retrieval-augmented generation platform with enterprise search, grounded generation, and evaluation tooling to help teams build production-grade generative AI assistants.

Volt is building the world's first global real-time payment network, enabling businesses to send and receive real-time account-to-account payments through a unified platform. The company harmonizes domestic payment schemes across 31+ territories.

Wiza is a B2B sales prospecting platform that provides real-time verified emails and phone numbers from LinkedIn, with 99%+ deliverability rates for outbound sales teams.

WorkOS is a developer platform that provides APIs for quickly adding enterprise-grade features like Single Sign-On (SSO), Directory Sync (SCIM), Audit Logs, and User Management to applications. Often described as 'Stripe for enterprise features,' WorkOS powers authentication and identity for the fastest-growing AI companies including OpenAI, Anthropic, and Cursor.

Xano is a scalable no-code backend platform that enables developers and non-developers to build APIs, business logic, and workflows without writing code.

YieldClub is a consumer crypto savings app that automates stablecoin yield strategies so users can earn real-time interest with no lockups and without needing deep crypto expertise.

You.com builds AI search and retrieval infrastructure for teams that need domain-specific, production-ready search inside their own products and workflows.

Zeal is a modern payroll infrastructure platform that enables staffing companies and platforms to onboard, pay, and bill workers through its API-first approach. The platform automates payroll compliance, tax calculations, and worker onboarding.

Zenskar is an AI-native revenue automation platform that handles billing, revenue recognition, collections, and analytics for SaaS and subscription businesses. Its AI agents automate contract processing and usage metering, eliminating manual finance workarounds for companies with complex pricing models.

ZeroEntropy provides a high-accuracy search API over unstructured data for AI agents and RAG applications. The YC-backed company builds smarter retrieval models enabling AI agents across healthcare, law, and sales.