api
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Spade knows where your money went. Does your bank?
A payment can cross the world and still arrive with a name nobody recognizes. Spade is building the merchant intelligence that helps banks turn those cryptic records into decisions, rewards and fewer headaches.
Markup AI wants to check every word before you regret it
AI made the first draft cheap. Markup AI is betting that the expensive part comes next: deciding which words deserve to leave the building.
The Insurance Company Hiding in the Checkout
Tint turns a platform’s awkward coverage gap into insurance offered at the precise moment a customer needs it. Its founders learned the problem at Turo; now they sell the machinery, and sometimes the program, to everyone else.
Wonde wants school apps to stop asking for the same data
More than 30,000 schools use Wonde to connect their records with education software. Its business rests on a deceptively ordinary promise: change the class list once, and let the right apps catch up.
Golden Tried to Map Everything. Its $59.5 Million Lesson for AI Builders Was Knowing What Mattered.
Golden wanted to organize the facts Wikipedia missed. Seven years and $59.5 million later, its broad knowledge graph found a pointed job inside financial-crime intelligence - a useful lesson in turning ambitious AI infrastructure into something customers will buy.
Dari
Dari (YC F25) is a San Francisco startup building an API for reliable browser-use agents. Instead of calling an LLM on every run - which makes most browser agents slow, expensive, and non-deterministic - Dari learns a web workflow once, then caches the deterministic DOM steps so it can replay them reliably. It auto-handles 2FA (SMS codes, TOTP, email verification), detects when a site changes and adapts with AI, and exposes each automation as a versioned, stateful API endpoint. Founded by Caltech CS grads Avyay Varadarajan and Benjamin Hong.
Didit
Didit is a San Francisco-based identity and fraud infrastructure company building one API for KYC, KYB, AML, biometrics, liveness and transaction monitoring across 220+ countries and 14,000+ document types. Founded by identical-twin brothers Alberto and Alejandro Rosas, it offers 500 free verifications per month forever and pay-as-you-go pricing from $0.33 per KYC check, aiming to become the identity layer for an internet where telling humans from bots is getting harder.
Dojah
Dojah is a Lagos-based identity verification and anti-fraud infrastructure company that helps digital businesses onboard users, verify identities, and stay compliant through a single API and no-code tools. It aggregates KYC, KYB, AML, biometric, document and address checks across Africa and beyond, letting fintechs, banks, and marketplaces confirm who they are dealing with in seconds. A Y Combinator W22 company, Dojah serves customers including OPay, FCMB, Cowrywise and Fincra.
Interfaze
Interfaze is a San Francisco AI startup building a model purpose-built for deterministic developer tasks - OCR, web scraping, speech-to-text, object detection and classification - where consistency and verifiable output matter more than open-ended chat. Its hybrid architecture fuses specialized neural networks (CNN/DNN) directly into a transformer decoder, and the model ships as an OpenAI-compatible API with confidence scores, bounding boxes and metadata so developers can build rule-based systems on top. Founded by Yoeven Khemlani and Harsha Vardhan Khurdula, Interfaze is part of Y Combinator's 2026 batch and grew out of the team's earlier developer-API company, JigsawStack.
Miden
Miden is a Nigerian fintech building payments infrastructure for businesses across Sub-Saharan Africa. Through a single API, companies can issue virtual and physical cards in USD, NGN and multi-currency formats, run banking-as-a-service programs, open business accounts, and handle bill payments - the plumbing that lets other companies launch financial products without building banking rails from scratch. Founded in 2022 and part of Y Combinator's Winter 2024 batch, Miden has issued over a million cards and processes billions in transaction volume.
PayCaddy
PayCaddy is a Panama-based Banking-as-a-Service platform that lets Latin American companies launch financial products through an API. Businesses use its stack to open KYC-verified digital wallets, automate online payments, and issue branded Mastercard debit and prepaid cards - without building core banking infrastructure or negotiating directly with legacy banks. A Y Combinator Winter 2022 company, PayCaddy positions itself as embedded-finance infrastructure for emerging markets.
Plutto
Plutto is a Santiago-based KYB (Know Your Business) and due diligence platform for Latin America. It lets financial services, procurement, legal and compliance teams verify and continuously monitor the businesses they work with - vendors, clients and partners - by pulling legal, financial, tax and labor data from 15+ official sources, screening against sanctions and PEP lists, and producing auditable, AI-summarized risk reports. What once took lawyers weeks and cost about $100 per client now runs in minutes for a few dollars per check.
Terminal
Terminal is a universal API for telematics data in commercial trucking and fleet management. It connects to hundreds of telematics service providers - GPS, safety events, fault codes, dash-cam media, driver hours - and delivers that data in one normalized feed, so insurers, fleet software, logistics firms and fintechs can build products without wiring up hundreds of one-off integrations. Often called 'the Plaid of trucking,' the Toronto company was founded in 2023, went through Y Combinator's S23 batch, and has raised $26M to date.
Unifold
Unifold is a developer-first API and SDK that lets any app accept on-chain deposits across any blockchain and token in under 10 lines of code. It handles the full deposit flow - cross-chain routing, gas abstraction, compliance checks, and settlement - so users never have to think about chain IDs, bridging, or which version of USDC to use. Founded in 2026 by a team that previously built wallet infrastructure onboarding 30M+ users to apps like Phantom and Polymarket, Unifold is a Y Combinator Winter 2026 company based in New York City.
Unsiloed AI
Unsiloed AI builds an API that turns messy, multimodal documents - PDFs, scans, spreadsheets, charts and images - into structured JSON and LLM-ready Markdown. Founded by IIT Kharagpur alumni Aman Mishra and Adnan Abbas and backed by Y Combinator (Fall 2025), the company uses proprietary dual-stream vision models to parse, extract and split documents at scale, and ranks #1 on the public olmOCR-Bench, ahead of models from OpenAI, Anthropic and Google.
Vendy
Vendy is a Lagos-founded payment infrastructure company that lets businesses accept payments inside the places people already chat - WhatsApp, Instagram, Telegram and AI assistants. Sellers spin up a shop in minutes with a catalog, cart, automated invoicing and checkout, and buyers pay without downloading an app or signing up. Started in Y Combinator's W22 batch, Vendy now positions itself as 'agentic payments infrastructure,' offering a single API across cards, bank transfers, mobile money and USSD, and reports more than 20 million transactions processed for around 2,000 merchants.
NomuPay
NomuPay is a Dublin-headquartered payments company that gives enterprises a single API and unified platform to accept payments, disburse payouts and manage money across fragmented markets in Asia, Europe and the Middle East. Built partly from licences and assets of the collapsed German fintech Wirecard, its uP (Unified Payments) platform bundles local acquiring, more than 200 alternative payment methods and real-time payouts so global merchants can expand into hard-to-reach markets without wiring up a new integration for each country. It serves 2,000+ merchants and, after a June 2025 Series C from SoftBank's SB Payment Service, is valued at $290M.
Pomelo
Pomelo (Pomelo Group) is a London- and Singapore-based payments technology company that provides a unified, API-based Payment Platform-as-a-Service. It gives financial institutions, fintechs and enterprises ready-to-use payment rails, merchant onboarding and management, transaction monitoring, and a range of acceptance methods - from QR codes and tap-to-pay to payment links and card issuing - under a single white-label platform. Founded in 2017 as Pomelo Pay, the company has grown into a regulated e-money issuer serving 2,000+ businesses across the UK and Southeast Asia.
Formance
Formance is an open-source financial infrastructure company that gives developers a programmable core ledger and a connectivity layer for moving money across banks, payment processors, and wallets. Its stack - Ledger, Connectivity, Flows, and Reconciliation - lets fintechs and platforms track every asset movement with double-entry precision, orchestrate payments across providers, and automatically reconcile internal records against external statements. Founded in 2021 and backed by PayPal Ventures and Portage, Formance positions itself as building-block infrastructure for the 'financial internet' rather than a payment processor that touches customer funds.
Method
Method is a financial connectivity platform that lets developers link, read, and repay a consumer's credit and liability accounts - credit cards, student loans, auto loans, mortgages and more - through a single API. Using only a phone number, Method connects to 20,000+ financial institutions, surfaces real-time balances, payoff quotes and due dates, and moves money directly to creditors. It powers embedded lending, refinancing, balance transfers and debt payoff for fintechs and lenders including SoFi, Aven, Bilt, Happy Money and Figure.
OpenYield
OpenYield is a New York-based fintech operating an automated, all-to-all bond marketplace that brings an equity-like trading experience to fixed income. A FINRA-registered broker-dealer and SEC-registered alternative trading system (ATS), it offers firm, executable quotes with no minimum trade sizes across corporate bonds, municipal bonds and U.S. Treasurys, connected to brokerages, advisors, asset managers and market makers through API-first infrastructure.
SkyFi
SkyFi is an Austin, Texas-based Earth intelligence company that runs a self-service marketplace for satellite imagery and analytics. Through a single web platform, mobile app and API, customers can search archives, task satellites and buy optical, SAR, hyperspectral and aerial imagery from more than 50 commercial providers - then run built-in AI analytics on it. Founded in 2021 by Luke Fischer and Bill Perkins, SkyFi aims to make geospatial data as easy to order as a rideshare, serving defense, government, finance, energy, agriculture, insurance and infrastructure customers worldwide.
Stripe
Stripe is a financial infrastructure company that lets businesses accept payments and run their money operations through a set of developer-friendly APIs. Founded in 2010 by Irish brothers Patrick and John Collison, it powers everything from indie side projects to Fortune 500 checkouts, processing more than $1.9 trillion in payments in 2025. Beyond core card processing, Stripe offers billing, fraud protection, business incorporation, card issuing, tax automation, and banking-as-a-service, positioning itself as the economic layer of the internet.
Basis Theory
Basis Theory is a payments infrastructure company that gives merchants a cloud-native, PCI Level 1-compliant vault to tokenize, route, and control sensitive payment data across any payment service provider - without vendor lock-in. Founded in 2020 by fintech veterans from Dwolla, Yodlee, and Klarna, the company has raised roughly $50 million and now positions its vault as the foundation for AI-driven, agentic commerce.
Micruity
Micruity is a financial-technology infrastructure company building the data pipes that let lifetime-income products work inside everyday 401(k) plans. Its Advanced Routing System (MARS) acts as a secure central clearing house that connects insurers, asset managers, recordkeepers and plan sponsors, letting them communicate, verify and aggregate annuity data so retirement savings can be turned into a predictable monthly paycheck. Founded in 2017 by Trevor Gary and Chris Livadas, the company is headquartered in Toronto and raised an oversubscribed $20M Series A in December 2025.
Rightfoot
Rightfoot is a San Francisco fintech that gives lenders real-time, credential-less financial data - live bank and debit-card balances retrieved without asking borrowers to hand over bank logins. Its API and portal let lenders and collections teams verify account ownership, confirm a borrower can actually pay, and time outreach to when money is in the account, cutting failed payments and defaults. Founded in 2016 and originally an employer-enabled student-debt repayment tool, the company pivoted to permissioned data infrastructure and now serves consumer lenders, business lenders, and collections agencies.
Speakeasy
Speakeasy is a San Francisco developer-infrastructure company that turns an OpenAPI specification into production-grade, type-safe SDKs across ten-plus languages, then keeps them in sync automatically as the API changes. Founded in 2022 by Sagar Batchu and Simon Yu, it has expanded from SDK and Terraform-provider generation into an AI control plane for the Model Context Protocol - products like Gram and the MCP Gateway let companies expose their APIs as governed tools for AI agents. Speakeasy has raised roughly $26 million, including a $15M Series A led by FPV Ventures in 2024, and counts Vercel, Mistral AI, Clerk, Kong, Fivetran, Airbyte, and SolarWinds among its customers.
Apero Health
Apero Health is a San Francisco-based, Y Combinator-backed healthcare software company that folds scheduling, clinical visit notes, revenue cycle management, patient billing, e-prescriptions, and financial reporting into a single API-first platform. Founded in 2019 by Jacinda and Nick Shelly, Apero aims to bring transparency and speed to the notoriously opaque business of getting doctors paid - promising implementation in under a day, claim denials cut through custom validation rules, and payer enrollment across all 50 states.
Neural Defend
Neural Defend is a New York and Delhi-based cybersecurity startup building multimodal deepfake detection for enterprises. Founded in 2024 by MIT- and Intel-affiliated researchers, its proprietary AI spots AI-generated faces, manipulated video, cloned voices, and forged documents in real time - delivered as developer-friendly APIs and SDKs, plus on-premises deployments for banks, fintechs, and government. The pitch: make catching a deepfake as easy as an API call.
SpeakIn Technologies Co.,Ltd.
SpeakIn Technologies is a voiceprint-recognition and identity-security company founded in Silicon Valley in 2015 and headquartered in Shenzhen. Using deep neural networks and its iVector engine, SpeakIn turns the unique physical signature of a human voice into a biometric key, offering both 1:1 verification (is this the right speaker?) and 1:N identification (who is speaking, out of many?). Its SDK and cloud APIs are used across banking, public security, and smart devices, with reported accuracy near 98% and customers including Tencent, Lenovo, ASUS, and China Merchants Bank.