/Companies

Y Combinator Summer 2021 (S21) Companies

389 companies from the Y Combinator Summer 2021 batch, with their investors and founders.

Truss

Truss Payments provides payment processing and financial services for builders and construction firms, including ACH and card payment acceptance, subcontractor payouts, corporate card issuance, and expense management.

4 investors

Tuli Health

Tuli operates a network of UK pharmacies that function as diagnostic hubs, offering blood testing and clinical services directly to patients and healthcare providers through a simplified booking and sample collection process.

2 investors

Turion Space

Turion Space builds space infrastructure spanning maneuverable spacecraft, mission planning software, and orbital logistics such as refueling and servicing, with capabilities for space domain awareness and rendezvous proximity operations. The company also develops technology aimed at extracting resources by mining near-Earth asteroids.

18 investors

Union54

Union54 operates ChitChat, a messaging and payments application that combines encrypted messaging with USD card issuance and international fund transfers for users in Africa. The platform addresses high remittance costs by offering lower-fee cross-border payment capabilities for consumers and small businesses.

4 investors

V-Flow Medical

V-Flow Medical develops medical devices intended to address the underlying causes of chronic pelvic pain in women, aiming to reduce opioid dependence and improve patient quality of life.

1 investor

Varos

Varos uses AI agents to automate business analysis work by conducting micro-interviews with employees to extract knowledge and generate decision-ready outputs like roadmaps and process optimization. The company serves enterprises seeking faster and more cost-effective business intelligence and analysis.

5 investors

VedaBio

VedaBio develops a molecular detection platform using CRISPR technology that enables rapid, accurate detection of multiple biological targets without the need for amplification. The platform serves research, diagnostics, and industrial applications across multiple markets.

3 investors

Verano Health

Verano Health operates an SMS-based telehealth platform that connects Medicaid patients with chronic diseases—particularly diabetes—to remote coaches for weekly check-ins and health education. The nonprofit targets underserved Americans who lack access to in-home disease management support.

1 investor

Verde

Verde provides digital lending services and loan origination tools to small and medium-sized farmers in Brazil, working through agricultural loan advisors.

1 investor

Verihubs

Verihubs is an AI-powered identity verification and risk decision platform that helps businesses verify identities, reduce fraud, and enable secure digital onboarding. The platform serves companies across multiple industries, with particular strength in Indonesia.

2 investors

Vibe Kanban

Vibe Kanban is a project management platform designed for teams working with AI coding agents, enabling parallel agent workflows and human review of AI-generated code. It provides tools for organizing work, managing multiple coding agents simultaneously, and reviewing automated code changes.

1 investor

Vinco

Vincoed manages educational programs and training across multiple institutions for organizations and their employees, offering services including preferential pricing, scholarship administration, coaching, and centralized payment processing.

4 investors

Vogent

Vogent is a platform for building AI voice agents that can handle phone calls, powered by custom conversational models and text-to-speech technology. It serves organizations across industries including healthcare and customer support, offering no-code agent building, call routing, and post-call automation.

4 investors

Wabi

Wabi provides a no-code platform for content creators and coaches in Latin America to build branded websites, manage online programs, and process payments in a single integrated system.

2 investors

WarpBuild

WarpBuild provides continuous integration and development infrastructure tools that speed up code building, iteration, and deployment for engineering teams.

1 investor

Warpfy

Warpfy builds a technology-led platform and ecosystem to help Indian and Asian brands expand into global B2C markets. The company operates four integrated platforms including an innovation lab, B2B wholesale distribution channel, brand partnership program, and learning community.

1 investor

Warrant

Warrant provides an authorization service that developers use to implement access control policies in their applications, offloading permission logic to a dedicated platform so engineering teams can concentrate on product development.

1 investor

Waterplan

Waterplan provides a platform that assesses water risk for industrial and consumer goods companies by combining operational data with satellite imagery, then recommends mitigation strategies ranging from infrastructure upgrades to ecosystem-based approaches.

8 investors

Whalesync

Whalesync enables two-way data synchronization between spreadsheet tools (Google Sheets, Airtable, Notion) and vertical SaaS applications (Webflow, Salesforce, HubSpot, Affinity), allowing teams to automate bulk data operations across platforms without manual CSV imports.

3 investors

Whaly

Whaly provides a data platform with enterprise-grade security and governance features for sales teams and data operations. The platform enables organizations to centralize data, manage access controls, and automate compliance while serving mid-to-large enterprises across industries.

1 investor

Writesonic

Writesonic is a platform for growth teams to monitor brand visibility across AI search engines (ChatGPT, Perplexity, Claude, Gemini) and take automated action through content creation, citation outreach, and technical fixes to improve AI search visibility and pipeline impact.

4 investors

Yemaachi Biotechnology

Yemaachi creates a diverse cancer bio-database to develop oncology drugs effective across diverse patient populations. The company develops precision oncology research, diagnostics, and therapeutics with a focus on inclusion for global communities.

3 investors

Yummy

Yummy is a Latin American super app that offers delivery services across multiple categories including food, groceries, transport, pharmacy, beverages, fashion, electronics, and events. The platform serves both consumers seeking delivery and merchants looking to expand their reach through a unified marketplace.

12 investors

Zage

Zage lets users make payments through bank transfers while accumulating rewards for their transactions.

2 investors

Other batches