Y Combinator Summer 2026 (S26) Companies

Tsenta automates job applications by monitoring 50,000+ career pages across major applicant tracking systems and submitting tailored, ATS-optimized applications within minutes of job postings. The platform serves active job seekers seeking to increase application volume and speed while maintaining quality application materials.

1 investor

Ultrasonium is a company focused on materials science and advanced manufacturing, developing engineering systems.

1 investor

Understudy Labs offers an open-source toolkit that captures traces from LLM production workflows, benchmarks and A/B tests cheaper or open-weight models against them, and fine-tunes and deploys specialist models that users own and can host anywhere. It is aimed at developers and teams looking to migrate from proprietary LLMs to models they control.

1 investor

Vendo provides a customization layer that enables end users to build custom features and integrations within an existing product without requiring code changes, using the host product's APIs and design system while maintaining security isolation.

1 investor

Verdant is a software platform that manages the full planning and permitting workflow for local government agencies, from resident inquiries through final commission votes. It provides configurable modules for intake, plan review, and code research tailored to individual municipal ordinances and workflows.

1 investor

Vestris is an AI platform that automates mortgage title and closing operations, handling tasks such as contract parsing, title abstract generation, tax prorating, and title commitment issuance for title companies and lenders. It uses browser agents to access county records and coordinate with all parties involved in the closing process.

1 investor

Waddle Labs provides an API that connects to robots and, from a natural-language prompt, uses AI agents to generate a control policy for the robot to carry out the requested task. The product targets robotics developers and operators.

1 investor

Whitespace provides AI agents that analyze business data to forecast demand, recommend inventory order quantities, and automate inventory management processes for wholesale distributors and manufacturers.

1 investor

Wondering is a mobile learning app that breaks down topics such as machine learning, quantum mechanics, and product design into short lessons combining visuals, podcasts, and interactive exercises. Its learning paths are tailored to each user's background, learning style, and desired depth.

1 investor

Zaplar is an autonomous operations platform for hotels that unifies rooms, events, spa, F&B, guest messaging, booking, and point-of-sale into one system. It automates routine work while letting staff review and approve suggested actions, aiming to reduce administration and capture more upsell for hoteliers.

1 investor

Zomma Labs builds AI agents that automate repetitive work and system operations, enabling teams to focus on higher-value tasks. The platform is designed for enterprise organizations seeking to augment their workforce capabilities rather than replace workers.

1 investor