After interviewing eight investors, TechCrunch identified the 11 most-watched startups from Y Combinator’s Spring 2026 Demo Day. These projects are concentrated in AI agents, developer tools, robotics, defense technology, and aerospace manufacturing, with some companies’ valuations already exceeding $175 million.
Valuation continues to rise
The report notes that fundraising momentum for this YC cohort continues to rise. At least two companies have reached or exceeded a $175 million valuation, with seasoned serial entrepreneurs attracting particular interest from investors.
Among them, the anti-drone system company 9 Mothers is one of the most discussed projects among investors. The company claims its robots can track and shoot down low-flying drones traveling at 60 miles per hour. According to investors cited in the report, the company’s valuation may have exceeded $200 million, making it one of the highest-valued projects of this cohort.
9 Mothers, founded in 2024, has recorded $1.6 million in sales. Reports indicate that one contract is expected to expand to $35 million later this year, and the company has shown investors the potential for a $1 billion pipeline of contracts.
AI tools remain the main focus.
In the software and development tools category, Agra Labs, Lightsprint, Sazabi, and Superset were all named by multiple investors.
Agra Labs aims to address the issue of testing lagging behind AI-generated code. Its product enables enterprises to rapidly create "digital twin" environments, allowing AI agents to test code in an isolated setting before deploying it to production systems.
Lightsprint is designed for non-engineering roles, enabling product managers to directly generate app features using natural language and visual options, which engineers then review and merge. Sazabi focuses on resolving online incidents by analyzing logs, identifying issues, and generating one-click fixes. Superset aims to centrally manage a large number of coding agents, enabling developers to run over 100 agent tools simultaneously.
Security and automation are of concern
In addition to development tools, AI security and enterprise automation have also attracted significant attention. Silmaril focuses on AI security infrastructure, primarily defending against attacks such as prompt injection. Its system automatically detects new threats and retrains firewalls.
Complir targets cross-border product compliance. The company aims to use AI agents to help businesses track regulatory changes, generate required documents and product labels, and reduce compliance costs in cross-border sales.
The website and marketing automation company Ploy was also featured on the trending list. Around the time of the report’s publication, Ploy announced it had completed a $27 million seed round led by First Round and Y Combinator. Founded by Bryant Chou, co-founder and former CTO of Webflow, the platform automatically generates landing pages, writes marketing copy, and launches promotional campaigns.
Healthcare and aerospace projects shortlisted
In addition to AI software, this year’s Demo Day also featured a few projects with a stronger focus on hard technology. Adialante is developing a mobile MRI clinic aimed at making early cancer screening more accessible at a lower cost. The company plans to install compact MRI equipment in small trucks and charge on a per-use basis.
The space-focused Dispatch is tackling the challenge of retrieving products after space manufacturing. The company is developing reusable return vehicles aimed at safely bringing back drugs, semiconductors, and other products manufactured in microgravity environments to Earth. Reports indicate that some investors are betting that the commercialization of space manufacturing could progress faster than market expectations.
Overall, this year’s YC Demo Day still focused heavily on AI, but investment preferences have shifted from broad narratives to more specific use cases, including code testing, agent management, security protection, marketing automation, and applications integrated with defense and aerospace.