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21st
Infrastructure and UI building blocks for the agentic internet
21st.dev is the largest React component registry for AI applications, used by 2M developers (370K MAU). We provide the building blocks to create AI agents and agent-powered apps: UI components, agent templates, and an SDK with built-in UI, tools, memory, observability, and managed infrastructure.
83 Sciences
AI-native materials discovery powered by unpublished experimental data
83 Sciences uses AI to mine discarded experimental data and drive scientific breakthroughs. Working alongside labs, we discover the materials that will power the new Industrial Revolution.
AbInitio Bio
The Intelligence layer for Drug Manufacturing
Abinitio Bio builds foundation models for biomanufacturing, validated against wet lab data. Our first model, Echo, predicts manufacturing outcomes more accurately than standard models, and any pharma or CDMO can adapt it to their own workflow instantly. By making process decisions that take 6-18 months today in hours, we help teams avoid the cost of delay on a single program.
Absurd
The Creative OS for AI video
Absurd makes AI brand and performance ads at scale. Our last video for Kalshi ("Election Day") did 1M+ views, and our videos average 400K+ organic views. Companies like Hims, Kalshi, Replit, and Brex use Absurd to create production-quality videos in 72 hours. Try it at absurd.com
Adialante
Cancer screening without barriers
We know how to improve cancer outcomes by 8x-10x: you catch it early. MRI is the most robust and powerful cancer-detection tool in the world, yet systems cost millions to purchase, take months to install, and require high levels of technical skill to operate. We've redesigned MRI from the ground up with new physics, algorithms, and hardware, all to bring cancer screening to the entire world. Our mobile MRI is an imaging clinic on wheels. No equipment to buy, no infrastructure needed. For a flat per-scan fee, any medical site can offer MRI cancer screening. Starting with prostate cancer. Then everything else.
Advanced Metal Research
Machine intelligence for American Welding
America does not just need more welders. It needs welding knowledge that can scale. The American Welding Society projects 320,500 new welding professionals will be needed by 2029, with about 80,000 jobs to be filled annually from 2025 to 2029. More than 157,000 current welding professionals are approaching retirement. Welders are only a small share of the skilled-trades workforce, but welding accounts for an outsized share of projected capability demand. The market calls it a labor shortage. AMR sees a learning bottleneck. We are building American-made robotic welding cells that combine computer vision to provide real-time seam tracking and post-weld inspection to turn welding from a scarce manual process into a closed-loop manufacturing system that learns from every weld as it happens.
Aemon
The Forward-Deployed AI Research Engineer
Aemon is the first autonomous research engineer that delivers state-of-the-art solutions to your engineering problems. It generates, tests, and evolves thousands of approaches at machine speed to discover optimal solutions beyond what human experts can find. Aemon already set a new world record on an NP-hard math optimization problem with <$10 of compute, beating the previous record set by Google DeepMind in 2025. Ray and Richard (twin brothers) dropped out of UWaterloo and UIUC to build Aemon. They published at top AI conferences like ICLR and EMNLP before turning 20.
Agentic Fabriq
The control plane for AI agents.
Agentic Fabriq helps companies securely manage what AI agents can access and do across business tools, data, and teams. We give each agent an identity, scoped permissions, approval flows, and audit logs, so employees and customer-facing workflows can use agents without relying on shared API keys, overbroad service accounts, or one-off integrations.
AgentPhone
Phone Numbers for AI Agents
The $2T global telecom industry was built for humans. Agents can't act in the real world today because without a phone number, they lack identity. AgentPhone gives every AI agent its own phone number to reach people and businesses through messages and calls.
Agnost AI
Product analytics for teams building conversational agents
Agnost AI helps teams building chat and voice AI agents understand what users want, where they get stuck, and why they drop off. We read production AI conversations, cluster recurring intents, feature requests, frustration, and failure patterns, then open PRs against prompts, tools, and harnesses to improve the agent.