Discover the next generation of startups.

BeeSafe AI

YCombinator

Frontier AI Defenses for Social Engineering Attacks

BeeSafe AI is building the frontier model layer for social engineering defense. Cyberattacks have moved from code to conversation: attackers now use AI to carry out long-term, trust-based manipulation across SMS, voice, email, and social platforms, often inside encrypted channels where defenders cannot see, detect, or stop them. BeeSafe changes that by deploying undercover AI agents that engage attackers directly, expose hidden infrastructure, and convert live adversarial conversations into actionable intelligence. Each engagement adds to BeeSafe's proprietary dataset of real attacker behavior and trains foundational models that continually learn about counter-persuasion, deception, and manipulation in the wild. BeeSafe is starting in financial crime, where banks already value our data against Authorized Push Payment (APP) fraud and money laundering, but the opportunity is far broader. The same data and models that uncover mule networks today can protect consumers, secure enterprises, and strengthen governments against the next generation of AI-powered social engineering attacks tomorrow.

Bellabeat

YCombinator

Tech-powered women's wellness.

Founded in 2014, Bellabeat is a data-centered wellness femtech company behind some of the most fashionably designed tech-powered wellness products and one of the fastest-growing wellness subscription services for women. Throughout the years, Bellabeat built the go-to wellness brand with a compelling ecosystem of solutions and services focused on women’s health. The success of the Leaf and Ivy wearables enabled the brand to expand to international markets and kickstart industry discussions on the importance of innovating in the design and development of tech products. Today, Bellabeat is leading the market shift with hyper-personalized holistic wellness offerings aligned with a women’s menstrual cycle.

Benchling

YCombinator

Unlocking the power of biotech with modern software for modern science

Biotechnology is rewriting life as we know it, from the medicines we take, to the crops we grow, the materials we wear, and the household goods that we rely on every day. Biotech R&D is radically transforming our world, but to move at the new speed of science, scientists need better technology. Benchling’s mission is to unlock the power of biotechnology. The world’s biotech leaders and innovators use our R&D Cloud to power the development of breakthrough products and accelerate time to milestone and market.

BentoLabs AI

YCombinator

Monitoring and learning layer for long-running agents

BentoLabs is the monitoring and learning layer for long-running agents. We detect when agents silently fail or drift from the user's goal, system prompt, or tool contracts, show affected users and root cause, and suggest the prompt, skill, or harness fix. As more teams deploy agents, keeping them reliable in production becomes mission-critical. Bento sits directly in the production loop and gives teams the operational leverage required to scale agent ecosystems without scaling human firefighting alongside them. The result is a system that turns opaque agents into agents that can be monitored, debugged, and improved continuously. The founders learned this problem at Emergent (YC S24), where they built and operated production coding agents used by 5M+ users. Abhinav was hire #1 and helped Emergent hit SWE-Bench #1 and scale from $0 to $100M ARR in just 8 months. Kaushik was hire #2, led full-stack engineering at Emergent, and was key to building the infrastructure that made production agents reliable, observable, and debuggable. Bento's self-learning engine has also lifted ARC-AGI-3 (internal) by 2.6x and Terminal-Bench 2.0 (internal) from 42.2% to 52.4% pass@1 with the same model, tools, and budget.

BillionToOne

YCombinator

The genetic testing platform detecting and measuring disease.

BillionToOne has developed a DNA molecular counter that increases the cell-free DNA diagnostics resolution by over 1,000 fold, which unlocks transformative improvements in prenatal screening and liquid biopsy for cancers. Unity Screen, BillionToOne's commercially available non-invasive prenatal test (NIPT), is the only NIPT that can assess fetal risk for both recessive conditions and aneuploidies from maternal blood. UNITY Screen continues to grow exponentially and is on its path to becoming the next standard-of-care, with an increasing number of publications showing its accuracy and advantages over other screening methods. We have also recently used our molecular counting technology to develop liquid biopsy tests, which have the potential to completely transform oncology care.

BioStack Platforms

YCombinator

Real world training envs for healthcare AI models

BioStack is building the data engine for healthcare and drug discovery AI. The bottleneck is not models. It is access to high-quality biological data. Clinical and experimental data is fragmented, unstructured, and locked inside hospitals, labs, and CROs, while generating new data is slow and expensive. BioStack fixes this with proprietary clinical and preclinical data pipelines that turn real biomedical workflows into ML-ready training environments. We structure longitudinal multimodal data across imaging, EHR, and experimental assays, then package it for post-training and reinforcement learning so models can learn how research and care actually happen. Instead of static datasets, BioStack gives AI labs workflow-aligned data and environments that improve reasoning, decision-making, and real-world performance in biology and medicine.

Bird

YCombinator

The world’s largest omnichannel communications platform

. Bird CRM powers communication between businesses and their customers — across any channel, always with the right context, and on every corner of the planet. Its products and solutions are the foundational building blocks to business communications across preferred channels, like SMS, Voice, WhatsApp, WeChat, Messenger, Email and more. Founded in 2011, Bird connects to billions of devices and is trusted by nearly 20,000 customers worldwide. Headquartered in Amsterdam, Bird operates across nine global hubs — including Singapore, Dublin, Shanghai, Sydney, London, Bogota and Asuncion — and is proud to be a “Work Anywhere” company. Its team of 500 employees represent more than 55 nationalities.

Bitmovin

YCombinator

Powers OTT online video providers with video developer tools.

Bitmovin has been a first mover in almost every significant development in online video, from building and deploying the world’s first (and fastest) commercial adaptive streaming (MPEG-DASH/HLS) HTML5 Player, to being the first to achieve 100x realtime encoding speeds in the cloud. Bitmovin provides HEVC as well as VP9 live streaming with 60FPS and 4K resolution, and built the first containerized video encoding solution with Docker and Kubernetes. Bitmovin products are completely in-house developed, easy and fast to integrate and highly customizable. In combination with our great support, documentation and SLAs, this is a true enterprise offering. To find out more about Bitmovin’s video infrastructure solutions, or about any individual products, contact sales@bitmovin.com, or visit our website: bitmovin.com

Bizzy AI

YCombinator

Bizzy works 24/7 so you never miss a lead.

Bizzy handles your calls, captures and qualifies leads, and books appointments directly into your CRM. It understands your services better than a receptionist would, routes and escalates calls, and syncs with your existing tools to incorporate complex workflows, all so your team can focus on servicing leads, not qualifying them.