Participated · Seed · Aug 2026

Apollo Atomics focuses on shrinking and mass-manufacturing the steam generator—the largest component in many nuclear plants—by using a compact metal block with needle-thin channels to transfer heat more efficiently. Its design, based on MIT research, enabled the company to build a reactor it says is roughly 40-times smaller than ones using conventional steam generators and to assemble systems in a factory rather than on site. Apollo has built a 40-kilowatt demonstration reactor at MIT and plans to offer reactor sizes from about 10 megawatts-electric up to 300 megawatts. The company projects it can build a 300 MW plant in under 24 months and estimates the reactor will cost four to five times less to produce than existing designs. Apollo targets a levelized cost of electricity near 3 cents per kilowatt-hour and aims for commercial deployment in 2028. It participated in Y Combinator’s Spring 2026 batch.

Participated · Seed · Jun 2026

Sazabi builds an AI-native observability platform centered on chat, autonomous agents, and a logs-first approach that treats logs as the single source of truth for understanding production systems. The company aims to replace complex telemetry stacks and traditional dashboards by using AI to reconstruct views engineers need from log data and to proactively detect, investigate, and resolve issues. In a closed alpha it onboarded 50 teams in two weeks, ran 8,000 background investigations, detected 2,000 issues, and opened 200 pull requests against customer repositories. Sazabi says customers can onboard quickly — one cited customer reported a 15-minute onboarding and immediate useful alerts — and the product is being adopted by AI-native engineering teams. The company was founded in 2025 and is based in San Francisco. Following the seed raise, Sazabi plans to expand its engineering team, accelerate product development, and deepen integrations across cloud and developer platforms.

Participated · Seed · May 2026

Didit provides an API-first identity verification and fraud-prevention platform that connects to global government databases and analyzes over 200 signals per check, including document authenticity, biometric liveness, injection-attack detection, deepfake analysis and behavioral signals. The company builds its own AI models in-house and creates country-specific verification flows to reduce dependencies on third parties. Didit reports more than 1,500 B2B customers across fintech, crypto, marketplaces, mobility and government, and operations spanning more than 220 countries. The startup says it is already profitable and achieving monthly revenue growth above 30%. It is positioning Brazil as a strategic market, running pilots and integrations with local unicorns and banks while aiming to offer a reusable, global integration for customers expanding across countries. Long-term plans include creating a digital identity wallet that lets users validate once and reuse credentials across services.

Participated · Seed · May 2026

Luel operates a global contributor network spanning nearly 100 countries that is paid to record slices of everyday life, with submissions verified and rights-cleared before delivery. The company reports more than one million submissions processed through quality assurance and runs over 40 active data-collection campaigns. Its customer base includes frontier AI labs, robotics companies, hospitals, and banks. Luel positions itself to serve large markets for multimodal, robotics, speech, and computer-use training data. The company recently closed a $31.2M seed round led by General Catalyst and Lightspeed, which the article characterizes as one of the largest in YC history. The article did not provide revenue figures, a valuation, or a detailed breakdown of planned use of proceeds.

Participated · Seed · Apr 2026

Openlaw operates beglaubigt.de, a platform that digitises the end-to-end company formation process in Germany, handling document preparation, notary appointments and register filings while working with around 300 notary offices. The platform claims to reduce typical German GmbH formation timelines from six to eight weeks down to as little as three days and has served over 25,000 customers since launch. Beglaubigt.de is integrated with partners such as Qonto and counts customers or partners including Qonto, Holvi and Sevdesk. The company was accepted into Y Combinator's F24 batch and was founded by executives with prior exits and experience scaling startups. Openlaw's near-term plans include expanding the range of formation types and register processes, adding ongoing bookkeeping services, and scaling the product beyond Germany into other European markets. The fresh $3.3M seed financing is intended to accelerate those product and market expansion plans.