Build: Public launch June 30, 2026
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Build Public launch June 30, 2026. Build is a neofirm of autonomous AI services for the built world — real estate development and infrastructure. Its agent platform, Dougie, automates site selection, feasibility analysis, due diligence, and design development, compressing roughly four weeks of human work into about 75 minutes.
Executive summary
Raised $8.5M seed led by Index Ventures with Pebblebed (OpenAI and Meta AI Research co-founders), Sarah Friar (OpenAI CFO), and John Stecher (Blackstone CTO) as angels. Completed 150+ projects across 18 countries for Fortune 500, hyperscalers, and governments managing more than $2T in assets collectively.
Why Build became a trending topic
- Raised $8.5M seed led by Index Ventures with Pebblebed (OpenAI and Meta AI Research co-founders), Sarah Friar (OpenAI CFO), and John Stecher (Blackstone CTO) as angels.
- Completed 150+ projects across 18 countries for Fortune 500, hyperscalers, and governments managing more than $2T in assets collectively.
- Founder James Stirrat-Ellis is an architect who left Harvard, worked on Singapore Changi Airport expansion ($13B), and taught himself to program.
- Tripled booked revenue since April 2026; contracts start in six figures.
- Coined the category term agentic real estate.
From Changi-scale infrastructure to agentic real estate
Founder James Stirrat-Ellis left Harvard’s architecture track to work on Singapore Changi Airport’s $13B expansion —
a credential that signals comfort with megaproject complexity, not residential brokerage tech. Teaching himself to program
bridged design intent and software execution, a combination legacy AEC firms rarely house in one role.
Index Ventures leading an $8.5M seed with Pebblebed (whose founders co-founded OpenAI and Meta AI Research) places Build
in the same capital narrative as frontier-model infrastructure — but applied to physical-world workflows. Angel participation
from OpenAI CFO Sarah Friar and Blackstone CTO John Stecher links AI governance and institutional real estate capital in one cap table.
Build reported tripling booked revenue since April 2026 and completing 150+ projects across 18 countries before the June 30
public launch — metrics that explain why English-language outlets from Fortune to SiliconAngle treated the debut as a category
defining moment rather than a feature launch.
Funding and backers
$8.5M seed (2026) — Index Ventures, Pebblebed, Puzzle Ventures, Sarah Friar, John Stecher
Figures reflect July 2026 press coverage from PR Newswire, TechCrunch, Fortune, SiliconAngle, Tech Funding News, and EIN Presswire.
Verify round terms on primary sources before investment or partnership decisions.
Leadership
James Stirrat-Ellis (CEO) and Ben McClusky (co-founder)
Competitive context in NYC
Headquartered in Manhattan, Build launches into a market where four startups dominated July 2026 tech headlines.
Unlike generic “startup listicles,” this analysis ties each claim to directory dossiers with 20+ source URLs per company.
Related guides: startup funding NYC 2026,
50 NY founded companies 2025–2026,
IT companies NYC.
Primary sources
Reviewed by: Michael Torres, Technology & financial data analyst.
See our Editorial Process for methodology and corrections.
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