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Guillaume Roux-Romestaing

Guillaume Roux-Romestaing

Growth operator, investor and a16z scout focused on AI startups.

grx
San Francisco, California
Joined October 2025
Favicon imageblog.wordware.aiFavicon imagesifted.euFavicon imageapp.growthmentor.comFavicon imageproducthunt.comFavicon imagelinkedin.comFavicon imagex.com

Network

8.6K connections

Summary

Growth operator for AI startups — hands-on GTM and product-led growth work at early-stage AI companies (Wordware, 11x.ai). He builds growth experiments, partnership motions and viral demos that demonstrate product value and drive user acquisition. wordware+2
Investor and scout — runs an angel syndicate (181 Angels) and serves as a scout for Andreessen Horowitz, combining operator experience with active angel investing and deal-sourcing in the Bay Area / Europe corridor. 181angels+2
Venture-building and strategy background — several years advising, building and doing M&A/strategy work across the Founders Forum ecosystem and Founders Intelligence, giving him exposure to early-stage product strategy, venture scale challenges, and corporate/strategic transactions. wordware+1
Builder of AI product demos and content — authors Wordware blog posts that both explain product capabilities (VC analyst agent) and show growth-focused, high-impact demos (Twitter Roast AI), indicating strengths in LLM orchestration, product marketing, and building viral demo experiences. wordware+1
Active mentor and public-facing adviser — profiles and author bylines show frequent mentoring, public writing, and speaking; he positions himself as a practical, operator-investor who helps founders with fundraising, GTM and hiring. growthmentor+1

Work

Education

Projects

Writing

How We Built a Viral Twitter Personality & Roast AI with Wordware

May 1, 2025

Post describing how the team built a viral Twitter-based AI demo (Twitter Roast AI) with LLM orchestration and structural design for virality and conversion.

Favicon imageblog.wordware.ai

Unveiling our VC analyst agent

March 1, 2025

Wordware blog post/demo describing an autonomous VC analyst agent that structures pitch-deck analysis, desk research, and investor workflows.

Favicon imageblog.wordware.ai

'Europe is the funny little cousin' — 11x on why it's moving to Silicon Valley

October 1, 2024

Opinion piece explaining why 11x (and similar European AI startups) are relocating to the US and the implications for growth and scaling.

Favicon imagesifted.eu

Hobbies

Mentoring founders and founders-in-training (advising, pitch practice, growth coaching). growthmentor+1

Early-stage investing and syndicate curation (angel investing). 181angels+1

Notes

MSMikhail Sidakovsaid that if they were building a startup,
GRGuillaume Roux-Romestaing
would be among their top choices as an angel investor.

Jun 13, 2026

MSMikhail Sidakovsaid
GRGuillaume Roux-Romestaing
has been a standout founder or early team member who meaningfully advanced both business and technical sides of an AI startup.

Dec 6, 2025

MSMichael Schneidersaid
GRGuillaume Roux-Romestaing
stood out to them as a founder who’s built and led high-impact go-to-market or sales teams.

Aug 7, 2025