Doppel, a cybersecurity company developing AI-powered social engineering defense technologies, has acquired PropRise, a Y Combinator-backed technology startup founded by former Stripe employees Jean-Michael Diei and Matthew Krager. The acquisition will bring PropRise’s founders into Doppel’s engineering organization as the company expands its agentic AI capabilities and invests in technology designed to counter increasingly sophisticated cyber threats.
Founded in 2023, PropRise developed its business to a high-six-figure annual recurring revenue level before the acquisition.
Diei and Krager bring experience developing and scaling technology products, including prior roles at Stripe and participation in Y Combinator.
Their addition strengthens Doppel’s engineering team as it continues building a platform designed to detect, investigate, and disrupt social engineering attacks.
Doppel’s technology combines digital risk protection, human risk management, and email security to address cyber threats involving impersonation, phishing, fraud, and deception.
The company’s platform uses agentic AI to identify relationships among threats appearing across different digital channels.
Its Digital Risk Protection capabilities monitor potential attacks and identify infrastructure associated with malicious activity.
The Email Security offering evaluates incoming messages and the infrastructure behind them, seeking to identify and disrupt phishing campaigns.
Doppel’s Human Risk Management technology helps organizations prepare employees for social engineering threats by turning real-world attack patterns into simulations and training exercises.
These capabilities operate through a shared intelligence architecture that connects information across the company’s security products.
Doppel’s Threat Graph allows signals identified through one security capability to inform defenses elsewhere in the platform.
The company also uses AI agents intended to identify missed detections and improve protection against emerging attack methods.
The acquisition of PropRise reflects Doppel’s emphasis on recruiting technically experienced founders and engineers capable of developing new cybersecurity products.
Doppel co-founder and CTO Rahul Madduluri highlighted the importance of strengthening the engineering organization as artificial intelligence changes how attackers conduct social engineering campaigns.
Diei and Krager will contribute product development expertise to Doppel’s broader social engineering defense platform.
Their arrival follows a period of expansion for the company.
During 2026, Doppel established a larger international presence through operations in Japan and Toronto.
The company also introduced additional capabilities across its cybersecurity platform and surpassed 300 employees.
Doppel is backed by investors including Bessemer Venture Partners and Andreessen Horowitz.
Its strategic investors also include CrowdStrike CEO George Kurtz.
The company has received industry recognition, including inclusion on Fast Company’s 2026 Best Workplaces for Innovators list and the 2026–2027 Fortune Cyber 60.
The acquisition adds engineering talent and startup-building experience to Doppel as it develops cybersecurity technologies addressing the growing use of AI in fraudulent communications and digital attacks.
KEY QUOTES
“We’ve built an engineering team that thrives on solving the world’s hardest problems, and Jean-Michael and Matthew bring the exact kind of founder mentality and builder experience we want at Doppel. As AI transforms social engineering at breakneck speed, it’s vital that we challenge assumptions, adapt quickly, and build what hasn’t been built before. I’m excited to welcome Jean-Michael and Matthew to the team as we continue bringing together some of the best technical talent in the industry to define what comes next.”
Rahul Madduluri, Co-Founder And CTO Of Doppel
“We’ve spent the last three years innovating at the frontier of agentic AI. As cybersecurity threats grow increasingly complex, we see an enormous opportunity to bring that experience to a new generation of agentic defense solutions. We’re excited by the caliber of Doppel’s team, the technical problems they’re tackling, and the company’s rapid growth.”
Jean-Michael Diei, Co-Founder And CEO Of PropRise
