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Silmaril

Prompt injection defense that self-improves

Spring 2026B2B / B2BSan Francisco, CA, USA2 employees
Developer Tools
Security
Cybersecurity
AI

About

Silmaril is a prompt injection defense that self-improves for AI native applications and agents. It understands application context to block 2x as many threats as current SOTA defenses with 10x lower latency. Customers plug us into agentic frameworks like LangGraph with 5 lines of code. Silmaril has stopped $28M of damages for customers.

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Founders (2)

Aum Upadhyay
Founder
Eduardo Velasco
Founder

Details

Status
Active
Stage
Early
Team Size
2
Regions
United States of America, America / Canada
Silmaril | YC Companies | GPAgent - GPAgent