Built with Fastly Spotlight: LeakSignal stops GenAI data leaks

June 18, 2024

In addition to providing industry-leading security tools, Fastly’s platform is a powerful ecosystem for startups and partners building innovative security solutions on the edge. We’re proud to be a part of a vibrant community of builders that makes the modern web faster, safer, and more engaging for all people. 


LeakSignal is a data flow governance solution that deploys as WebAssembly (WASM) on Fastly Compute. Designed specifically for observability and protection of data flowing within generative AI (gen AI) and modern workloads, LeakSignal classifies sensitive data in both inbound requests and outbound responses, ensuring comprehensive data governance without storing it. LeakSignal enables I/O Engineering[1] through a simple YAML policy, allowing organizations to protect their LLMs and route response traffic to protective guardrail LLMs via Fastly’s network with exceptional speed.


LeakSignal found that the biggest concern for corporations regarding gen AI is data leaks, not hallucinations, code errors, or bias according to recent executive surveys[2]. Data security is the top concern for 80% of companies when scaling AI solutions. Traditional solutions fail to provide real-time classification and monitoring of data as it flows through these complex systems. This gap in visibility and control makes it difficult to enforce data governance and mitigate potential data leaks effectively.

Bringing LeakSignal’s Solution to the Edge

By integrating LeakSignal’s data governance policies for LLM deployments on Fastly’s edge network, companies gain complete visibility and control over data flows in real-time. LeakSignal classifies and monitors data in-line within live LLM traffic without mirroring, storing, or copying it. This enables organizations to maintain robust data governance and instantly identify and prevent data leakage, hate speech, bias, and other LLM output concerns. In leveraging LeakSignal within Fastly’s network, organizations can achieve unparalleled speed and security in data processing:


Real-Time Monitoring: LeakSignal and guardrail LLMs work together to monitor and classify data flows in real-time, ensuring immediate detection and mitigation of threats.
Efficient Routing: Fastly’s network optimizes the routing of data between the primary LLM and the guardrail LLMs, maintaining high performance and minimal latency.
Scalability: The combined solution is highly scalable and capable of handling large volumes of traffic without compromising on speed or security.

The Power of Fastly’s Edge

Fastly’s edge platform provided unique advantages for Leaksignal as they explored options for bringing their technology closer to end users.


Superior WASM Support

Fastly’s exceptional support for WebAssembly (WASM) is a game-changer for LeakSignal. WASM allows developers to run code at the edge with near-native performance and robust security. This enables LeakSignal to deploy its data flow observability module seamlessly within Fastly’s compute environment. Fastly’s WASM support ensures that the module can execute efficiently, providing real-time insights and data classification without compromising speed or security.


Policy Storage with KV Store

Fastly’s KV Store is used for LeakSignal policy storage, providing a reliable and high-performance solution for storing and retrieving policies. This integration ensures that policies are consistently applied and updated, enhancing the overall security and governance framework of LeakSignal.


Developer-Friendly Tooling and Support

Fastly is exceptionally developer-friendly, with tools that work locally and simulate production environments. This enables the caching layer to be built confidently, knowing it will perform reliably in production. The ability to test comprehensively across the entire stack—edge layer, SaaS, and backend encryption—ensures the solution is secure and functional.


Performant, Available, and Secure

Customers depend on the core infrastructure for their services. With Fastly, a differentiated service layer ensures high performance and availability. Fastly’s robust support and reliable infrastructure are crucial for companies who leverage LeakSignal, helping deliver highly performant data security through in-transit classification.

How to Get Started with Leaksignal on the Edge

To get started with LeakSignal, sign up here. Reach out at getstarted@leaksignal.com For more information, visit the LeakSignal documentation.


LeakSignal is ideal for any organization deploying LLMs, especially those handling sensitive data. Gaining visibility into data flow is the first step; enabling rules for redaction and mitigation follows. The entire process is designed to be simple and user-friendly, leveraging pre-built configurations for ease of use.


If you’re  part of a team building something amazing on Fastly, we’d love to help spotlight the work you’re doing. Reach out to us in the Fastly Connect forum to get in touch.

[1] https://www.leaksignal.com/building-guardrails-for-large-language-models/

[2] https://www.cnbc.com/2024/05/16/the-no-1-risk-companies-see-in-gen-ai-usage-isnt-hallucinations.html