Sealed Developer Tools

Sealed offers a suite of provably-local developer tools designed to handle sensitive information entirely within your browser. This means your secrets, such as signing secrets, private keys, and session tokens, never leave your browser tab. The flagship tool, hooksig, allows you to verify webhook signatures from 10 different providers, showing you exactly what each provider signs. Another tool, Cert workbench, enables you to inspect X.509 certificates, displaying details like subject, issuer, validity, key type, SANs, and whether they are CA-signed or self-signed, all decoded locally. Additionally, the HAR sanitizer helps you remove cookies, tokens, and Personally Identifiable Information (PII) from HAR files before sharing them with support.

The core principle behind Sealed tools is to eliminate the need for trust in external servers. By running entirely in your browser, these tools ensure that your sensitive data is never uploaded or exposed to a backend. The technology stack leverages WebCrypto APIs and a Rust core compiled to WebAssembly, performing all operations directly on your machine. This architecture guarantees zero network requests for processing secrets, making the tools static pages that are open source and MIT-licensed for complete audibility. You can verify the code yourself and observe the network tab to confirm that no data leaves your browser.

• Runs in your browser: Utilizes WebCrypto and a Rust-to-WebAssembly core for local processing.

• Nothing leaves your tab: No backend, no uploads, no telemetry ensures maximum privacy.

• Open and auditable: All tools are MIT-licensed on GitHub, allowing for verification.

Sealed provides a secure and transparent way to handle sensitive developer data, offering peace of mind through its architecture rather than relying on privacy policies.

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