Mura: A Web3 Application for Digital Evidence Preservation

Abstract

This paper describes the implementation of Mura, a Web3 application for digital evidence collection and preservation (DECP) designed to serve public figures and lawyers as they prepare libel lawsuits. The platform is Brazil’s first blockchain-based solution to be Chain-of-Custody compliant, as required by the Brazilian Criminal Procedure Code, and cost-effective. It uses a headless browser to generate a PDF of a target web page from a sandbox environment, appending additional metadata to create a technical report of the collected evidence. Finally, it derives a Solana address from the report’s SHA-256 hash – to which it sends a small amount of SOL, such that the transaction serves as the evidence’s auditable and highly available Proof of Existence. Through this simple yet robust architecture, Mura could charge the most affordable market rates at R$1 per report (94% cheaper than the second most affordable competitor) while maintaining profit margins of over 98%. Furthermore, its security guarantees match those of established startups (e.g., Verifact and OriginalMy) by ensuring the authenticity, integrity, availability, and confidentiality of evidence collected from public domains, which makes it Chain-of-Custody compliant. Ultimately, Mura accomplishes such goals for desktop and mobile versions in a low-latency, self-sufficient application.