Circle is opening up Arc ahead of launch, letting outsiders test its blockchain before its mainnet goes live.
Stablecoin issuer Circle is opening up Arc, its own blockchain for stablecoin payments, to outside scrutiny before launch.
In a blog post on Thursday, April 9, the USDC▼$0.9998 issuer said it’s releasing testnet code, launching a HackerOne bug bounty, and letting developers run their own nodes. Here’s how the company framed the move:
“Together, these steps expand the review surface before Arc mainnet and create a clearer path for researchers, audit firms, and infrastructure teams to inspect, test, and challenge Arc before capital is at risk.”
Read also: Circle Faces Potential Class Action Lawsuit Over $285M Drift Hack
Circle Warns Against Testing on Public Testnet
The stablecoin issuer also stressed that bug bounty testing “must happen locally,” asking researchers not to run experiments against Arc’s public testnet. The company added that submissions need a working proof of concept, version details and clear steps to reproduce the issue. Circle explained:
“We are interested in vulnerabilities where an external party runs a crafted node or sends crafted transactions or messages to attempt to break, slow, trick, or leak information from correct, unmodified Arc nodes.”
According to Circle’s HackerOne program, payouts are structured in tiers based on severity. Lower-risk findings typically pay between $150 and $400, while mid-level issues fall in the $400 to $800 range. More serious vulnerabilities can earn between $3,000 and $5,000 for the most critical cases.
Circle first launched Arc’s public testnet in October 2025 as an open Layer-1 blockchain built specifically for stablecoin payments and tokenized financial activity.
Read more: Circle Unveils Roadmap to Shield Arc Blockchain From Quantum Threats
