Arc

The Economic OS for the internet. Now live in public testnet.

[Arc @arc]

Arc Public Testnet is now live.

Open to developers and enterprises globally, Arc is the Economic OS for the internet that unites programmable money and onchain innovation with real-world economic activity.

Start building: https://t.co/XmFdy0SG5g
Learn more: https://t.co/JOGsf9Ma5V

[bobbilee | Arc Architects Lead @ Circle @bobbilee]

icymi 👀 tune in all day june 9

https://t.co/xtozZYY0SM

[Arc @arc]

AI agents need infrastructure that can match the speed and determinism of software.

Arc gives developers a more usable foundation for the agentic economy with:
→ Gas paid in stablecoin (starting with USDC)
→ Sub-second deterministic finality
→ Programmable settlement logic
→ Opt-in transaction privacy

That makes it easier to build systems where agents can transact, coordinate, and settle value in real time.

[HJ Chen @hj_chen]

“Pay first, settle later” with Circle CCTP

Fulfiller pays the recipient instantly on the destination chain, then gets reimbursed later by the platform via CCTP.

Demo running with an agent harness (Arc Testnet → Sepolia)

Clone the repo at https://t.co/rDEPKWmS5m

[Arc @arc]

Arc Moves Fast. This Does Not.

Watch what Arc was built to leave behind.

June 9.

https://t.co/G2L20rZHfz

[Sam | Circle and Arc Community @samconnerone]

Five employees at Boream & Boredley wait for approvals, updates, and the future economy to arrive. Join the livestream June 9 at 8AM PST.

Set a reminder to watch this absurd event about the absurdity of old financial rails.

https://t.co/ZZJn8NpCYl

[Rachel Mayer @0xrachelita]

Boredom is status quo prior to Arc.

Experience it live from the Bored Room

[USDC @USDC]

Slow work day? Perfect.

On June 9, join The Bored Room: a livestream about waiting, delays, and getting absolutely nowhere.

https://t.co/y96jeWznSa

[Circle @circle]

An absurd event about a very bored room at Boream & Boredley. Don’t expect anything interesting.

June 9.

https://t.co/fIKOKOjpe7

[Arc @arc]

Arc Moves Fast. This Does Not.

Watch what Arc was built to leave behind.

June 9.

https://t.co/G2L20rZHfz

[Arc @arc]

Prediction markets become more powerful when they start functioning like real market infrastructure.

That requires predictable costs, credible settlement, multi-currency flexibility, and architecture that can support higher-trust financial and operational use cases.

Arc is built to support that evolution.

[bobbilee | Arc Architects Lead @ Circle @bobbilee]

architects helping architects 🙏🥹

[Canteen @thecanteenapp]

And now we're live!! 🖼️🖼️🖼️

https://t.co/YSn3gR5u26

[amie 💜 @amiexbt]

something that started as a hackathon idea is slowly turning into a real product that traders will rely on for market intelligence.

seeing Precall predict PSG to lift the trophy and watching it happen feels good, not because we got the call right, but because it validates the direction we’re building toward.

circle agent stack is the brain behind this
product and I wouldn’t stop to appreciate the team @samconnerone @bobbilee and @thecanteenapp for helping us think through this direction

our goal is to keep optimizing the product to at least 75% success rate.

more works and upgrades going

[Arc @arc]

Building prediction markets gets harder when the infrastructure underneath is fragmented.

Arc is designed to give developers a more usable foundation:
→ Gas paid in stablecoins like USDC
→ Multi-currency market creation and settlement
→ Deterministic finality
→ Built to support compliance with auditability and opt-in privacy

If you’re building prediction markets for real-world use cases, build on Arc.

[bobbilee | Arc Architects Lead @ Circle @bobbilee]

give a warm welcome to @CarbzXBT …i am so happy to onboard her as another local lead in Nigeria. she has been working tirelessly for the @arc community since day one 🙏

[CARBZ @CarbzXBT]

I'm excited to share that I've joined Arc as the new Nigeria Local Lead alongside @JerryOjumah

Over the past months, I've enjoyed contributing to the community through educational content, ecosystem support, and helping shine a light on the work being built across Arc

As Local Lead, I'll continue doing what I love most: supporting community members, welcoming newcomers, highlighting builders, and helping more people across Nigeria discover opportunities within the Arc ecosystem

Thanks to all the team at Arc who made this possible and who have been keeping things running @bobbilee, @samconnerone, @silencexlm, @0xmikef
I'm grateful for the opportunity and excited for what's ahead. Happy to do this with the current existing leaders and the more to come ☺️

If you're building, creating, researching, or simply exploring Arc, my DMs are always open. Let's keep growing Arc together 🥂

[Panchu @Panchu2605]

Circle just designed @Arc to be quantum-resistant from the very first block - and most people building onchain haven't fully processed what that means.

Every wallet, every transaction, every smart contract on every EVM chain today is secured by elliptic curve cryptography. Shor's algorithm, running on a sufficiently powerful quantum computer, breaks all of it.

The threat isn't waiting for Q-Day to start. Harvest-now, decrypt-later is already live. Adversaries collect encrypted onchain data today and hold it until quantum hardware catches up. Every public key ever exposed on any chain is already in that exposure window.

NIST finalized the post-quantum standards in August 2024 - ML-KEM (FIPS 203), ML-DSA (FIPS 204), SLH-DSA (FIPS 205). The industry migration deadline is 2030. The clock is running.

What @circle built into Arc is the only answer that makes architectural sense: quantum-secure signatures live at mainnet launch, from block one. Not retrofitted. Not a future hard fork. ML-DSA, CRYSTALS-Dilithium, Falcon - built in from genesis, opt-in, no forced migration, no network reset.

The rollout covers the full stack. Wallet signatures at launch. Private VM layer next - confidential transfers shielded, public keys wrapped in symmetric encryption. Then infrastructure: TLS 1.3 with X25519MLKEM768 hybrid key exchange, HSMs upgraded. Finally validator authentication - moved only after performance testing confirms sub-second finality holds.

Wrote a full breakdown in the Arc House India chapter - why this architecture matters, what the real tradeoffs are, and why this is directly relevant to anyone building payment infrastructure in India right now.

https://t.co/91QJbhEuop

[Rachel Mayer @0xrachelita]

Architects show up

[silence @silencexlm]

Just posted about @Circle's Post-Quantum Security Roadmap explores how @Arc is approaching post-quantum resilience in phases, including:
Quantum-secure signature support in beta at mainnet launch
Quantum-secure private EVM state shortly after mainnet launch

https://t.co/rT4Brv6Jjs

[Arc @arc]

@0xrachelita 🤝