Andres Lozano@andyanalog

Sentinel is a developer-first trust layer for APIs. Every incoming request is fingerprinted from its IP, ASN, user-agent, and behavioral signals then scored 0–100 across cadence, endpoint diversity, error rate, IP reputation, and cross-operator history. The score maps to one of three verdicts (ALLOW, CHALLENGE, BLOCK) and your application decides what to do: serve the request, route to a captcha, or drop it. What makes Sentinel different from existing bot-detection products is that the reputation is portable and verifiable. Every fingerprint I evaluate has its score batched and written to a smart contract on Arc L1, our ReputationLedger. When a different operator on the network later sees the same fingerprint, the prior is read back from chain and weighted as the heaviest signal so a credential-stuffing botnet flagged on one customer's login endpoint is pre-blocked when it hits the next customer's signup form. A solo founder integrating Sentinel on day one inherits the same signal quality as a funded company that's been integrated for a year. Billing is built on Circle's USDC on Arc, using a Circle Nanopayments / x402-style settlement model. Each evaluation debits a fraction of a cent from the operator's pool balance. Debits are queued in-process and batched into a single onchain transaction, so per-call gas amortizes to near zero. There are no monthly minimums, no invoices, the contract balance is the bill, and every debit is publicly auditable on Arc's block explorer. Operators can fund their pool through a Circle Developer-Controlled Wallet, which is what makes the whole flow programmable and walletless from the integrator's perspective. Integration is one line: app.use(sentinel({ apiKey })) for Express, Fastify, or Hono. The SDK calls the Sentinel API per request, attaches the verdict to the request object, and short-circuits with a 429 on BLOCK. No infra to operate, no model to retrain, no enterprise sales cycle.

ArcAgent is a conversational AI financial assistant built for WhatsApp, designed to make digital payments as natural as chatting. Powered by Arc and Circle, it enables users to send, receive, and manage USDC transactions directly within a familiar messaging interface — no app switching or complexity. Users simply chat with ArcAgent to perform transactions like “Send 10 USDC to Emma,” with optional voice commands powered by Eleven Labs for hands-free payments. The system includes multi-layered security, PIN protection, and encrypted storage for wallet credentials. ArcAgent also introduces smart features like split payments for group expenses, instant transfer confirmations, and automated receipts for every transaction. Built by a team of engineers and designers, ArcAgent aims to redefine how people interact with money by merging the power of conversational AI, blockchain technology, and digital identity. The project leverages Arc’s infrastructure for instant and secure USDC transfers while providing a seamless, human-centered experience inside WhatsApp Business. ArcAgent bridges fintech and conversational AI. Just Chat. Command. and Pay.

In this hybrid hackathon powered by Arc and Circle, developers will build the next generation of Agentic economic applications using Circle’s Nanopayments infrastructure with settlement on Arc in USDC. For the first time, high-frequency, usage-based transactions between users, APIs, and AI agents can operate without gas overhead eroding margin. Arc provides stablecoin-native settlement with predictable, dollar-denominated USDC fees and deterministic, sub-second finality — enabling real-time coordination and economically viable per-action pricing at scale. 📅 April 20 – 26, 2026 • Apr 20 – 25 (Online): Submit projects by Apr 25. • Apr 25 (On-site Build – SF, CA): Teams refine projects. • Apr 26 (On-site Demos & Awards – SF, CA): Live pitches & winners announced. Get guidance from Arc and Circle experts through on-site support. 📍 On-site Venue (April 25-26): MindsDB SF AI Collective 3154 17th St, San Francisco, California, USA 🤝 Go solo or team up, it's your flow. 🏆 Compete for a $15,000+ Prize Pool. 📍 Please note: If approved for the on-site experience, you’ll also have the opportunity to showcase your project live. Travel and accommodation will not be covered. 🧑🏻‍💻 Secure your spot now – sign up before the Kick-Off Stream!

In this hybrid hackathon powered by Arc, developers will build the next generation of payment systems using AI + Arc with USDC. Explore a world where AI agents can understand natural language, automate financial actions, and move money with precision. From DeFi to digital content and real-world assets, this is your chance to shape the future of intelligent finance. 📅 October 27 – November 9, 2025 • Oct 27 – Nov 8 (Online Phase) – Collaborate and build with developers and AI innovators from around the world. All projects must be submitted by end of day on November 8. • Nov 8 (New York City – On-site Build Day) – Selected participants will be invited to an exclusive in-person session to refine their projects and connect directly. • Nov 9 (New York City – Live pitching & Awards) – Live pitching sessions to a panel of judges and investors, followed by the official winner announcement. 📍 On-site Venue (Nov 8–9): Babe Ruth Room, Jay Conference Chelsea 159 West 25th Street, New York City, USA 🧠 Get guidance from blockchain and AI experts throughout the event. 🤝 Go solo or team up — it's your flow. 🏆Compete for $10,000 in USDC prizes. 📍 On-site participation is by invitation only. Travel and accommodation expenses will not be covered. 🧑🏻‍💻 Secure your spot now — sign up before the Kick-Off Stream!