# Build Unchained Apps with Avail I Robin Roy

- Speakers: [Robin Roy](https://streameth.org/speakers/robin-roy)
- Channel: [ETHGlobal](https://streameth.org/ethglobal)
- Date: 2025-11-09
- Duration: 34:01
- Topics: Avail Nexus, unchained apps, intents & solvers, N→1 bridging, cross-chain liquidity, bridgeAndExecute, unified balances, headless SDK, React Widgets, shadcn Elements, exact-in/out swaps, DEX aggregators, EIP-1193 provider, gasless user call, multi-chain (~12), DeFi deposits, payments, ETHGlobal bounties, office hours POAP
- Watch: https://streameth.org/watch/yt-9ah9Q--EiQg
- YouTube: https://www.youtube.com/watch?v=9ah9Q--EiQg

## Description

Robin (Avail) introduces Avail Nexus, a cross-chain interoperability toolkit for building “unchained apps”—deploy once, serve users’ liquidity from anywhere. Instead of forcing users to pre-bridge to a specific chain (poor UX), Nexus aggregates a user’s scattered balances across many chains and fulfills actions via intents + solver networks. This turns many 1→1 bridges into a single N→1 operation (e.g., pull USDC from Base/OP/Arbitrum to deposit on Hyperliquid/Avalanche) and can optionally execute a contract call after funds arrive.

For developers, Nexus provides a headless/core SDK and drop-in UI: React Widgets (ready-made) and customizable shadcn Elements. Core methods: bridge (N→1), transfer (N→1 to recipient), bridgeAndExecute (N→1 + call contract with ABI/params), and cross-chain swaps (exact-in / exact-out via DEX aggregators). You can simulate bridge/execute, fetch unified balances across ~12 mainnet chains, and must initialize with an EIP-1193 wallet provider (e.g., MetaMask, wagmi/RainbowKit). Gas is gasless for the user-side call; speed depends on solver liquidity. ETHGlobal bounties: (1) General unchained apps, (2) DeFi/Payments, (3) Developer feedback (submit feedback.md). Avail runs weekly office hours with POAPs and a merch raffle.

00:10 Intro & goal: “unchained apps”
01:37 Real UX pain: needing exact token on exact chain
03:24 Nexus solves by aggregating user liquidity via intents/solvers
05:23 Why native bridges (secure) and LP bridges (faster) still hurt UX
07:02 Positioning: not “just a bridge”; dev SDK in-app, keep users on your UI
08:59 From 1→1 to N→1 actions; bridge + optional execute
12:28 TAM example: Avalanche vs rest of Web3 liquidity
14:00 SDK (core): bridge, transfer, simulate
15:43 bridgeAndExecute (contract addr, ABI, fn, args)
17:14 Cross-chain swaps (exact-in / exact-out)
18:38 UI options: Widgets (ready) & shadcn Elements (customizable)
19:49 ETHOnline bounties & docs, starter templates, ideas
21:35 Weekly office hours + POAP raffle
24:18 Dev setup: init with wallet provider, get unified balances
29:11 Demo: N→1 deposit + execute (e.g., supply to Aave)
32:58 Q&A: liquidity sources, gas/time, security notes

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _  

💻 ETHOnline 2025
This workshop is specifically for ETHOnline 2025, a 21-day hackathon held October 10 - 31, 2025, bringing together the most skilled web3 developers, designers and product builders from all around the globe for a weekend-long adventure to advance the Ethereum ecosystem!

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _  

✅ Follow Avail
X: https://x.com/AvailProject

✅ Follow ETHGlobal
X: https://x.com/ETHGlobal​
Warpcast: https://warpcast.com/ethglobal
Website: https://ethglobal.com
YouTube: https://www.youtube.com/c/ETHGlobal 

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _  

_Are you interested in Ethereum development and entrepreneurship?_
👉 Sign up for the next ETHGlobal event: https://ethglobal.com/events
🎁 Get exclusive access and perks with ETHGlobal Plus! https://ethglobal.com/plus
📣 Want us to throw an event in your city? Tell us where! https://ethglobal.com/city