💻 Desktop app architecture
ethui is native desktop software (not a browser extension):
✅ Multi-browser support
✅ Survives browser restarts
✅ Better security isolation
✅ Persistent state
Built for developer workflows.
ethui.dev
🔗 Per-website chain connections
Each website connects to its own chain simultaneously:
localhost:3000 → anvil
app.uniswap.org → mainnet fork
testdapp.io → sepolia
All at once. Zero manual switching.
Test multi-chain scenarios properly.
ethui.dev/docs/feature...
🌐 Multi-browser, multi-chain support
ethui connects to Chrome AND Firefox at once.
Different dApps → different chains simultaneously.
Testing cross-chain? One browser on mainnet fork, another on L2.
No profile switching or browser restarts.
ethui.dev/docs/feature...
💻 Local-first development with ethui
Works directly with local anvil:
✅ No cloud dependencies for core dev
✅ Fast feedback loops
✅ Offline-capable
✅ Full environment control
Test and build without internet. Deploy when ready.
ethui.dev
🆔 Unique chain IDs in ethui stacks
Every stack gets its own chain ID for:
✅ Replay attack protection
✅ Easy contract identification
✅ Different logic per testnet
Signatures are chain-specific. Test custom chain logic safely.
Private testnets:
🔐 HD Wallets in ethui
Standard mnemonic multi-address wallets:
✅ BIP39 standard (12/24 words)
✅ scrypt encryption
✅ Password strength enforcement (zxcvbn)
✅ Multiple addresses
For when you need production-grade security beyond plaintext test wallets.
💾 Cloud-persistent anvil with ethui stacks
Your testnet doesn't disappear when you close your laptop:
✅ Share with teammates
✅ Demo to stakeholders
✅ Resume testing anytime
✅ Live documentation
No more "works on my machine" problems.
Persistent testnets:
⚡ Fast mode in ethui: Skip transaction reviews
Traditional flow: Deploy → popup → review → confirm → wait → test
ethui fast mode: Deploy → test
No confirmation friction during development.
Get instant feedback. Focus on building.
ethui.dev/docs/feature...
🔑 Lazy loaded private keys in ethui
No forced password on startup. We only ask when a signature is needed.
Then we cache it securely in-memory (using the secrets crate for isolation) for a few minutes.
Faster workflow. Security when needed.
ethui.dev/docs/feature...
🔮 Transaction simulations in ethui
Using revm (same as forge), ethui simulates transactions locally:
✅ Success/revert preview
✅ Token transfer details
✅ State change validation
Works on local anvil without 3rd-party services like Tenderly.
Debug before you submit.
ethui.dev/docs/feature...
Fork any network with ethui stacks
Test against mainnet protocols without gas costs.
Fork Ethereum mainnet, Sepolia, or any EVM chain. Just provide upstream RPC.
Interact with real Uniswap, Aave, etc. No mock deployments needed.
One-click private testnets: stacks.ethui.dev
Anvil is different from production blockchains
It can override state, mint ETH, impersonate accounts, create snapshots, and revert
These features don't exist in real chains. User-facing wallets aren't built for this.
ethui is built specifically for anvil's testing capabilities
Need a test wallet without password prompts?
ethui supports plaintext wallets that store your test mnemonic without encryption
No password needed. Works with the default anvil mnemonic:
test test test test test test test test test test test junk
Only for test funds. Never use with real assets.
💬 Calling ethui stacks early users - we want feedback:
📊 Use case?
🐛 Bugs?
✨ Feature requests?
🔧 Self-hosting or hosted?
Future work: subgraph support (trickiest part: anvil reverts).
If you have experience with anvil + subgraph, we need your input.
Open source: github.com/ethui/stacks
Tired of juggling inline arrays and tuples when interacting with contracts?
ethui renders dynamic forms based on ABI inputs
Handle complex fields without cramming everything into a single text box. Type "1 ether" and it parses to correct uint256.
Need to interact with contracts during local development?
Most tools: Deploy to testnet, verify source code on etherscan, then interact
ethui: Interact with contracts directly from compilation artifacts
No publishing. No verification. Fully local and private.
What did you ship in January?
New contract deployed? Feature launched? Bug fixed? Contribution merged?
Share what you built this month
ethui's transaction preview is also a transaction editor
Tweak transaction params before submitting and see simulation update in real-time
Test how your transaction reacts to different parameters without submitting multiple times
Edit, simulate, adjust, then submit
🎯 ethui stacks use cases (from a year of use at Subvisual):
1️⃣ Internal QA testing: persistent test environment
2️⃣ User testing: instant wallet funding with anvil_setBalance
3️⃣ Protocol integration: fork mainnet, use real Uniswap/Aave instead of mocks
What's your use case?
Try it: stacks.ethui.dev
🔧 ethui stacks overview:
• Private persistent anvil instance
• Authenticated RPC + private API key
• Unique chain ID (replay protection)
• All cheatcodes: setBalance, impersonate, snapshots
• Fork any EVM chain
• Built-in explorer
Local anvil power, cloud persistence.
Try it: stacks.ethui.dev
ethui detects whether a chain is anvil-based using the anvil_nodeInfo RPC endpoint
When detected, dedicated sync continuously tracks the chain head and correctly identifies:
• New blocks
• Reverts to prior snapshots
• Full restarts
Real-time sync with your anvil development workflow
💡 Testnet problems ethui stacks solves:
❌ Distributing gas to testers
❌ Broken/incompatible mocks (different MockUSDC everywhere)
❌ Slow deploy cycles
❌ Network congestion
✅ anvil_setBalance - instant funding
✅ Fork mainnet - real protocols
✅ Instant rollbacks
stacks.ethui.dev
The testnet pain points (gas distribution, interoperability, and slow feedback) have been solved.
Free to try, open source, self-hostable.
Read the full announcement 👇
ethui.dev/blog/stacks
#EthereumDev #Testnets #DeveloperTools
🚀 Introducing ethui stacks: one-click private testnets
We've been using this internally for the past year. Now it's yours.
Create on-demand Ethereum testnets with: cloud-persistent anvil with unique chain IDs, private API keys, all cheatcodes, fork any network, built-in explorer.
What's in your Ethereum dev stack right now?
Drop your setup below:
• Local node (anvil, hardhat, ganache?)
• Testing tools
• Wallet you're using
• IDE
Curious what other devs are running
Restarted or reverted your anvil chain, and now Metamask won't sign transactions?
Most wallets cache nonces locally. When anvil resets, their cached nonce no longer matches the chain.
ethui calculates nonces from scratch every time
Works correctly with anvil snapshots, reverts, and full restarts
ethui automatically uses anvil_impersonateAccount when submitting transactions to anvil chains
This prevents replay attacks when testing with mainnet chain IDs
No signatures from your private keys. No unlocking wallets.
Security feature that happens to be convenient for development
Most wallets force you to unlock when you first open them
ethui defers password input until a signature is actually needed
Multiple wallets, various types, unlock only when required
Cached in-memory for a few minutes using secure isolation to prevent leaks
What's your main Ethereum dev goal for 2026?
A) Ship my first dapp
B) Contribute to open source
C) Master smart contract security
D) Build multi-chain applications
Vote below and tell us what you're working on 👇
2025 for ethui:
— Improved local dev workflows
— Added simulation features
— Expanded multi-wallet support
— Grew the contributor community
Thanks to everyone who used ethui, filed issues, and contributed code this year.
More coming in 2026!
