How to monitor a proxy contract for upgrades (Upgraded, AdminChanged, ownership)

Get alerted when an ERC-1967 / UUPS / transparent proxy is upgraded, its admin changes, ownership is transferred, or it is paused. Works for any contract you depend on.

If your funds sit in an upgradeable contract (most DeFi, bridges, many tokens), whoever controls the upgrade can change its code. Watching the upgrade events tells you when that happened.

Standard events

• Upgraded(address implementation) (ERC-1967), topic0 0xbc7cd75a20ee27fd9adebab32041f755214dbc6bffa90cc0225b39da2e5c2d3b, emitted by the proxy.
• AdminChanged(address,address) and BeaconUpgraded(address) (ERC-1967).
• OwnershipTransferred(address,address) and OwnershipTransferStarted (OpenZeppelin Ownable / Ownable2Step).
• RoleGranted, RoleRevoked, RoleAdminChanged (AccessControl), Paused/Unpaused.
• Timelock CallScheduled/CallExecuted/Cancelled: watching the timelock gives you the delay window before an upgrade executes.

Tip: for a transparent proxy the Upgraded event comes from the proxy address, not the ProxyAdmin. Watch the proxy, and also the ProxyAdmin or timelock that owns it.

Doing it with Ledgerbell (free tier)

1. Open the Ledgerbell dashboard and click Create a new key (no signup, no email; save the key).
2. Pick the chain (Base, Ethereum, Arbitrum One or OP Mainnet), type Contract / Safe admin, paste the address.
3. Paste a webhook URL (Discord, Slack, Telegram bot, ntfy or any JSON endpoint) and click Add watch. Use test to send a sample message.

Free: 3 watches and 50 alerts/day, polled about once a minute. Pro (30 watches, 1,000 alerts/day) is 5 USDC on Base per 30 days. Or use the API:

curl -s -X POST https://ledgerbell.quietworklabs.workers.dev/api/key
curl -s -X POST https://ledgerbell.quietworklabs.workers.dev/api/watch -H 'content-type: application/json' -H 'x-api-key: lb_...' \
  -d '{"chain":"base","kind":"contract","address":"0x...","webhook":"https://ntfy.sh/your-long-random-topic"}'