Ledger LandISSUE #35 of 90

proxy patterns · transparent · uups · diamond

BlockyVSDouble-Spend Dan

Blocky saysProxy patterns enable upgrades by separating a stable address from swappable logic.

The common trick: a proxy contract holds the state and a fixed address, and delegatecalls to a separate logic contract you can swap. Variants: Transparent proxy, UUPS (upgrade logic lives in the implementation), and the Diamond standard (many logic facets). Upgrades introduce risk (storage-layout clashes, malicious upgrades), so they're guarded by governance/timelocks.

Power-ups you unlock

Proxy = stable address + state; logic is swappable
delegatecall runs logic in the proxy’s context
Patterns: Transparent, UUPS, Diamond
Guarded by governance/timelocks

Double-Spend Dan attacks — common mistakes

Storage-layout collisions across upgrades
Unprotected upgrade function (takeover risk)
Over-engineering upgrades for a simple contract

Boss battleExplain how a proxy keeps the same address while changing logic.

Example code

<!doctype html><html><head><meta charset="utf-8"></head>
<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre>users → PROXY (state, fixed address)
           → delegatecall → LOGIC v1 → v2 (swappable)
guarded by governance + timelock</pre></body></html>

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