fhevm-cross-contract
Cross-Contract Encrypted Handle Passing
Use this skill when your architecture involves more than one contract operating on encrypted values. Every time an encrypted handle crosses a contract boundary, it needs an explicit ACL grant. Forgetting a single grant in a multi-hop flow breaks the chain at the first real ACL boundary.
When To Use
- Contract A computes an encrypted result and Contract B uses it
- Factory contracts deploy new contracts with encrypted initial state
- DeFi composability where encrypted amounts flow through routers, pools, or vaults
- Debugging "handle not accessible" or ACL failures in multi-contract flows
Core Mental Model
An encrypted handle is a capability token with an explicit access list. Passing it to another contract hands over the token but NOT the access. Every hop needs its own ACL grant. Think of it as a permission chain: A grants to B, B computes a new result and grants to C. Each new
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