Node.js + ethers.js v6

A single example demonstrating the full @fhevm/sdk lifecycle using ethers.js v6: encryption, reading public values, and private decryption.

Prerequisites

• Node.js >= 22
• SDK dependencies installed (npm install in the repo root)

Setup

Optionally provide a wallet private key:

cp .env.local.example .env.local

Without .env.local, a random wallet is used. The full flow still runs but decryption will fail (encrypted values are not on-chain).

Run

npx tsx ./test-run.ts

Notes

• The E2E transport key pair is generated locally and never leaves the client. Only the corresponding public key is shared (embedded in the EIP-712 permit).
• The EIP-712 permit is reusable within its validity window (durationDays). You can decrypt multiple batches of encrypted values without re-signing.
• The Zama Protocol processes decryption requests and returns encrypted shares that only the holder of the transport key pair can decrypt.
• ACL permissions are checked on-chain before decryption. If FHE.allow() was not called for the user + encrypted value pair, decryption will fail.