> For the complete documentation index, see [llms.txt](https://docs.zama.org/protocol/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zama.org/protocol/sdk/changelog/legacy/v2.md). # 2.x Plain-language release notes for the `2.x` line — what changed in each minor version, in plain terms. This complements the auto-generated [`CHANGELOG.md`](https://github.com/zama-ai/sdk/blob/main/CHANGELOG.md) (the full commit-level list). The `2.x` line is superseded by `3.x` — to move an app forward, follow the [migration guide](/protocol/sdk/migration/migrate-v2-to-v3.md). Notes are written in the API vocabulary of the time (`handles`, `keypairTTL`, `WrappersRegistry`, `ReadonlyToken`, `sdk.publicDecrypt`, …); many of those names changed in `3.x`. ## 2.5.0 *Released 2026-04-17.* This release rounds out the decryption surface and keeps pace with upgraded on-chain wrapper contracts. * **Public-decrypt primitive.** `sdk.publicDecrypt()` is now the primitive for decrypting publicly-decryptable values — no permit signature needed. * **Richer decrypt events.** Decrypt events now expose the decrypted handles and result fields directly. * **Upgraded unwrap events.** The SDK reads the upgraded unwrap events emitted by the wrapper contracts. * **Inferred total supply.** Added a total-supply contract builder that infers the right read for a token. * **Fixes.** Centralized `ZERO_HANDLE` with consistent `isZeroHandle` checks, and aligned the example apps with scoped `isAllowed` checks. ## 2.4.0 *Released 2026-04-13.* The headline here is a smoother decrypt experience in React, plus some trimming of the token surface. * **Unified `useUserDecrypt`.** The React hook now uses a reactive cache and auto-decrypts, so decrypted values stay in sync without manual plumbing. * **Slimmer token API.** Removed bespoke fee and admin features that were tied to a specific integration, keeping the token surface generic. * **`keypairTTL` cap.** The decrypt key pair TTL is now capped at the FHEVM 365-day maximum. * **Examples.** The Node ethers and Node viem examples were upgraded to the 2.x API with full ERC-7984 flows. ## 2.3.0 *Released 2026-04-07.* Delegation and safety checks are the focus. * **Delegation API alignment.** The delegation API was aligned with the Delegated User Decryption spec. * **Balance validation.** Transfers, shields, and unshields now validate balances before submitting, so obviously-doomed operations fail early. * **TTL default.** The `keypairTTL` default was aligned with the session TTL (30 days). * **Quality.** Improved error handling and code quality, plus new Node + Web end-to-end test infrastructure. ## 2.2.0 *Released 2026-03-30.* This release introduces on-chain wrapper discovery. * **Wrappers registry.** Added a `WrappersRegistry` class and matching on-chain registry hooks, so an app can look up the confidential wrapper registered for an ERC-20 (and vice versa) on-chain. * **Delegation robustness.** Added `DelegationNotPropagatedError` to surface the gateway sync delay after a delegation is set. * **Hook naming.** Renamed `useAllowTokens` / `useRevokeTokens` back to `useAllow` / `useRevoke`, and improved the query-wrapper types. * **Examples.** Several example apps were upgraded to the current SDK with full ERC-7984 and delegation flows (wagmi v3, react-ethers, react-viem, and Hoodi). ## 2.1.0 *Released 2026-03-24.* A small maintenance release — this one is thin on library-facing changes. * **Fixes.** Excluded the logger from the web-worker init payload, gated queries on an undefined `tokenAddress`, and colocated the Node worker with the Node entry point. * **Examples.** The Hoodi example gained on-chain ACL delegation flows. ## 2.0.0 *Released 2026-03-20.* The `2.0.0` major bump adds delegated decryption and firms up key persistence and worker reliability. {% hint style="danger" %} **Breaking change: `useUserDecrypt` signature change.** The `useUserDecryptFlow` hook was removed, and `useUserDecrypt` now takes the flow hook's signature. The old low-level `useUserDecrypt` that accepted `UserDecryptParams` is gone. {% endhint %} * **Delegated decryption.** Added support for delegated decryption — letting another account decrypt your values. * **Key persistence.** The FHE public key and params are now persisted with artifact-level revalidation, avoiding redundant refetches. * **Worker reliability.** Browser-extension environments are auto-detected with a file-based worker fallback, worker creation is lazy (via a blob URL) to avoid SSR crashes, and session expiry is detected on the `isAllowed` query. * **Smaller bundle.** Bundle size was reduced by inlining slim ABI fragments. * **Examples.** Added `example-hoodi`, an ERC-7984 demo on the Hoodi testnet. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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