Polymesh Chain Changelog - v8.0 to v8.1.2

This is the entry point for the Polymesh v8.0 → v8.1.2 runtime changelog. spec_version moves from 8_000_020 to 8_001_020, and transaction_version stays at 8.

The release is dominated by one theme: making Polymesh assets usable from EVM code without giving up compliance. v8.1 exposed fungible assets as ERC-20 tokens; v8.1.1 completes that surface with ERC-3643 and ERC-7943 coverage, adds an ERC-721 precompile for NFT collections, and adds a general-purpose runtime precompile for the calls that are not scoped to an asset. Supporting that work, the chain gains holder-level asset freezing, NFT approvals, and first-class support for ETH wallets in the Relayer and MultiSig pallets.

Baseline

The "v8.0" side of this comparison is chain v8.0.2 (spec_version 8_000_020), the last v8.0.x patch release. If you are still on v8.0.0 or v8.0.1, see the note on patch releases below.

v8.1.0 and v8.1.1 were Testnet and Develop releases. Mainnet's first v8.1.x runtime is v8.1.2, so it upgrades from v8.0.x in a single step and this changelog is written as one v8.0.2 → v8.1.2 upgrade. If you operate against Testnet or Develop and already ran v8.1.1, read What changed in v8.1.2 instead — it is the delta you need, and the rest of this section will be familiar.

Who this is for

• Smart contract developers, EVM tooling and wallet integrators — three precompiles are now available. Start with Fungible Asset Precompile, NFT Precompile, and Polymesh Runtime Precompile, then the Precompiles reference for how to use them.
• Asset issuers and their agents — Asset Freezing is new capability you can use immediately: freeze an individual holder, or part of a holder's balance, rather than the whole asset. NFT issuers should also read NFT Approvals.
• Exchanges, custodians, indexers — this release changes the pallet API, unlike v8.1. New extrinsics, events, errors and storage items exist, and two storage migrations run at the upgrade. See Full Pallet API Reference, and note the new Asset and Nft events your indexer will start seeing.
• Wallet and SDK integrators — ETH Wallets covers EVM-keyed accounts as subsidy beneficiaries and MultiSig signers, and the restriction of transaction tipping to Governance Committee members.
• Node and infrastructure operators — Other Runtime Changes for the storage migrations, the Grandpa warp-sync fix, and the refreshed weights.
• Anyone already running v8.1.1 on Testnet, Develop or a private network — What changed in v8.1.2 is the short list of what v8.1.2 corrects on top of it.

Key themes

Precompiles

v8.0 added pallet-revive, giving Polymesh a dual-VM contract engine. v8.1 and v8.1.1 use it to expose native chain functionality to contracts through three precompiles:

Precompile	Address	Interface	Covers
Fungible Asset	0x<assetId>00080000	ERC-20, partial ERC-3643 and ERC-7943	Every fungible asset
Non-Fungible Asset	0x<assetId>00090000	ERC-721, ERC-721Metadata, ERC-165, partial ERC-7943	Every NFT collection
Polymesh Runtime	0x…0000ffff0000	IPolymeshRuntime	Asset creation, ticker registration, DID onboarding, agent authorization

Every asset and every collection is exposed automatically — there is no deployment step, no registry, and no issuer opt-in. Calls route through the same pallet code an extrinsic would, so identity, compliance, transfer restrictions and agent permissions are enforced exactly as before. A call that would break a Polymesh rule reverts rather than silently succeeding.

The practical consequence for a contract developer is that a Polymesh asset behaves like a standard token until a rule says otherwise. Both asset precompiles deviate from their standards in ways mainstream tooling does not expect, and each precompile page documents those deviations in full. Read them before porting an existing integration.

ERC-3643 and ERC-7943 methods

The fungible-asset precompile gains much of the permissioned-token surface that ERC-3643 (T-REX) and ERC-7943 (uRWA) define: pause/unpause, setName/setSymbol, isAgent, setAddressFrozen, freezePartialTokens/unfreezePartialTokens, setFrozenTokens/getFrozenTokens, and canSend/canReceive. This lets tooling written for regulated-asset standards work against Polymesh assets with less Polymesh-specific code. Neither standard is implemented in full — the fungible-asset reference records what is implemented and where it deviates.

forcedTransfer now delivers to a named recipient rather than to the caller, on both the fungible and NFT precompiles. See Fungible Asset Precompile.

Holder-level asset freezing

Before this release, freezing was all-or-nothing: an agent could freeze an entire asset, stopping every transfer. v8.1.1 adds freezing scoped to a single holder — either an account key or a portfolio — and to part of a holder's balance.

This is the Substrate-side feature with the widest reach: it adds five extrinsics to pallet-asset, new storage in pallet-asset and pallet-portfolio, new transfer-time errors, and new events. Anything that pre-checks whether a transfer will succeed needs to account for it. See Asset Freezing.

NFT approvals

NFTs gain the approval model fungible assets already had: a per-token spender (Nft::approve) and a collection-wide operator (Nft::set_approval_for_all), which together back ERC-721's approve/setApprovalForAll. Settlement::transfer_funds now accepts non-fungible funds in spender mode, consuming an approval. See NFT Approvals.

EVM key support

An EVM-keyed account can now be subsidised by the Relayer pallet — including the storage deposit pre-charged for an EVM transaction — and can act as a MultiSig signer. ETH wallets accepting authorizations do not pay the transaction fee, matching Substrate keys. Separately, transaction tipping is now restricted to Governance Committee members. See ETH Wallets.

Correctness fixes in v8.1.2

v8.1.2 adds no new capability. It closes gaps in the features above and tightens three permission checks:

• Freeze enforcement now reaches the pre-flight reports. In v8.1.1 a transfer report could come back clean for a transfer the chain would then reject because the sender was frozen. Both the fungible and NFT reports now evaluate the holder freeze and the frozen balance, so the report and the transfer agree.
• Freezing now covers every route out of a portfolio. Portfolio-to-portfolio moves check the frozen balance, not just a whole-portfolio freeze; launching an STO and funding a capital distribution now check the freeze too; and an NFT held in a frozen portfolio can no longer be locked into an instruction.
• Sto::invest no longer assumes its settlement completed. When the offering asset — or the raising asset, for an investment funded on chain — had mandatory mediators, invest debited the fundraiser's tiers even though the instruction was still pending affirmation.
• Three permission checks tightened: secondary keys need portfolio permission to quit custody, MultiSig::create_multisig validates the permissions it is given, and Except extrinsic permissions are now refused wherever they are still accepted.

See What changed in v8.1.2 for the detail.

Migration checklist

Unlike v8.1, this release changes the pallet API. Work through the list below:

1. Re-generate metadata-derived code. New extrinsics, events, errors and storage items exist across pallet-asset, pallet-nft, pallet-portfolio and pallet-settlement. transaction_version is unchanged at 8, so existing signing code is unaffected, but decoding and type generation should be refreshed against v8.1.2 metadata. See Full Pallet API Reference.
2. Update transfer pre-checks for holder freezing. A transfer can now fail because the sender or their portfolio is frozen for that asset, or because the amount exceeds their unfrozen balance — with errors that did not exist in v8.0. The pre-flight reports account for both as of v8.1.2, so a clean report is again a reliable signal. See Asset Freezing.
3. Handle the new events if you index chain state: Asset::FrozenBalanceSet, Asset::SetAccountFreeze, Asset::ControllerTransferTo, Nft::NFTApproval, Nft::NFTApprovalForAll, Nft::NFTApprovalSpent.
4. Settlement::AllowancesNotSupportedForNFTs is renamed, not removed — it is now DeprecatedAllowancesNotSupportedForNFTs and keeps its index, so decoders keyed on the index still resolve. NFT spender transfers now fail with Nft::InsufficientNFTApproval instead. Update any error-name matching.
5. Two storage migrations run at the upgrade, backfilling NFT counts. No action is required, but node operators should expect the upgrade block to do proportionally more work on chains with many NFTs. See Other Runtime Changes.
6. If you use NFTApi, note it is now at version 4 with two added methods. Version 3 clients continue to work.
7. If your secondary keys call into the EVM, permission checks now evaluate the extrinsic actually being dispatched rather than the pallet-revive call carrying it. A secondary key that could previously make a precompile call may now need permission for the underlying extrinsic. See Other Runtime Changes.
8. If you submit tips, only Governance Committee members can now do so. DID Registrars have lost that ability. See ETH Wallets.
9. If you build EVM contracts or tooling, read the precompile pages and the Precompiles reference before writing code.
10. If you create external agent groups or secondary keys programmatically, stop emitting Except extrinsic permissions. They are refused at both the pallet and the extrinsic level — build the equivalent These set instead. See What changed in v8.1.2.
11. If you run an STO, handle the new Sto::InstructionNotSettled error. An offering asset with mandatory mediators makes every Sto::invest fail with it, and a raising asset with mandatory mediators does the same for every investment funded on chain, because the investment instruction cannot settle within the call. See What changed in v8.1.2.
12. Re-estimate fees. Weights were re-benchmarked across pallet-asset, pallet-nft, pallet-portfolio and pallet-settlement. Nft::redeem_nft and MultiSig::create_multisig also changed how their weight is derived. See Other Runtime Changes.

A note on the v8.0.x patch releases

The v7.4 → v8.0 changelog documents the v8 runtime as deployed, which is spec_version 8_000_010 (v8.0.1) and later — not the initial v8.0.0 tag. Two patch releases followed v8.0.0:

• v8.0.1 (8_000_010) — removed the legacy Contracts/PolymeshContracts (Wasm/ink!) pallets, moved to Substrate stable2603-4, plus runtime fixes (secondary-key permission check in transfer_funds, blocking transfers of frozen assets, a same-DID check in unverified_transfer_asset, an automatic-payout fix) and corrected benchmark weights. All of this is already reflected in the v7.4 → v8.0 changelog.
• v8.0.2 (8_000_020) — CI and Docker packaging changes only; no runtime logic change.

This changelog picks up from v8.0.2.