Sui Permanent Testnet

Details

Core Network

• Dynamic validator set: Validator candidates that meet sufficient stake requirements can join the network at epoch boundaries, and active validators can leave the network at epoch boundaries. This validator access model proves what it means to be permissionless.
• Protocol software and Sui framework upgrade support: Unlike Devnet, Testnet will not be wiped on each software update (unless there are extenuating circumstances). The community will be notified appropriately ahead of any planned software updates or data wipes on Testnet. 
• Full node restore from database snapshot: Instead of waiting for a Full node to sync, node operators can leverage a checkpoint to quickly bring up a Full node.   
• Addresses and signature updates: Account addresses, object IDs, and transaction IDs have been upgraded from 20 bytes to 32 bytes to prevent hash collisions. Additionally, Sui’s default hash function is now Blake2b rather than SHA3, as it is far more performant. And in order to support a wide range of transaction sizes, signatures are now applied over hash digests instead of serialized BCS data. This enables Sui compatibility with hardware wallets, whose signer APIs typically allow limited size inputs.

Developer Experience

In keeping with its aspirations for Sui to be a best-in-breed developer platform, the team views this milestone as the earliest incarnation of what iscalled Sui DevX 1.0, where a number of core developer primitives and semantics are brought together:

• the culmination of developer and builder feedback throughout the Sui journey thus far
• foundation elements upon which Sui’s developer ergonomics and developer efficiency will continue to be refined
• designed with intent to enable a Sui ecosystem that is decentralized but not fragmented

These primitives are:

• Programmable Transaction Blocks: This powerful construct enables chaining together a series of transactions–splitCoin, mergeCoins, transferObjects, moveCall, makeMoveVec, publish–to create a custom, atomic transaction block uniquely suited to your application needs. Since moveCall can specify any existing on-chain functionality, Programmable Transaction Blocks essentially provide ad-hoc transaction composition, significantly enhancing the versatility of the Sui Move programming model. 
  Programmable Transaction Blocks also simplify gas coin management, as an application can pass in a vector of gas coin objects and perform coin split/merge within a Programmable Transaction Block, rather than having to perform coin selection before submission.  
• Sponsored Transactions and gas station: While support for sponsored transactions has been in place since release 0.27, Sui announced Shinami’s gas station (guide, API), which is now available for use with Sui’s Permanent Testnet! 
• Object Display Standard: This standardizes off-chain display of objects of the same type using a set of named templates. Sui Explorer and Sui Wallet both support the Object Display Standard now. Sui APIs and Typescript/Rust SDKs also support the Object Display Standard. This was a collaborative effort with lots of ideas and brainstorming from the Sui Community–we would especially like to thank Capsules and OriginByte and for their input to this standard.
• Kiosk Standard: Kiosk, a powerful new primitive, supports listing an object for sale and enforcing creator-defined royalty policies when the object is sold. The combination of Object Display and Kiosk fill two key gaps for folks building collectibles and trading platforms on Sui. We encourage ecosystem wallets, explorers, and marketplaces to explore both the Object Display Standard and the Kiosk Standard for seamless compatibility across the ecosystem. 
• RPC Revamp: There are now more aggregation-based RPC get* methods: getEpoch, getNetworkMetrics, getMoveCallMetrics, queryObjects. JSON RPC batched requests were deprecated in favor of MultiGet* methods. System events were deprecated in favor of dedicated fields in the transaction response. And lastly, a number of legacy RPC methods (marked with unsafe_*) were deprecated in favor of Programmable Transaction Blocks.
• Zero Knowledge Proofs: There is now Move API support for verifying Groth16 ZKP using both BN254 elliptic curve and BLS12-381 (two of the most widely-used curves). This provides for computation proofs in Sui smart contracts and enables privacy-preserving applications.
• Two Granularity of Timestamps: A fine-grained Clock module that supports 2-3 second granularity for near real-time applications, and a coarse-grained Epoch Timestamps.  
• Move Package Upgrade: This is an essential functionality for developers to update their Move contract and to pull in upgrades of dependent packages. Move Package Upgrade will be available on Testnet with the next software update (tentatively planned for first week of April).

Links

• Website
• Developer Portal
• Move Programming Language
• Sui Whitepaper
• Community Forums