Patract is developing development tools and services for Polkadot’s Wasm contract technology. With the support of Polkadot Treasury, we have completed the development, report, and external review of Himalia and Ask!. However, in the past six to twelve months, the underlying technology of Wasm contracts led by Parity has undergone tremendous breaking changes, so we continued to contribute our developers for long-term maintenance. Among them, the function changes of Pallet-Contracts and ink! mainly include

• Change of Pallet-contracts
  • Refactors
    • PR#9838 contracts: Refactor dispatchables
    • PR#8604 contracts: Refactor the exec module
    • PR#9669 remove rent contracts: Remove state rent
  • update about host_func
    • PR#10366 Stabilize "seal1" seal_call
    • PR#9609 Contracts pallet - Add support for recovering public key from elliptic curve signatures (ECDSA)
  • update about debug_message
    • PR#9550 Stabilize seal_debug_message
    • PR#9051 seal_debug_message not showing up in process output
  • update about wasm executor
    • PR#10173 Refactor sp-sandbox; make sure both sandbox executors are always tested
    • PR#10268 Forward wasmer-sandbox feature to sp-sandbox
    • PR#5920 Integrate Wasmer into Substrate sandbox environment
• Change of ink!
  • PR#792 Implement seal_debug_message
  • PR#914 Implemented ECDSA recover function.
  • PR#903 Cleanup metadata codegen slightly
  • PR#845 Update to scale-info 1.0, introduce metadata format versioning
  • PR#665 Implement new trait definition codegen rocket
  • PR#997 Use edition 2021

In addition, we paid a lot of cloud server and bandwidth costs for API service Elara. The following is a summary of the maintenance work and cost of each product in the past year:

Himalia (12 months)

Himalia is our Wasm contract multi-language SDK, divided into Go/Python version. More than a year ago, we completed the development of version 0.2. After that, the maintenance work of the Github repo are as follows:

• PatractGo:
  • Submitted 16 Commits.
  • Updated version to support metadata14 format modification
  • Update all test cases to support the latest version of ink!
  • Add erc721 example
  • Add delegator test cases for contract mutual calls
  • Fix other discovered problems
• PatractPy:
  • Added 6 Commits.
  • Updated version to support metadata14 format modification
  • Update all test cases to support the latest version of ink!

The maintenance costs are:

• 1 maintainer * monthly salary $200 * duration 12 months = $2400

Elara for Kusama (12 months), Statemine (7 months), Westend (8 months), Westmint (7 months)

Elara is a node API service similar to Ethereum Infura. By building a middleware service layer, we can provide large number of users to visit by a small number of nodes. More than a year ago, we completed the development of version 0.2. After that, the main maintenance cost is from maintainer and cloud service.

maintenance cost ($74980) :

• 1 maintainer * monthly salary $500 * duration 12 months = $6000
• The total cost of Alibaba Cloud service in Singapore is $68980 (434579 CNY), the details are as follows:
  • The unit price of each service is:
  • Resources and costs actually consumed by each network：
  • This is the screenshot of the Alibaba Cloud bill, the total cost is 805773 CNY, from which the Polkadot/ Statemint services should be paid by the Polkadot Treasury are 204969 CNY, and the Kusama/ Statemine/ Westend/ Westmint services should be paid by the Kusama Treasury are 434579 CNY, the rest are for other community chains.
  • This is the screenshot of the Elara website statistics, total is 97352 GB / 6.06 Billion Requests, from which the traffic for Polkadot/Statemint is 18693 GB, for Kusama/ Statemine/ Westend/ Westmint is 77572 GB, the rest are for other community chains.

Summary (2021)

$2400 (Himalia) + $6000 (Elara maintainer) + $68980 (Elara cloud) = $77380 / Monthly avg price of KSM $330 = 234 KSM