Webassembly-backed modules

[KaiserKarel]

Synopsis

Using web assembly for business logic makes union easier upgradeable, as we do not require hard forks to upgrade the network.

Introduction

Introducing or altering new modules means the network necessarily must hard fork, which is a time-consuming and complicated operation. Cosmos chains often break in the process, and joining the network and bootstrapping (synchronizing from block 0), means you need to have access to all historic binaries.

Instead, I propose a module that wraps wasmd, and shells out actual business logic to wasm. This would allow the network to dynamically upgrade the modules by replacing the backing wasm.

Implementations

The go cosmos module would map wasm blobs to module ids (ModuleId -> blob) and forward sdk.Messages to the module.

The module itself has access to all APIs through a host function interface.

You don't need to meter the blob, as it has the same privileges as a regular module.

We could choose to use the Cosmwasm standard, or a simpler interface with direct host bindings, handling protobuf deserialization inside the blob itself.

Upgrading a blob retains the ModuleId mapping, so existing integrations keep working.

Interblob Calls

The module handles calls between wasm blobs by instantiating multiple VM instances.