This is an abstraction layer around the wasmer VM to expose just what we need to run cosmwasm contracts in a high-level manner. This is intended both for efficient writing of unit tests, as well as a public API to run contracts in eg. go-cosmwasm. As such it includes all glue code needed for typical actions, like fs caching.
There is a demo file in testdata/contract.wasm - this is a compiled and
optimized version of contracts/hackatom
run through cosmwasm-opt.