“Wasm on the Blockchain: The Lesser Evil” The full rationale, described within the context of requirements for blockchain VMs (secure, deterministic, generic, and efficient).
The Polkadot Network tweet that caught my attention:
https://twitter.com/polkadotnetwork/status/1064550109965373440
Related:: eWASM’s design rationale document https://github.com/ewasm/design/blob/master/rationale.md.