Roadmap

Works today

• Front end: lexer, parser, precise diagnostics with a suggested fix.
• Checker: needs against every call, the capability subset rule, secrets, a real type checker (inference, generics, enums with exhaustive match, failure families, refined types).
• Backends: WebAssembly on Wasmtime with host-checked effects, and a WASI module for any runtime.
• Language: floats, enums, records with update, lambdas, defer, tasks, modules with use, a standard library, test blocks.
• Tooling: sub check, explain, manifest, build, run, test, fmt, init, a language server.
• Memory: region collection in the Wasm backend.
• Centcom: sub manifest --centcom and an integration design.

Next

Phase	What
Soon	A fuller self-hosted compiler (only the lexer is written in Subtype), while and break, mutable lists, a Map literal
Soon	Library namespaces (use ... as), private names, a package manager
Soon	Wasmtime for sub test, a policy file for unattended runs
Later	An LLVM or native backend, on purpose after the Wasm path
Later	The whole compiler written in Subtype

Open questions

• How an unattended agent gets its permissions approved, beyond --yes and the .sub-allow list.
• How scripts call tools like git safely, beyond word-by-word run patterns.
• The name and command: language names, trademarks, package names and the sub command should be checked before a public release.