Limitations

This page exists so you do not discover these the hard way. vow 0.1.0 is the first native release.

Language

No garbage collector, and no manual free() — arenas + region { } scopes; the compiler works out when memory is no longer needed. Analysis is intraprocedural and conservative.
No FFI — by design for v1 (FFI would punch a hole in capability-oriented API confinement).
Async runtime ships in 0.1.0 — async fn, await, block_on, thread-pool offload for db_query and files. HTTP handlers in vow-web-server are sync; use block_on inside them. See Async / await.
No SMT contract proving — requires / ensures are runtime checks only.
dyn interfaces ship — static + vtables; see tests/lang/dyn_shapes.vow.
print / eprint are ambient — stdout/stderr via libc with no Caps grant (debug/DX).
Map keys — non-String keys supported in 0.1.0 (map_new<int, String>() etc.).
JSON is opaque JsonValue — parse/stringify ship; deep field accessors are still thin.
No inotify yet — file_mtime is poll-based.
29 libraries + vow-web-server on vpm.vowlang.dev — see Package ecosystem.

Native C compiler at lang/native/ — zero Python under lang/. Install via curl -fsSL https://install.vowlang.dev | sh.
vow fmt, vow lsp, vow new / vow init, vow inspect, vow profile, curl installer, and bundled lld ship in 0.1.0.
vpm native CLI — default registry vpm.vowlang.dev. 30 packages seeded.
VS Code extension vowlang.vow-lang on the Marketplace.
HTTP routing in vow-web-server v0.2.1 — blocking accept by default; runtime emits HTTP/1.1 + keep-alive when the client sends HTTP/1.1 (chunked for bodies ≥ 1MB). listen_async / listen_concurrent are stubs until v0.3.

See /BENCHMARKS.md. Expect losses vs hand-tuned C on some microbenchmarks.