Reframes the SSH scope around the channel multiplexer as the decomposition
point. Each feature (forwarding, SOCKS5, SFTP) is a channel type or a consumer
of channel types, stacking on the core — each layer functional when built,
none shipped broken. Dissolves the 'massive v1' framing that produced hedging
language proposing non-functional or half-built versions.
Three developments since the initial 2026-06-25 research changed the framing:
(1) WebTransport landed as ADRs 038/040/043, grounding SSH-over-WebTransport
as a constraint (the handler must be source-agnostic about its Connection);
(2) russh's runtime abstraction (russh-util swaps tokio::spawn for
wasm_bindgen_futures on wasm32) means the SSH *client* runs in WASM when fed a
WebTransport BiStream — the browser case is real, not speculative;
(3) the http crate intersection (ALPN-stream-proxy depends on SSH handlers
being source-agnostic) is now visible and specified.
The layered build order (1-4 stream+connection+channels+exec, then 5
forwarding, then 6 SOCKS5, then 7 SFTP) doubles as the configuration surface:
each layer beyond the core is an opt-in channel type, gating on the
default-deny ACL baseline inherited from russh.
Incorporates user clarifications: SOCKS5 and bidirectional port forwarding are
core non-negotiable v1 features (the VPN-like use case + the 3.5k-clones
demand). Adds DP-10 for the bare-TCP SSH listener as a first-class path needed
for future git-over-SSH, with config shape reserved in v1 (off-by-default,
default-deny). Grounds the client/forwarding recommendations in the dispatch
downstream consumer at /workspace/@alkdev/dispatch, which is a textbook russh
SSH client + direct-tcpip forwarder the user wants to replace with this stack.
alknet-ssh now owns both server and client + SOCKS5-server in v1; the SOCKS5
codec may extract to a separate crate later (two-way door).
Phase 0 exploration for alknet-ssh: confirms SSH-over-QUIC-bistream via
tokio::io::join (no custom adapter needed, per reference impl), russh 0.60.2
generic run_stream/connect_stream, and channel-into-bistream multiplexing.
Surfaces 9 decision points for Phase 1: host key sourcing (vault-derived vs
config), channel policy v1 surface, client + SOCKS5 crate split, crypto
backend, auth method coverage, and a stream-handling POC to close russh's
upstream test gap.