tractor/ai/tpt-backends
Gud Boi d9a6e2e9b4 Retract the hand-rolled tunnel peeler from plan-03
§3.2 specced a pure fn `_peel_tunnel_segs(proto_names) ->
(bearer_names, tunnel_specs, overlay_names)` to split a maddr at
its tunnel seg. It should never be written: `py-multiaddr` ships
that whole surface already and the plan simply missed it, even
though gh #443's 2nd bullet links the README sections in
question.

Replaced w/ a ⚠️ CORRECTION carrying the verified API table
(`.decapsulate_code(P_WG)` for the bearer, `.split()`/`.join()`
for a seg tail, `.value_for_protocol()` to read a value,
`.encapsulate()` to recompose) plus *why* it works on an infix
`/wg/` seg: the cut is by proto-code, never by matching an addr
value, and the key seg has no addr of its own.

Also,
- adopt `bearer`/`overlay` as the role names throughout, and say
  plainly why not `inner`/`outer` — the call-stack reading of
  "inner" is the exact opposite of the encapsulation one.
- warn that `value_for_protocol('ip4')` on a full tunnelled
  maddr silently yields the *bearer's* host; only call it on a
  peeled sub-maddr.
- note nesting (wg-in-wg) falls out of `.decapsulate_code()`
  cutting at the *last* occurrence, so peel repeatedly rather
  than recursing through a bespoke splitter.
- `mk_maddr()` for `TunnelledAddress` is `.encapsulate()`
  composition, not `str` building.
- README: drop the "degrades to a plain segment split" para,
  since that path is gone — no codec now means one actionable
  raise.

(this patch was generated in some part by `claude-code` using `claude-opus-5` (`anthropic`))
2026-08-17 17:25:20 -04:00
..
00_shared_backend_contract.md Proto-key the unwrapped-addr form in the plans 2026-08-12 20:08:15 -04:00
01_tipc_backend.md Proto-key the unwrapped-addr form in the plans 2026-08-12 20:08:15 -04:00
02_quic_iroh_backend.md Add `QUIC`-via-`iroh` tpt-backend plan 2026-08-12 20:08:15 -04:00
03_wg_tunnel_bindspace.md Retract the hand-rolled tunnel peeler from plan-03 2026-08-17 17:25:20 -04:00
README.md Index the tpt-backend plans w/ a README 2026-08-12 20:08:15 -04:00

README.md

next-gen tractor.ipc transport backend plans

Implementation specs for three prospective .ipc transport backends, written so each can be worked independently (by a different model/provider) without design or lib-selection drift.

Read 00_shared_backend_contract.md first — it is the normative description of what a tractor transport backend is as of main@83b34884 (the backend duck-type, the 10-item registration checklist, the test-harness plumbing, the code-style rules). The three plans assume it and document only their own deltas.

plan issue dep size lands
01 — TIPC #378 none (stdlib) small first
02 — QUIC/iroh #353 iroh (uniffi FFI) large needs a prep PR
03 — wg bindspace #482, #443 pyroute2 medium, 3 layers layer A now

Headline conclusions:

  • TIPC is the cheap win. Verified: trio.SocketStream and trio.SocketListener are address-family agnostic (only SOCK_STREAM + a trio socket), and CPython ships AF_TIPC + 23 TIPC_* constants. So the backend is ~one module of contract boilerplate, zero new deps, and it buys kernel-native service discovery: bind() publishes, connect()-by-name resolves — no registrar in the loop. (modprobe tipc is required; hard-gate everything.)
  • QUICs cost is entirely in two adapters, not in QUIC. The iroh python bindings are uniffi-generated asyncio, but the asyncio dependency is confined to one future-poll callback — a ~40-line trio bridge (TrioToken.run_sync_soon) replaces it. The second cost is that an iroh listener isnt a socket, which needs a small, independently-reviewable prep PR to _server.py/_types.py.
  • WireGuard is not a transport. Its an iface-layer tunnel, so it belongs as a nested bindspace (TunnelledAddress + open_bindspace() @acms) wrapping whatever L4 tpt is in use — which is also what finally implements the long-specd Address.namespace, and what generalizes to veth/vxlan/gre.

Ordering rationale: plan 01 first as the cheap proof the table-registration story generalizes to a genuinely new proto; plan 03 layer A is already deployable-today doc/example work; plan 02 last (and gated on its prep PR). Plans 01 and 02 both want the same Address.rebind_from_sockname gate — whichever lands first ships it.