Grounded in the actual error-producing call sites (endpoint.rs server
side, call_client.rs client side) and the dependency-crate sources read
from the cargo cache (rustls 0.23.41, rustls-pemfile 2.2.0, rcgen 0.13.2,
quinn-proto 0.11.15, rustls-acme 0.12.1).
Decision: single #[non_exhaustive] enum, one variant per failure
category, owned by alknet-tls (not re-exported from core). Six variants:
CertLoad(io::Error), SelfSigned(rcgen::Error), Rustls(rustls::Error),
VerifierBuild(VerifierBuilderError), QuinnWrap(NoInitialCipherSuite)
[quinn-gated], AcmeConfig(String).
Three findings drove single-enum over thin wrapper: (1) for_quinn()
fails with NoInitialCipherSuite, not rustls::Error — a rustls::Error
wrapper cannot represent the for_quinn() failure; (2) rustls_pemfile::Error
is not a std::error::Error (no Display, no Error impl) so #[from] would
not compile — pemfile BufRead APIs return io::Error; (3)
WebPkiServerVerifier::build() returns VerifierBuilderError, not
rustls::Error — a thin wrapper cannot represent empty-CA-root-store as
a first-class failure.
Deliberately NOT variants: ACME EventError/OrderError (stream events,
logged not returned from new); unknown-raw-key fail-closed (handshake-
time rejection at dial time, not a config-construction error —
corrects OQ-63's original framing); provider init (infallible); resolver
construction (infallible).
Each open question lives in its own file under questions/,
named NNN-slug.md (mirroring the ADR convention). This file is the index:
theme-grouped tables for scannability, plus a cross-theme
Deferred / Blocked section that surfaces the
safe-exit deferrals with their blocking conditions inline — so "what's
currently parked and why" is answerable at a glance.
Status values:
open — Needs to be resolved now. Has a clear path to resolution.
resolved — Decided. The resolution is stated cleanly, without caveats about how it could be changed later.
deferred(scope) — Cannot be resolved yet. The information is genuinely
missing — a crate spec, POC result, or use case that doesn't exist yet.
Has a concrete blocking condition. Not a failure — scope management.
deferred(unclear) — Cannot be resolved yet. The pieces exist (decided
in other ADRs, existing types, existing patterns) but the composition
— how they fit together — isn't clear yet. Resolution requires
investigation (work through examples, maybe POC), not waiting. Has a
concrete investigation target and an impacts field. Not a failure —
honest uncertainty in a poorly-defined problem space.
partially resolved — Some aspects decided, others deferred or open.
dissolved — The question was reframed out of existence (e.g., superseded
by an ADR that retires the premise). Kept for reference.
Impacts field: Every unresolved OQ (open, deferred(scope),
deferred(unclear), partially resolved) should have an Impacts
field stating what it blocks downstream. Be specific: "blocks the first
hub deployment because the hub dials workers" not "blocks the hub
crate." This is the triage signal that makes the deferral's urgency
visible.
Door type classifications follow ADR-009 — they describe reversal cost (how expensive it is to undo), not urgency:
One-way door: Reversal requires rewriting significant code or permanently closes a capability. Getting it wrong is expensive — requires ADR before implementation.
Two-way door: Reversal is cheap or additive. Getting it wrong is recoverable — decide, implement, revert if needed.
Door type is separate from whether a decision is made. A two-way door is a decision you make now and can revert later, not a decision to defer. See ADR-009 §"What this framework is NOT."
Should alknet-tls Provide a Client-Side TLS Config Helper?
resolved
one
high
Deferred / Blocked
The safe-exit visibility surface. These questions are parked because the
information needed to resolve them does not exist yet — each has a concrete
blocking condition. They are not failures; they are scope management. See
ADR-009 §"Safe Exit: Deferred Decisions." This section exists so "what's
currently blocking the architect" is answerable at a glance, not by
filtering the tables above.
OQ-09: WASM Target Boundaries
Blocked on: A concrete server-side WASM use case, or a deliberate confirmation that WASM stays a client-side design constraint. Tracked as architecture/oq-09-wasm-server-use-case in tasks/architecture/.
Priority: low
Amendment (2026-07-09): The Connection door is now open via Connection::from_stream (ADR-065) — a Connection can be constructed from any wasm-compatible stream. What remains closed is the accept-loop runtime (tokio::spawn does not run on WASM; PendingRequestMap/CallAdapter use tokio channels). The blocking condition (a concrete server-side WASM use case) is unchanged.
OQ-10: Git Adapter Scope — Smart Protocol Only or Full Server?
Blocked on: Speccing the alknet-git crate — resolve this when that crate is specified, not deferred past it. Tracked as architecture/oq-10-git-adapter-spec in tasks/architecture/.
Blocked on: A handler that needs stream operators and finds the existing combinators (Box::pin(stream::iter(...)), async_stream::stream!, futures::stream) insufficient. The operators library is a convenience, not a prerequisite for any handler.
Blocked on: a concrete use case for network or volume management over the call protocol. Dev containers use the default bridge network; hosted services declare networks/volumes in docker compose.
Blocked on: v1 implementation — the create input JSON Schema is finalized when register_docker_ops is written and tested against bollard's Config struct. An architectural decision (ADR-060 §5), not a deferral past implementation.
Blocked on: a second transport's real dial existing (not just a
second QUIC dial). The dial is transport-specific (QUIC, HTTP, TCP+TLS,
WebTransport, raw TCP); we have one shape implemented (QUIC —
CallClient::connect and ChannelClient::connect_quic). Extracting a
QUIC-shaped connector now would bake QUIC in as the establishment
shape — the same welding ADR-065 unwound on the server side. The blocking
condition is met when a non-QUIC dial (SSH raw-TCP, HTTP-wrapped call,
TCP+TLS) exists, so the transport-polymorphic dial+TLS seam is
extractable from two different transport implementations. Note: the
client APIs are already transport-agnostic — CallClient::spawn_dispatch
and ChannelClient::from_connection (ADR-080) take a pre-established
Connection. What is deferred is the shared dial, not the client
protocol surface.
Blocked on: a real deployment observes head-of-line blocking on a
saturated channel where the bounded-buffer's stop-reading mitigation is
insufficient (e.g., a high-throughput file transfer over a tunnel that
saturates a channel and causes frequent demux stalls affecting other
channels). The intended use cases (TTY, SSH, tunnels) are not
high-throughput in the HOL-blocking sense; the trigger requires a
high-throughput use case.
Blocked on: a second two-pump handler existing (the tunnel handler is
the first; SSH direct-tcpip will be the second), so the shape
convergence is observable. Extracting the helper from one consumer would
bake in a shape that the second might not fit. The shutdown-on-completion
contract is decided (ADR-078); only the helper extraction is deferred.
OQ-64: Should alknet-tls Provide a Client-Side TLS Config Helper?
Resolved (ADR-087): alknet-tls provides TlsClientConfig. Not
blocked on the dial-seam extraction (OQ-55) — the TLS config is a
prerequisite for the dial, not a consequence of it. The circular
hedge (TLS config deferred behind the dial, dial needs the TLS
config) is broken. The hub-as-client requirement makes it a
prerequisite for the first hub deployment. See
ADR-087 and
OQ-64.
glm-5.2
43b8179304