ADR-007: Toolchain pins

• Status: Amended (2026-08-28, dual-line)
• Date: 2026-08-28
• Source: #1, issue description, section “Decisions (ADRs, continuing the numbering of the May design doc)”; amendment from #15, issue description, section “6. Decisions (ADR amendments, effective now)”, copied into #1 under “Amendments from the research record”

Context

From the state of the repository recorded in #1 when the decision was taken (verified 2026-08-28):

Holochain 0.7.0 is released; holonix branch main-0.7 is the target. The lock pins main from May, which resolved to a dev build.

Decision

holonix input is github:holochain/holonix/main-0.7. nixpkgs is nixos-25.05 to match system.stateVersion, unless a required module only exists on unstable, in which case the Builder records the reason in the PR and bumps stateVersion consistently.

Consequences

The record states no consequences beyond the decision itself.

Amendments

2026-08-28: the module is dual-line

From #15, section 6:

Root inputs holonix (main-0.7, the default package) and holonix-0_6 (main-0.6, 0.6.3). The module renders the conductor network section from the package version: lib.versionOlder cfg.package.version "0.7" → bootstrap_url + signal_url (0.6, kitsune2/sbd; production defaults taken from edgenode’s conductor-config-0.6.1.template.yaml); otherwise bootstrap_url + relay_url (0.7, Iroh; defaults from holochain --create-config). Option signalUrl stays for 0.6 and is ignored with a warning on 0.7; new option relayUrl. Both lines get a VM smoke test (vmTest, vmTest-0_6) and a hApp test (vmTestWithHapp with Dino Adventure v0.3.0 on 0.7; vmTestWithHapp-0_6 with Kando v0.17.5 or hREA happ-0.4.0-beta on 0.6), all fetched by sha256. Reason: the release train is 0.7 and that is what a community user adopting the module next month should get by default, while every hApp with real content still targets 0.6.x; a module that serves only one line serves nobody in September 2026.

Its context, from #15 section 1: Holochain 0.7.0 was released 2026-07-30 with Iroh over QUIC as the only transport (signal_url must be removed from conductor configs) and no data migration from 0.6.

Later record

• 0.6 network section. #16 found that a 0.6.3 conductor given only bootstrap_url + signal_url refuses to start with network: missing field 'relay_url', so the module renders bootstrap_url + signal_url + relay_url below 0.7 and bootstrap_url + relay_url from 0.7. The review re-derived this from edgenode’s 0.6.1 template. #1 was not amended.
• nixpkgs. #20 moved the root flake, both templates and the example to nixos-26.05, with system.stateVersion = "26.05", because nixos-25.05 reached end of life. #1 was not amended; flake.nix on main pins nixos-26.05.