Idunn/docs/migration.md
Meta Vens 102c129891 Topology publishes never wait: one private-lock exchange primitive
exchange_behind_private_lock (drivers.rs) is the single write primitive for
the projection directory: one nonblocking compare-exchange behind a lock only
Idunn can hold. An absent lock is created O_EXCL 0600; a lock that is not a
regular file, ours, mode 0600 is replaced by a fresh 0600 file renamed over it
(a chmod does not revoke a descriptor another uid already holds); a private
lock is opened as is. The topology driver's mutate and the incident store both
go through it; the blocking compare_exchange_snapshot call, publish_projection_mode
(which published the lock 0644 on a false premise that readers open it) and
incident.rs secure_lock are deleted.

mutate now retries only a lost race; a held lock is Err "the topology
projection is locked by another holder" and a no-op, so no caller records a
digest, evidence or phase for a publish that did not land.

Test helpers: the lock holder is a separate flock process, and run_while_held
counts opens of the lock (inotify), so ANY wait on a held lock fails, not only
one past the 30 s ceiling. Tests reproduce the live default ACL and use
setpriv for the other-uid half.

This commit has not been built; the verify run follows.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
2026-10-01 01:28:05 +02:00

36 KiB

Migrating a target onto the current Idunn

Status as of 2026-09-08 on yggdrasil, verified against systemd:

  • odin is migrated. idunn-odin-25f32a8d...service is active and running release 928da3ef. This is the live Odin; the odin.service unit still present in /etc/systemd/system/ is active with MainPID 0 and owns no process.
  • heimdall is not. It runs under a hand-written heimdall.service; every idunn-heimdall-* unit is inactive or failed.
  • 76 idunn-* units exist on the host; 2 are active.

Odin's deployment transaction is nonetheless stuck in Committing, so Idunn does not consider it admitted even though the candidate it deployed is the process serving traffic. The gate is advance_committing's requirement that the latest Odin observation equal the Ready receipt, which cannot hold for a target whose observer keeps publishing. Deployment succeeded; the bookkeeping did not.

Read the "Correction: Odin is migrated first, not last" section below as an ordering decision. It changed which target goes first; the migration record is this header.

The previous generation was driven by --swarm-profile and a root shell actuator. That invocation is rejected by the installed binary, which is the clearest way to tell which generation a host is running:

$ idunn --swarm-profile yggdrasil-local --store ...
Error: unknown Idunn command "--swarm-profile"

This document is the route from one to the other. It is written per target, because the cutover is per target — there is no flag-day.

What changes, in one paragraph

The old generation kept its target list in Rust (swarm_targets(), removed by 330e4cd) and its actuation in shell (deploy/legacy/). The current generation keeps capability in a recipe inside each target's own repository, and privilege in an operator binding on the host. Idunn seals source, builds in a runner, admits one incarnation, warms a candidate under a distinct UID and namespaces, fences the incumbent, promotes the route, and drains. Nothing in that path takes a command string.

Order

Migrate in dependency order, and migrate the authority's own dependencies last:

  1. codex-connector — do not migrate. Retire it. The operator is not returning to Codex, so a credential-isolated transport for Codex subscription inference has nothing left to isolate. It is already dead in practice: the deployed daemon has been failing every three minutes with 401 ... token_expired against chatgpt.com/backend-api/codex/models, with no established connections on its port. Migrating it would mean writing a binding for a corpse. See Retiring Codex below. 0b. gjallar — do not migrate. Retired 2026-09-06. Had a brief useful life on Nightwing's framebuffer, then broke and was never fixed. The Yggdrasil incarnation ran --headless --refresh-hz 2 for eleven days: a compositor with no display, recomposing twice a second, 55 minutes of CPU and 125 MB resident to produce frames nothing rendered. The only reference to gjallar.overview in the estate is one Odin test file. Stopped and disabled; 420 MB under /srv/gjallar is reclaimable.

  2. heimdall — first. Most release-shaped of what remains, and its one prerequisite follows an existing estate pattern: it takes CultLib from a sibling checkout via file:../CultLib, so it needs a vendor/CultLib gitlink before its source can be sealed. See The first three targets.

  3. repixelizer — second. No CultLib dependency at all, but runs a venv interpreter against a checkout, so it needs an artifact story for Python before a recipe means anything. Unit is repixelizer-gui.

  4. streampixels-service and streampixels-web — migrate as two Idunn targets from one repository. The native Unity renderer runs on each creator's machine; Yggdrasil hosts only the TypeScript API and Next.js web app. Build those two artifacts with the pinned Node runner, preserve Postgres and Redis as external state owners, and admit the service before the web target that consumes its API capability. The repository declares separate recipes at deployment/idunn/service.toml and deployment/idunn/web.toml; each host binding selects one recipe path.

    Retire the old continuity path during cutover. The preview tarball, checkout-based systemd units, and legacy deploy helper are not an alternate recovery lane. The current host's live status and any existing creator data must be inspected before stopping them. Preserve the public host and path routing, with nginx pointing at Idunn's stable service and web endpoints.

  5. ghostlight — blocked, not merely later. A world-elaboration and ontology rebuild is running in it right now: commits landed 2026-09-05 across 178 branches, with work parked on codex/ghostlight-dungeon-mvp. Adding deployment/idunn/recipe.toml to that tree collides with live work. Migrate it when the rebuild lands, and coordinate rather than assuming.

  6. bifrost-persona-feedback — the only target that carries signed-release authority. Migrate it after at least three ref-head targets work, because it is the one that exercises selection = "signed-release".

  7. epiphany and epiphany-capstone-17 — two targets sharing a repository. Prove the binding-per-target model here.

  8. voidbot — deployed, live retrieval path, 5.7 GB of state. Not early.

  9. odin — see the correction below. This entry said "last of the targets"; it is first, and the reason is structural.

  10. Idunn itself — the installed unit and binary. See Cutting over the authority below.

Correction: Odin is migrated first, not last

Found 2026-09-06 by deploying Heimdall. This document ordered Odin last, on the reasoning that Idunn reads Odin's topology to gate promotion and migrating Odin would move the thing gating the migrations. That is backwards.

A candidate's warming presence — the evidence Idunn requires before it will fence an incumbent — is observed through Odin's authenticated runtime topology correlation. advance_warming has exactly one exception:

if current.value.target == "odin" && snapshot.admitted_for("odin").is_none() {
    // first Odin bootstrap: presence observed directly

Only odin, and only while no Odin is admitted, may warm on directly observed presence. Every other target waits for Odin to publish. So with the previous generation's Odin still running — which publishes nothing the new Idunn reads — a Heimdall candidate starts, serves, publishes health, and warms indefinitely. It never fails and never promotes.

Verified live: the candidate ran on its assigned bind, and the transaction sat in Warming with no gate reason recorded until one was added.

Odin is the bootstrap target. It is not a dependency to defer; it is the root of the observation chain, which is also why it has the only recipe that was ever kept current. Migrate it first, admit it, confirm it publishes topology correlation, and only then expect any other target to reach promotion.

A related consequence for interpreted targets: health published over RUDP to the previous generation's --rudp-health-bind goes nowhere. The current serve has no such flag. A target still configured with GC_ACCESS_IDUNN_RUDP_HEALTH pointed at the old endpoint will log timeouts forever and is not the reason promotion stalls.

Per target

1. Fix the ref before you carry it forward

Seven of eleven targets are pinned to a codex/... branch, not main. The swarm goal is everyone on main and current with each other. A migration that copies admitted_ref = "refs/heads/codex/ghostlight-dungeon-mvp" into a binding has laundered a branch pin into a typed contract and made it harder to see.

Land the branch, or record in the binding's commit message why this target cannot be on main yet.

2. Write the recipe, in the target's repository

deployment/idunn/recipe.toml, schema gamecult.idunn.target_declaration.v1. It declares capability only — steps, artifacts, service argument shape, health contract, state slots, provides. It must name no host path, no image, and no privilege; TargetDeclaration::parse rejects unknown fields, and a recipe that reaches for host authority is rejected by admit() rather than honoured.

Several targets already have one. Recipes exist in Odin, Ghostlight, Ghostlight-interruptfu, CodexConnector, and the four Ghostlight-worlds variants — eight in total. So recipe authoring is not the bottleneck for those targets; the missing halves are the operator bindings and the daemon cutover.

Odin/deployment/idunn/recipe.toml is the reference. It is minimal, and idunn validate accepts it.

Do not copy CodexConnector's. It is the richest-looking example and it is stale: it declares required_gitlinks = ["vendor/cultcache-rs", "vendor/cultnet-rs"], but that repository has no .gitmodules, no vendor/, and now takes CultLib as a pinned cargo git dependency. The recipe describes a repository shape that stopped existing.

That drift is the general hazard, not a CodexConnector quirk: a recipe lives in the target's repo and nothing re-checks it when the repo changes underneath. idunn validate --recipe catches malformed recipes; it does not yet catch a recipe whose declared gitlinks are absent from the tree. Run it in each target's CI so drift fails at the repo, not on the host.

3. Write the binding, on the host

/etc/gamecult/idunn/bindings/<target>.toml, schema gamecult.idunn.operator_binding.v2. This is where privilege lives: origin and admitted ref, the runner image pinned by digest, workload roots and hardening, runtime trust anchor, route, brakes, rollout, placement, and the profiles this target joins.

Two brake stores, and they must differ:

[brakes]
deployment_store = "/var/lib/gamecult/idunn-authority/<target>-deployment-brake.cc"
lifecycle_store  = "/var/lib/gamecult/idunn-authority/<target>-lifecycle-brake.cc"

A binding naming one store for both is rejected — "deployment and lifecycle brakes are identical". That rejection is the doctrine the old generation could not express: a deployment brake must not be able to suspend daemon survival.

The binding must name every affordance the recipe's runners derive. Omitting one fails admit(). This is deliberate — a compromised target repository can change what gets built, but not what it may touch.

3b. Validate the recipe with the binding

idunn validate --recipe <recipe> --binding <binding>

Validating a recipe alone parses it and stops. Every rule that relates the two documents lives in OperatorBinding::admit, and admit does not run without a binding. Odin's recipe passed the recipe-only check for months while being structurally unadmittable: it declared [state], which forces the binding to carry a state root, which in turn requires the launch contract to carry a state_root argument -- and its arguments named an absolute store_path instead. A recipe-only "ok" is not evidence that a target can be deployed.

4. Dry-run, then admit

idunn up <target> --requested-by "$USER" --no-wait
idunn status --command <id>

Verify before promotion, not after: the candidate must hold a distinct UID, PID namespace and mount namespace from the incumbent (prove_isolation), and signed warming presence must be observed before the fence. If the target cannot publish signed health yet, that is the work — not a reason to widen the trust anchor.

5. Retire the legacy path for that target

Remove its line from the sudoers Cmnd_Alias, then its case arm, then its manifest under /srv/odin/deploy-manifests/. Sudoers first: the grant is the privileged half and must not outlive its consumer.

Validate with visudo -c -f before installing, and diff the resulting grant set against a backup afterwards. Removing the last entry from a Cmnd_Alias leaves a dangling \ continuation, and repairing that by hand is how you silently drop a * from a neighbouring grant and break a live target's deploy path — as happened here on 2026-09-06 to deploy streampixels, caught by diffing and not by reading.

The first three targets, and what each needs first

Surveyed 2026-09-06. None of the three can take a recipe as they stand. Each needs a change in its own repository first, and the changes are not the same shape, so they are not one piece of work. Ordered by how much has to happen.

streampixels — blocked on a product redirection, do not migrate

Superseded 2026-09-06. The findings below were surveyed before learning the product is changing direction. 2D animation could not express what the spec required; StreamPixels is moving to a 3D-rendered overlay, and whether that is achievable in WebGL or needs dedicated rendering infrastructure is still open. The client funding it reportedly cannot absorb rendering overhead, which is what makes the WebGL question load-bearing rather than a preference.

Its deployment shape is downstream of that decision. A WebGL overlay keeps roughly the current two-unit shape; rendering infrastructure is a new target class with hardware requirements Idunn has never expressed on this host. Writing a binding now would pin the shape being replaced.

Keep the survey below only as a record of the current deployment's defects, and do not act on it — in particular, do not repair the tsx-at-runtime path. It is being replaced, not fixed.

Both apps already have build scripts: apps/service runs tsc -p tsconfig.json, apps/web runs next build, and the root has pnpm -r build. No submodules, no file: dependencies. The obstacle is not the build.

  • The service does not use its own build. The unit runs node node_modules/tsx/dist/cli.mjs apps/service/src/index.ts — TypeScript transpiled at startup from a checkout at /srv/streampixels/app. Idunn seals artifacts; there is nothing sealed about a source tree plus a transpiler. Point the unit at the tsc output.
  • One legacy target is two Idunn targets. A recipe declares a single [service], and a binding a single unit_prefix. streampixels-service and streampixels-web have different environments, different ports, and an ordering dependency (web is After= service). They were one target only because the shell actuator restarted both with one docker compose line. Split them; the dependency belongs in the recipe's [[provides]]/dependency surface, not in a shared name.
  • Runtime artifact question to settle: a Node service's release is dist/ plus its production node_modules, unless it is bundled. Decide which before writing [[artifacts]].

repixelizer — needs an artifact story for Python

Simplest dependency story of the three: pyproject.toml, no CultLib dependency, no submodules. But it runs /srv/repixelizer/.venv/bin/python /srv/repixelizer/app/scripts/run_gui.py — an interpreter from a venv against a checkout, so there is no artifact to seal and no revision observable from the process. It needs a build step producing something exact (a wheel, or a venv materialized into the release root) before a recipe means anything.

Note also the name mismatch: the target is repixelizer, the unit is repixelizer-gui.

Ironically the most release-shaped of the three and the one needing the deepest change. It already deploys to /srv/heimdall/app/releases/<sha>/app behind a current symlink, which is exactly what release_root expects, and it builds with tsc to dist/.

But its package.json takes CultLib as "cultcache-ts": "file:../CultLib/packages/cultcache-ts" — a sibling checkout outside the repository. A sealed source cannot reach it, and no revision of Heimdall pins which CultLib was used. The current deploy manifest works around this by cloning CultLib separately and hardcoding cultlib_commit=5cefa0db... in shell, which is precisely the untyped authority the recipe model exists to replace.

The estate's answer is a vendor submodule: Ghostlight has vendor/eve, and required_gitlinks plus the binding's [repository.gitlinks] is how a recipe declares one. Heimdall needs vendor/CultLib as a gitlink and its file: dependencies repointed at it. Then the CultLib revision is pinned by the Heimdall commit, and the seal covers both.

Do this one last of the three, and expect it to be a real change to how Heimdall builds rather than a deployment edit.

What this survey says generally

Every one of these targets runs from a checkout or an unpinned sibling, and each was fine as long as a shell script did the deploying, because a shell script can just cd somewhere. The recipe model asks a question the old one never did — what exactly is this release, and can you name it? — and for three of eleven targets the honest answer today is no. That is the migration's real cost, and it is worth paying: it is the same question as "is everyone on main and current with each other", asked where it can be enforced.

Why retirement forces the migration

The previous generation cannot express that a target is retired. Its target list is compiled into the binary; idunn --help on the installed daemon offers restart and redeploy and no way to remove a daemon from supervision. So when codex-connector was stopped on 2026-09-05, the supervisor immediately began deciding:

Idunn decision for yggdrasil-codex-connector: restart
  (health is failed; restart authority is available)

— eighty log lines in ten minutes, against a service deliberately retired. The only brake that generation has is the deployment brake, and doctrine forbids using it here: a deployment brake must not suspend continuity. Retiring a target means suspending continuity for that target only, which is exactly what the current generation's lifecycle brake is, and exactly what the old one lacks.

Until cutover, the available mitigation is to remove the sudo grant, so the restart attempts fail at the privilege boundary rather than half-succeeding. That is a compensator, not an owner, and it is worth noticing that the estate found the argument for its own migration by trying to throw something away.

Gjallar, by contrast, was handled correctly, because its failure classified as dependency-unavailable rather than failed:

Idunn decision for yggdrasil-gjallar: alarm
  (local restart/deploy is not the owner of this failure)

Alarm, not resurrection. The distinction the old generation can draw is between failures it owns and failures it does not — not between a target that is broken and a target that is finished.

Host prerequisites for any routed target

Done on yggdrasil 2026-09-06. These are shared, not per-target: the first routed migration needs them, every later one reuses them.

nginx stream context. Debian ships ngx_stream_module as a dynamic module in a separate package, and it was not installed — --with-stream=dynamic in nginx -V with no .so present. Installed libnginx-mod-stream at 1.26.3-3+deb13u7, exactly matching the running nginx, so nothing else moved. Added a top-level stream block to /etc/nginx/nginx.conf including /etc/nginx/idunn-stream-routes/*.conf, and created that directory root:idunn 0775. nginx -t passed before the reload; after it, gamecult.org and heimdall.gamecult.org/healthz both still answered 200. Backup at /root/nginx.conf.bak-20260906-stream.

Note the shape this locks in: the vhost stays operator-owned and static. nginx keeps TLS, server_name and path routing and proxies to a stable local endpoint; Idunn owns only the hop from that stable endpoint to whichever candidate is admitted. Writing into /etc/nginx/idunn-stream-routes is the whole of Idunn's nginx authority, and stream configuration cannot do the things an http-context injection could.

Idunn runs as root, and the unit says why. This is the largest difference between the generations and it should not be discovered at install time.

The previous generation ran User=idunn and reached root through a narrow sudoers grant onto /usr/local/libexec/idunn-yggdrasil, a shell actuator. The current generation has no sudo anywhere in its source: it calls systemctl, systemd-run, nginx and docker directly, and a confined User= cannot actuate anything at all. docs/deployment-authority.md states the intended model — "Freeze the exact source and recipe as idunn, then copy and verify it into a root-owned actuation stage. The privileged driver never opens Git." — and --source-uid/--source-gid are validated as non-zero, which only makes sense for a privileged daemon dropping down for source work.

So the separation is internal rather than at the process boundary, and the protection is that Idunn accepts no imperative input: capability lives in the recipe, affordances in the binding, and cli_exposes_only_declarative_commands asserts there is no way to hand it a command string. The unit still runs under ProtectSystem=full with each actuated path re-opened individually, so the write set is enumerated even though the uid is root.

That is a real increase in blast radius over a confined process, and worth a deliberate look before the cutover rather than a shrug. The counter-argument is that the old shape was confined in name only: the process was sandboxed and the thing it invoked was an unaudited root shell script with eleven hardcoded targets.

Still outstanding here: the route driver stages preflight in /run/idunn/route-preflight; the unit now declares RuntimeDirectory=idunn, which creates and removes /run/idunn with the service.

Two .cc shapes, and a retracted claim about them

Corrected 2026-09-06. An earlier version of this section claimed the CultLib forks had diverged and that cultcache-ts could not read a cultcache-rs store. That was wrong, and it was wrong in the usual way: generalised from a single file.

The forks agree. cultcache-ts reads Idunn's live control store on yggdrasil without complaint — 36 records — because ordinary CultCache stores use the same framing in both runtimes: [formatVersion, catalog, records]. That covers the control store, the runtime bundle's expected.cc and activation.cc, and the process write lease.

The exception is narrow and deliberate. Service identity private stores are written by cultnet-rs's atomic_create_private_store, a minimal container holding one bare positional envelope:

[ [key, type, payload, stored_at, schema_id] ]

That is a private-key container, not a record store, and cultcache-ts rejects it — invalid_type: expected object, received array. Heimdall reads that one shape in src/idunn-store.ts; everything else goes through the ordinary client.

The cost of getting this wrong is worth naming, because it was nearly shipped. A consumer that hand-decodes the private-store framing and applies it to expected.cc and the write lease will fail on first deployment, and its unit tests will pass, because hand-built fixtures agree with the hand-built reader. Build fixtures with the CultCache client so a test can disagree with you.

Per-target host preprovisioning

Idunn does not create a target's roots; it refuses to deploy into paths that are not already shaped correctly. Each check exists so a compromised or careless binding cannot widen access, and each one cost a failed deployment to discover:

Path Required shape Check
state_root root:<state_group>, mode 2770 must be root-owned, group-owned by the state group, not world-writable, and setgid so the workload's dynamic user inherits group access
cache_root owned by the runner's container uid, mode 0700 "dedicated exact-identity 0700 directory" -- the uid is the runner's user, not the source identity
cache_root parent root-owned, not group- or world-writable /srv/build is idunn:idunn and therefore fails; put caches under Idunn's own root
frozen source stage root-owned, non-writable source is frozen as idunn, then copied into a root-owned actuation stage
runner network must exist the binding names a docker network; the operator provisions it
runtime presence identity root:root, mode 0400, nlink 1 passed to the workload as a parent-only descriptor, so it must be unwritable and unaliased -- a second hard link would be a second path to the signing key

Secrets reach the workload as systemd credentials, not as readable files. The workload runs under DynamicUser, so it cannot open a heimdall:heimdall 0600 key no matter where it sits, and giving it a supplementary group to make that work would be widening access to fix a permissions error. Put the secret in [workload.secret_files] instead: Idunn loads it as a credential and sets an environment variable named after the entry, whose value is the credential path. Naming the entry after the variable the service already reads -- GC_ACCESS_SIGNING_PRIVATE_KEY_PATH for Heimdall -- wires it up with no code change at all. Setting the same name in [workload.environment] as well is refused as a collision, which is the mechanism telling you there is one owner.

The Idunn unit also needs the target's roots. ProtectSystem=full makes /etc read-only, so a target whose runtime_root is not in ReadWritePaths fails at "creating runtime bundle". Every migration adds exactly three paths -- runtime root, state root, release root -- and that list is the honest blast radius of running Idunn as root.

What the Odin migration cost, and what it fixed

Odin is the bootstrap target, so five things that had never been exercised all failed on the way through. Each one is now a test.

A routed RUDP target could be admitted but not projected. admit accepts (route_required, Rudp, nginx-stream-udp) against an rudp:// endpoint, and the nginx driver already wrote listen ... udp reuseport -- but endpoint_scheme lumped RUDP in with Private and refused to name a scheme, so expected_projection bailed. Odin is the only routed RUDP target, and nothing else can warm until Odin is admitted.

Only a step's declared required_environment reaches its container. A runner's [runners.<id>.environment] is not ambient: names not listed on the step are dropped. Odin's steps declared none, so CARGO_HOME never arrived and cargo fell back to the image's read-only /usr/local/cargo.

A build container has no machine identity. CultLib's Linux protector binds a service identity seed to /etc/machine-id; the build image carries none and the runner is --read-only, so any target whose tests enrol an identity failed every step. Idunn now derives a machine-id per frozen workspace and mounts it read-only. Do not "fix" this by mounting the host.s: that would let a build container protect a seed that unwraps on the host, which is the property the binding exists to deny.

The published projection was inside Idunn's private root. Every managed target must read the topology store to verify its own Expected incarnation against the Idunn anchor, and it sat in a 0750 idunn:idunn directory no workload could traverse. It now lives in /var/lib/gamecult/idunn-projection, world-readable, integrity protected by signature rather than by mode.

A target's signing identity does not belong in its state root. state_root is writable by the workload, and a daemon that can rewrite its own signing identity does not have one. Odin's topology identity moved to the runtime root.

The Odin bootstrap added five more, every one of which cost a candidate that started, ran, and then died on a file it could not open:

Path Required shape Why
runtime_root and every directory above it traversable by the workload: o+x, or group-owned by the state group with g+x the workload is a DynamicUser and owns nothing, and ReadOnlyPaths= binds the bundle's leaf into the namespace without granting traversal above it. Idunn now checks the whole chain and names the closed directory
runtime_root setgid, group-owned by the state group (2750 root:<state_group>) harden_root_authority_file requires the write-lease record's group to equal its parent's, and only setgid makes a newly created record inherit it. Without it the record lands root:root and the workload cannot read its own lease
the write-lease record root:<state_group>, mode 0640 follows from the setgid parent; the workload reads it through the state group. Idunn writes it, so fixing an existing wrong-group record means deleting it, and that is safe only when no transaction is live
/var/lib/gamecult/idunn-projection default ACL u::rw-,g::r--,o::r-- Idunn runs with UMask=027, so a store is created 0640 and each publish re-opens it 0644; the default ACL sets the mode at creation and closes that window for stores. The .lock is not published and no reader opens it: Idunn creates it 0600 (replacing one found wider, so a descriptor another uid already holds is orphaned), and the ACL never decides its mode
/etc/nginx/idunn-stream-routes root:root, not group-writable "route authority parent is not canonical root-owned and nonwritable". It was root:idunn 0775 from the generation where Idunn ran unprivileged and needed to write it as a group member

Two shapes are worth stating plainly because they are easy to get backwards. A store's .lock sibling is opened whenever the store is, so a 0640 lock denies a read exactly as a 0640 store does. And CultLib's backing store reports an unreadable file as an empty store rather than an error, so every one of these permission faults arrives wearing a different costume: "runtime authority store must contain exactly one record", or a candidate that decides it holds no write lease and warms forever. When a store looks empty or a record looks missing, check whether the reader can open it before believing the content.

Abandoning a transaction past Fencing

begin_pre_fencing_abort is gated on phase < DeploymentPhase::Fencing. After the fence, every error went to record_resumable_error and the transaction retried forever; there is still no operator verb to cancel one, and no server-side expiry -- --timeout-seconds bounds the idunn up client's wait, not the transaction.

That is correct while a candidate can still recover. It is a trap when the candidate never can: a transient unit with Restart=no that has failed will not come back on its own, so the transaction holds the target and every later command for it stays queued indefinitely.

A candidate that is permanently stopped -- its transient unit failed, or gone from systemd entirely -- now aborts instead, withdrawing its route, write lease, process and projection in that order, and restoring the incumbent's admitted Expected so continuity can bring it back.

Found the hard way during Odin's first deployment, and made unrecoverable by deleting the target's write-lease record to fix its mode while a transaction held it -- observe_exact then reports "physical write lease disappeared after Granted became durable", which is exactly the tamper it is there to catch. Do not remove a lease record, projection record or brake store belonging to a transaction that is not terminal; change the mode in place, or fix the shape that produced the mode and redeploy.

Cutting over the authority

Idunn last, and not by deploying Idunn with Idunn.

  1. Build the current Idunn on Linux and stage it beside the running one — do not overwrite /usr/local/bin/idunn while the old daemon is supervising.
  2. Create /etc/gamecult/idunn/bindings/ and the per-target brake stores.
  3. Install deploy/idunn-yggdrasil.service from this repository. It invokes idunn serve and names every store explicitly.
  4. Stop the old unit, move the binary into place, daemon-reload, start.
  5. Verify continuity actually actuates — kill a managed daemon and watch it come back — before trusting the cutover. A control plane that starts is not a control plane that supervises.

The window matters. Between step 4's stop and a verified step 5, nothing is supervising the swarm. Do it with the targets already migrated, so the new daemon has bindings to load and the window is short.

Retiring Codex

Decided by the operator 2026-09-05: the estate is not going back to Codex. Generic token capacity comes from elsewhere, and anything served to third parties needs an EU supplier with a DPA — together.ai is the current direction. That makes the Codex integration a maintenance liability with no consumer, and it is deep enough to be worth naming before anyone starts pulling.

Live state. codex-connector.service was active (running) and failing 401 token_expired on a three-minute loop against https://chatgpt.com/backend-api/codex/models, with nothing connected to port 4103. Stopped and disabled 2026-09-05; the port is closed and the loop has ended. It had consumed 1min 30s of CPU and peaked at 1.2 GB doing nothing but retrying expired credentials.

Two loose ends that stop left behind:

  • ghostlight-dungeon.service carries Environment=GHOSTLIGHT_MODEL_CONNECTOR=127.0.0.1:4103, which now points at nothing. It had logged nothing for 24 hours before the stop, so this broke no working path — but it is where the provider replacement lands first.
  • epiphany-model-connector.service binds the same port with --model gpt-5.4 --codex-home .... It is inactive and disabled. Two Codex connectors were competing for one endpoint, which is duplicate authority of exactly the kind the census was looking for; both are now off, and only one of them has a repository.

Blast radius, in the order it should come out:

Surface What it is
codex-connector.service on yggdrasil running, 401-looping, no consumers
the sudoers deploy/restart codex-connector grants privileged half — remove before the script
GameCult/CodexConnector the whole repo; a transport for a provider we no longer buy
Epiphany/epiphany-openai-codex-spine an OpenAI/Codex adapter crate
Epiphany/epiphany-codex-bridge + vendored app-server Codex JSON-RPC protocol edge
VoidBot config turnCodexModel, mindCodexModel, imaginationCodexModel, codexModelReasoningEffort and their model lists
~/.codex/AGENTS.md and per-repo AGENTS.md doctrine maintained for a second agent runtime

Do not simply delete the Epiphany and Ghostlight side. Those are minds that need an inference transport; CodexConnector was one implementation of that seam, and the seam is worth keeping. The correct shape is to replace the provider behind it, not to remove the boundary and let each mind grow its own HTTP client — that would be re-forking the wire law CodexConnector's README exists to prevent. Retire the Codex-specific backend; decide deliberately whether the transport daemon is rebuilt against the new supplier or whether CultNet already covers it.

Sequencing note: epiphany and epiphany-capstone-17 are on this migration list. Do not write bindings for them until the provider question is settled — their deployment shape depends on whether they still front a transport daemon.

What is not carried forward

Odin@ed48185 ("Supervise Bifrost Persona feedback deployment", 2026-07-18) added a hardcoded bifrost-persona-feedback target with a stale-deployment failure contract and restart_on_missing_publication. It never reached this repository — it landed on Odin main after the extraction branch diverged, and 330e4cd deleted the machinery it was written against.

It is preserved at the pre-idunn-extraction-main tag in Odin. When bifrost-persona-feedback is migrated, that commit is the specification for what its health contract must express — re-expressed as a recipe [service.health] contract, not restored as Rust.