archy/docs/bitcoin-multi-version-design.md

Bitcoin Multi-Version Support — Design

Status: design (2026-06-22) Goal: let a user choose which version of Bitcoin Core / Bitcoin Knots to install (latest pre-selected, older versions in a dropdown), and later switch versions or opt into auto-update — all manifest/catalog-driven, all served from our signed registry, rootless, with zero data loss across version changes.

See also: docs/registry-manifest-design.md (catalog distribution + signing this builds on), docs/PRODUCTION-MASTER-PLAN.md (gate that must be green first), MEMORY → project_decoupled_app_updates, MEMORY → project_manifest_driven_north_star.

Scheduling: this is net-new scope. It lands after the production test gate (tests/lifecycle/run-20x.sh) is green on .228 + .198. The data- preservation invariant (downgrade vs. chainstate) is the highest risk here.

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1. Where we are today

Image source / build

Thing	Today
apps/bitcoin-core/Dockerfile	FROM bitcoin/bitcoin:24.0 — a community image, stale (manifest says 28.4), no project-official Docker image exists
apps/bitcoin-knots/	no Dockerfile — :latest is built/pushed by hand
Registry	scripts/image-versions.sh → ARCHY_REGISTRY="146.59.87.168:3000/lfg2025"; only BITCOIN_KNOTS_IMAGE=…/bitcoin-knots:latest pinned, no Core pin
Tags in registry	one tag per image. No historical versions.

Version pinning

• apps/bitcoin-core/manifest.yml → …/bitcoin:28.4 (pinned).
• apps/bitcoin-knots/manifest.yml → …/bitcoin-knots:latest (floating — a liability for reproducibility and for "switch back to the version I had").
• core/archipelago/src/container/app_catalog.rs + app-catalog/catalog.json: signed, hourly-fetched, carries version (badge text) + image. catalog_image_override() overrides the manifest image only if same-repo. available_update_for_app() already ignores floating tags for update detection.

Install path

• prod_orchestrator.rs::install_fresh() resolves the image as manifest image → catalog override → pull. There is no per-install version parameter — orchestrator.install(app_id) takes only the id.
• RPC package.install (api/rpc/package/install.rs) accepts dockerImage / version params but for orchestrator-managed apps (bitcoin-core / bitcoin-knots are allowlisted) it ignores them and lets the orchestrator resolve.
• Conflict guard (prod_orchestrator.rs ~1306–1325): core and knots may not run simultaneously. Must be preserved by everything below.

UI

• Install is one-click, no modal (MarketplaceAppDetails.vue::installApp()).
• Update badge + "Update to X" already exist (appDetails/AppHeroSection.vue, RPC package.update).
• No Bitcoin-specific settings panel; all apps share AppSidebar.vue.
• Per-app config persisted only at install time as containerConfig → /var/lib/archipelago/app-configs/<id>.json. No post-install set-config RPC.

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2. Source-of-truth decision: official upstream → our registry

We use the official releases as upstream provenance, but nodes only ever pull from our registry. Nodes do not fetch bitcoin.org / GitHub at install time — that would break rootless/offline installs and the signed-registry trust model, and neither project publishes an official Docker image anyway.

Official sources (verified):

Impl	Index	Per-version asset pattern
Bitcoin Core	bitcoincore.org/en/releases · github bitcoin/bitcoin	https://bitcoincore.org/bin/bitcoin-core-<ver>/bitcoin-<ver>-x86_64-linux-gnu.tar.gz + SHA256SUMS + SHA256SUMS.asc
Bitcoin Knots	github bitcoinknots/bitcoin · bitcoinknots.org/files	https://bitcoinknots.org/files/<maj>.x/<ver>/bitcoin-<ver>-x86_64-linux-gnu.tar.gz (<ver> e.g. 29.3.knots20260508)

Both ship signed binary tarballs with multi-builder Guix attestations (SHA256SUMS.asc). The build pipeline verifies these once, at build; our DHT Phase 0 registry signature then carries provenance to the fleet.

Knots version strings embed a build date (29.3.knots20260508). Treat the full string as the tag; surface a friendly 29.3 + date in the UI.

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3. Design

Phase 0 — Reproducible, verified image pipeline (prerequisite)

New scripts/build-bitcoin-image.sh <impl> <version> that, per version:

1. Downloads the official tarball + SHA256SUMS(.asc) (GitHub release assets are an identical mirror → fallback).
2. Verifies SHA256 and the Guix/builder GPG signatures. Fail closed.
3. Builds a minimal rootless image: pin a small base, unpack bitcoind/bitcoin-cli. Keep the existing entrypoint probe (command -v bitcoind || find /opt -path '*/bin/bitcoind') so per-version layout differences don't break startup.
4. Tags + pushes :<version> and updates the default pin (:latest / :28.4-style) to the registry.

Curate, don't mirror everything. Publish a bounded set (proposal: current + last ~3 majors), e.g. Core 31.0, 30.0, 29.3, 28.4, 27.2 and Knots 29.3.knots…, 28.1.knots…, 27.1.knots…. log / document dropped versions — silent truncation reads as "all versions supported" when it isn't.

Also fixes existing debt: replaces the stale community FROM bitcoin/bitcoin:24.0 and gives Knots a real Dockerfile + non-floating tags.

Phase 1 — Version catalog (signed, registry-distributed)

Extend AppCatalogEntry (forward-compatible — no deny_unknown_fields, old nodes ignore it):

"bitcoin-core": {
  "version": "31.0",                 // default / latest (existing field)
  "image": "…/bitcoin:31.0",         // existing
  "versions": [                      // NEW
    { "version": "31.0", "image": "…/bitcoin:31.0", "default": true },
    { "version": "30.0", "image": "…/bitcoin:30.0" },
    { "version": "28.4", "image": "…/bitcoin:28.4", "deprecated": true, "eol": "2026-...." }
  ]
}

Published to releases/app-catalog.json, signed by the existing release-root mechanism. This is the single source of truth the UI reads for "what can I install / switch to," and third-party-registry apps inherit the capability for free. version/image stay as the default for back-compat.

Phase 2 — Install-time version selection

• Orchestrator: add install_with_image(app_id, Option<image_tag>) (or an optional arg on install). When a tag is supplied, validate same-repo against the manifest (reuse image_without_registry_or_tag()), then override in install_fresh(). Default path unchanged. Preserve the core/knots conflict guard.
• RPC: thread the selected version/image from package.install into the orchestrator for the allowlisted apps (the param is already received — just not forwarded).
• UI: the first install modal in the app — latest pre-selected, dropdown of versions[], deprecated/EOL badges on old entries. On confirm, pass the chosen version to package.install.

Phase 3 — In-app version switch + auto-update toggle

• UI: a Bitcoin "Version & Updates" card (conditional in AppSidebar.vue for bitcoin-core / bitcoin-knots): current version, a switch dropdown, and an auto-update-to-latest toggle.
• Switch = controlled re-pull/recreate reusing the package.update machinery but targeting an arbitrary (incl. older) tag → effectively package.set-version.
• Persistence: new package.set-config RPC writing the existing app-configs/<id>.json ({ pinnedVersion, autoUpdate }).
• Auto-update: the existing hourly catalog check, when autoUpdate:true, triggers package.update to the catalog default. A pinned version suppresses the update badge.

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4. Invariants & safety rails

• Rootless only. Pipeline images and run path stay rootless; no Docker-socket, no privileged.
• No data loss across version change. Preserve /var/lib/archipelago/bitcoin, secrets (bitcoin-rpc-password, …-rpcauth), ports, and the adoption container name on every install / switch / update.
• ⚠️ Downgrade vs. chainstate (highest risk). Bitcoin Core refuses to start on a chainstate written by a newer version unless reindexed (expensive, or data loss on a pruned node). The UI must warn loudly on downgrade; the orchestrator should gate/confirm it and never silently wipe. Pruned nodes can't simply -reindex.
• Core ⇄ Knots switch stays governed by the existing conflict guard; treat an impl switch as distinct from a version switch.
• Floating tags (latest) are never advertised as a selectable "version" and never counted as an available update (already handled by available_update_for_app).
• Verify on a real node (.228 then .198) and pass run-20x before any tag.

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5. Files / seams (no code yet)

Concern	File
Image build/push	new scripts/build-bitcoin-image.sh; apps/bitcoin-core/Dockerfile; new apps/bitcoin-knots/Dockerfile; scripts/image-versions.sh
Catalog schema	core/archipelago/src/container/app_catalog.rs; releases/app-catalog.json (+ app-catalog/catalog.json)
Install override	core/archipelago/src/container/prod_orchestrator.rs (install / install_fresh); api/rpc/package/install.rs; api/rpc/dispatcher.rs
Switch / set-config RPC	api/rpc/package/update.rs; new package.set-config handler; app-configs/<id>.json
Install modal	neode-ui/src/views/MarketplaceAppDetails.vue; new …/marketplace/AppInstallModal.vue
Version & Updates card	neode-ui/src/views/appDetails/AppSidebar.vue; neode-ui/src/api/rpc-client.ts; neode-ui/src/types/api.ts

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6. Open questions

1. Curated version set — how many majors back do we host, and storage budget on the registry?
2. Multi-arch — fleet is x86_64 today; do any nodes need arm64 images?
3. Pruned-node downgrade policy — block outright, or allow with an explicit "this will require re-sync / may lose pruned data" confirmation?
4. Auto-update default — off (opt-in) for a consensus-critical app like Bitcoin? (Recommended: off, explicit opt-in.)
5. Knots date-suffix UX — how to display 29.3.knots20260508 cleanly.

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Sources

• Bitcoin Core releases
• bitcoin/bitcoin releases
• bitcoinknots/bitcoin releases
• Bitcoin Knots
• bitcoin.org version history