# arr — design One service that replaces Radarr and Sonarr, and later Bazarr, for a single household. Rust workspace, API-first, SQLite, no authentication layer. This document is the contract. Issues reference it by section rather than restating it. --- ## 1. Why Five .NET services idle at 600-900 MB to do a job with one loop in it: decide what you want, find it, fetch it, put it somewhere Jellyfin can read. Each has a configuration surface an order of magnitude larger than the subset actually used, and none of them share a model, so the same show is configured three times in three dialects. The replacement targets 20-40 MB resident, one binary, one database, one policy language. This is not a general-purpose Radarr replacement. Every decision below is allowed to be narrow. ## 2. Non-goals Explicitly out of scope, permanently unless stated: - **Authentication.** The perimeter is a VPN plus Authelia at the proxy. The service binds without auth, same trust model as the existing Transmission RPC. - **Library migration or filesystem scan.** The service knows only what it put on disk. Adopting the pre-existing library, if ever wanted, is a one-off script against both APIs, not a feature. - **Automatic quality upgrades.** See §5.4. - **Multiple quality profiles.** Policy attaches to a root folder. See §5.1. - **Trakt.** Jellyfin and Stremio already write watch state there and nothing in this pipeline reads it. - **Calendar view, actor/director following, per-indexer UIs.** Prowlarr owns indexer configuration and keeps doing so. - **Books and music.** `shelfmark` and `calibre-web-automated` already cover books. If they ever land here they reuse maybe three of the ten crates, so nothing is generalised in advance. See §11. ## 3. System context ``` ┌──────────────┐ TMDB ──────▶│ │ │ arr │────▶ Transmission RPC 10.6.10.45:9091 Prowlarr ──────▶│ │ (Torznab) │ (this) │────▶ ffprobe local subprocess │ │ Jellyseerr ─────▶│ │────▶ Jellyfin refresh 10.6.10.18:8096 (Radarr-compat) └──────┬───────┘ │ ntfy per-person topics ▼ SQLite + media tree on /mnt/media ``` Everything already exists except `arr`. Prowlarr keeps owning tracker auth, Cloudflare bypass via FlareSolverr, rate limiting and the Cardigann definitions — replacing it buys nothing. Transmission runs natively in its own LXC (VMID 130, `10.6.10.45`), RPC unauthenticated, download dir `/mnt/media/transmission/complete`. ## 4. Domain model Movies and series are separate aggregates. They share machinery, not a table. ``` Root id, kind (movie|tv), audience (main|kids), path, policy_id Policy id, name required_audio rule set, see §5.2 dub_blacklist [pt-BR] hdr_rules see §5.3 size_bands per resolution: floor, target, penalty curve, all per episode (§5.5) resolution_pref [2160p, 1080p] source_weights small tiebreaker Movie id, tmdb_id, title, year, original_language, root_id wanted (bool), overrides (json), state, blocked (bool) search_attempts, last_searched_at Series id, tmdb_id, title, year, original_language, root_id auto_track (bool), overrides (json), blocked (bool) Season id, series_id, number, tracked (bool) Episode id, season_id, number, title, air_date wanted (bool), state search_attempts, last_searched_at MediaFile id, owner_kind (movie|episode), owner_id, path, size probed (json: resolution, source, hdr, audio_tracks, sub_tracks) waiver (json|null) which rule was relaxed to allow this import Release id, indexer_id, guid, name, size, seeders, publish_date, download_url parsed (json) what the name claims score, verdict eligible | waived | rejected(rule) Grab id, release_id, target_kind, target_id, infohash state, grabbed_at, imported_at Blacklist infohash, normalised_name, reason, created_at Owner id, name, ntfy_topic TitleOwner title_kind, title_id, owner_id many-to-many ``` ### 4.1 Intent lives at the leaf Sonarr's `monitored` conflates "do I want this show" with "is anything happening right now". It is user-maintained, so it drifts and stops meaning anything. Here, intent is `Episode.wanted` and `Movie.wanted` only. `Series.auto_track` is not intent — it is a rule one level up: when metadata reveals a new season, that season becomes tracked. The rule applies from the second refresh onward: seasons revealed by a series' first refresh — the whole back catalogue present at add time — are never tracked by it. Only seasons that appear after the series was added are covered; back-catalogue seasons are picked by hand. An untracked series where you manually marked S02 needs no special case: three wanted episodes, nothing else. `Season.tracked` is also a rule, not intent. Turning tracking on marks every already-revealed episode in the season wanted, and keeps marking episodes wanted as metadata reveals them. Turning it off clears `wanted` on every episode of that season: toggling the flag is itself the explicit act, and the product offers no other way to withdraw a season's worth of intent. Without that, untracking leaves a series with every season off and every episode still wanted, pinned at `incomplete` with no way back. Marking individual episodes wanted on a season that was never tracked is unaffected by any of this. Both rules skip season 0. Specials are dozens of undated shorts and recaps that indexers do not carry, so `auto_track` never marks season 0 tracked. See §4.2 for how season 0 stays out of derived status. ### 4.2 Status is derived, never stored as intent Recomputed on metadata refresh and on file change: | Status | Condition | |---|---| | `airing` | an episode aired or airs within ±14 days | | `incomplete` | wanted episodes missing, nothing currently airing | | `waiting` | season finished, next unannounced or future-dated | | `complete` | everything wanted is on disk | | `ended` | series finished upstream and complete | Default list view shows `airing` and `incomplete`. Everything else collapses behind one toggle. A one-off season grab therefore disappears from the default view by itself once satisfied, and a tracked show reappears by itself when a new season is announced. Nothing to remember to flip. Status chips carry state colour, not a single informational hue: green (`--signal-ok`) for on disk or complete, amber (`--signal-warn`) for wanted but not yet found, violet (`--status-airing`) for downloading, neutral for untracked. The word stays present in every chip, so state survives with colour removed. Season 0 is invisible to all of it: derived status ignores season 0 episodes entirely, so a manually wanted special cannot pin a series at `incomplete` or hold back `ended`. The accepted consequence is that specials are visible and grabbable in the series detail view, but never affect status. ### 4.3 People are tags, not paths `Owner` is a many-to-many tag on titles. It drives UI filtering, the default list, and notification routing. It never appears in a path. A file lives in one place; audiences overlap. ## 5. Policy engine The core of the app and the part worth testing hardest. Lives in `arr-core`, pure, no IO. ### 5.1 Policy attaches to a root Two roots per media kind (`main`, `kids`), each with one policy. Jellyseerr's "pick a quality profile per request" model is satisfied by exposing exactly one fake profile per root and ignoring whatever it sends. Per-title `overrides` relax the root policy for one title. Same mechanism in both directions — `only_4k` tightens, `allow_english_audio` loosens. **Stored verdicts follow the effective policy.** A release's verdict is stamped by the search that found it, and both §9.3's deck and the daemon's manual-grab gate read that stored column. So the four operator actions that change a title's effective policy — editing its overrides, moving it to a root with a different policy, pointing a root at a different policy, and editing the contents of a policy some root points at — re-derive the stored verdicts of everything they touch, inline in the same request. The operator is never left reading a verdict computed under a policy that no longer applies. The fourth is the widest: a repoint moves one library, a policy edit moves every library sharing the policy. Inline still holds there. Re-evaluation is pure and in-memory, a row whose verdict does not move is not rewritten, and the ceiling is the whole database rather than something that grows with the number of roots — roots partition titles, and a title has exactly one root. Measured over 2000 titles and 10 000 stored releases split across two roots sharing one policy: 0.36 s when the edit moves no verdict, 2.7 s in the pathological case where it moves all 10 000. A rename changes no rule and re-derives nothing. ### 5.2 Language Requires a concept the release name does not carry: the **original language of the title**, from TMDB, distinct from a track's language. ``` reject audio track T if T.lang ∈ dub_blacklist and T.lang ≠ title.original_language ``` `dub_blacklist = [pt-BR]` globally. That single expression covers both roots: - **main** — require a track matching `original_language`. Others may ride along. A Brazilian film has `original_language = pt-BR`, so its own soundtrack passes; a pt-BR dub of an English film does not. - **kids** — require pt-PT, or `original_language` when that is already Portuguese. pt-BR never satisfies the requirement, because the child does not read and a Brazilian dub is not what he should be watching. - **subtitles** — no blacklist. pt-BR subtitles are always fine. **The pt-PT / pt-BR detection problem.** ISO-639-2 has one code, `por`, for both. `ffprobe` reports `por` either way. Three signals in order: 1. Release name markers — Brazilian releases self-identify loudly: `PT-BR`, `Dublado`, `Nacional`, `Dual Áudio`. 2. `ffprobe` stream *title* and `handler_name` strings, not the language code — often literally `Portuguese (Brazil)`. 3. Container-level BCP-47 tags where present (Matroska can carry `pt-BR`). When none resolve it, tag the track `por-unverified` and surface it. Do not guess. Guessing toward `kids` gives a child a Brazilian dub; guessing toward `main` rejects a Brazilian film's own audio. **Sourcing consequence for `kids`.** European Portuguese dubs live almost entirely in streaming WEB-DLs (Disney+, Netflix, Max) and essentially never in BluRay encodes or remuxes. That root biases hard toward WEB-DL sources, and unlike audio in general it *is* often pre-grab visible, since multi-audio releases advertise themselves (`MULTi`, `DUAL`, explicit language lists). When nothing qualifies, the title sits in a visible **no-PT-source queue** rather than being grabbed in English. That queue is acted on manually, sometimes for months. A per-title `allow_english_audio` override empties one item from it with one click, and the resulting file is recorded with a `waiver` so the UI shows it as "English, no dub" rather than a clean match. ### 5.3 HDR and Dolby Vision The naive rule "blacklist Dolby Vision" is wrong and would discard a large share of good 4K releases. | Profile | Base layer | Behaviour without DV support | Verdict | |---|---|---|---| | 5 | none (ICtCp) | green/purple, unwatchable | **reject** | | 7 | dual-layer BL+EL | depends on player, unreliable | **reject** | | 8.1 | HDR10 | plays as HDR10 | **accept** | The existing library is already almost entirely Profile 8.1 with no Profile 5, and Jellyfin tonemaps it correctly on the current GPU path. Profile is knowable only from `ffprobe`, never from a release name. A `DV` chip in search results means "the name claims DV" and its absence means nothing. ### 5.4 Quality, and why there is no upgrade loop Default: take 4K if it exists now, otherwise 1080p. Per-title `only_4k` rejects 1080p outright and keeps searching indefinitely — the escape hatch for the handful of titles worth waiting on. **No grab delay.** Deliberately rejected. Radarr's delay profile exists to stop first-match-wins from always yielding 1080p; here the `only_4k` flag solves the same problem upfront and without making every grab slower. **No automatic upgrade loop.** An automatic upgrade re-downloads 40-80 GB and restarts a seeding obligation for something already watched. `needs_upgrade` is a marker in the UI and a manual "search again" button, not a background job. ### 5.5 Scoring: distance from a target size Source tier is **not** the dominant term. A remux should win only when nothing smaller exists. Per resolution, a floor, a target and a growing penalty above target. For 4K: floor ~8 GB, target ~22 GB. A 20 GB WEB-DL sits at target and wins; a 60 GB remux scores badly but stays eligible, so it is picked when it is the only option. The floor matters — unbounded "smaller is better" selects a 3 GB 4K encode that looks like mud. **A band describes one episode.** For a movie the question never arises — one release is one film. For TV a release may carry a single episode, several, or a whole season, and the shipped TV numbers are episode numbers: a 1080p target of 2 GiB is what one episode should weigh, not a ten-episode pack. So a release is measured by its size divided by the number of episodes it covers, and that per-episode figure is what both the target penalty and the floor are compared against. A 20 GiB pack of ten episodes is scored as 2 GiB and sits at target, not ten times above it. The floor takes the same figure. It is a hard reject rather than a penalty, so comparing a pack's total against an episode-sized floor lets every pack through untested — wrong in the opposite direction from the target penalty. The floor exists to keep a 3 GB 4K encode out, and a pack of ten such encodes has to fail it just as plainly. **An unknown episode count is one episode.** A release matched before its season's episodes have been revealed by a metadata refresh has nothing to divide by, and the rule does not guess a number: the divisor is 1 and the release is measured by its full size. That is the behaviour today, and it makes a pack look oversized rather than undersized — it fails toward rejecting a good pack rather than grabbing a bad one, and the next search after a refresh has the real count. **A band describes a rate, not a fixed size per episode.** The shipped values are read against a **reference runtime of 45 minutes**: a 1080p target of 2 GiB means 2 GiB per 45 minutes of episode. Before the per-episode figure is compared against them, a band's floor and target are both scaled by `runtime / 45`, where `runtime` is the series' minutes-per-episode from TMDB metadata. For a typical drama around 45 minutes the shipped numbers keep exactly their current meaning; a 22-minute show is judged against roughly half the floor and half the target instead of being rejected for weighing half of what an hour of video weighs. The shipped band values themselves do not change — the reference runtime is chosen so they do not have to. **A missing or zero runtime is the reference runtime.** When metadata carries no per-episode runtime, or carries zero, the scale factor is 1 and the band applies unscaled — exactly today's behaviour. The rule does not guess a duration, for the same reason the unknown episode count does not guess a number. **Movies are not scaled.** This applies to episodes only. A movie's bands are already tuned against feature length, so its floor and target keep their current meaning regardless of the movie's own runtime. Source tier (`Remux > BluRay > WEB-DL > WEBRip > HDTV`) survives as a small tiebreaker. Seeders are log-scaled and small: enough to complete, past that it does not matter. Telesync, CAM and screener are **hard filters**, not low scores. **How resolutions rank against each other.** Size is scored against the band for the release's own resolution, so on its own it says nothing across resolutions: an at-target 4K and an at-target 1080p both score the top of the size term, and a 4K a couple of gigabytes over target loses to a 1080p that is merely on target. That is wrong — `resolution_pref` is an ordered list, and the order is a preference, not just an eligibility filter. So each step up `resolution_pref` is worth a fixed number of points. The last entry is worth nothing and every earlier one a step more. A resolution the list does not carry scores nothing rather than being penalised, the same as an unclaimed resolution: no ranking is no opinion. The step is sized against the size term, not chosen in isolation. With the seeded 4K band — target 22 GB, 60 points per gigabyte over — a step of 300 is five gigabytes of overshoot: a 4K up to about 27 GB beats an at-target 1080p, and a bloated 40 GB 4K does not. Below target the same arithmetic asks a 4K to be within about four gigabytes of its target to win, which is what keeps an 8 GB 4K that looks like mud from beating a good 1080p. Exact numbers are policy rows, tuned by hand. The model is the decision. ### 5.6 Two phases of truth Release names lie or omit. Files do not. - **Pre-grab** — parse the name. It is all there is. Use it for hard filters (source type, resolution, explicit language markers) and for scoring. - **Post-download** — `ffprobe` before import. Real audio languages, real HDR format and DV profile, real codec, real duration. Store both, `parsed` on the release and `probed` on the file. The gap between them is also data: it tells you which release groups mislabel. ### 5.7 Hard fail versus soft fail A policy violation found by `ffprobe` is not one thing. - **Hard fail** — useless. No original-language audio track at all, DV Profile 5, wrong title, corrupt. Do not import, blacklist the release, grab the next candidate. - **Soft fail** — watchable but not what was asked. 1080p while `only_4k` was set, PT audio missing on a `kids` title. Import it, record a `waiver`, surface it. Neither deletes the torrent. See §7.3. **Two hard failures make a decision, and only for 30 days.** A movie, an episode or a season enters the needs-a-decision queue (§9.5) when two grabs against *different* releases hard-failed on it, and both of those failures happened within the last 30 days. One bad torrent is not a decision — a release that hard-failed is blacklisted (§6.3) and the next candidate is grabbed, which is the system working. The window runs from the failure, not the grab. The two are usually minutes apart, but a torrent can sit stalling on a dead swarm for five weeks before `ffprobe` finally condemns it — and that failure is fresh evidence the target is broken now, not history. Measured from the grab it would be born outside the window and a genuinely broken target could never surface. So `grabs` records `failed_at` alongside `grabbed_at`, and the window reads it. The window is what lets the queue be emptied. Nothing clears a `grabs` row, so without it the queue only ever grows and the one season that wants attention sits behind eight that were dealt with months ago. It is the queue's version of §6.2's "it never gives up entirely, it goes quiet": a target the operator has dealt with stops producing failures and drops out once the last one ages past 30 days, while a target that is still broken keeps producing them — the pack guard retries at worst weekly (§6.2) — and stays queued for exactly as long as it is genuinely broken. Nothing is dismissed by hand and no acknowledgement state is stored, so there is no second thing to keep correct. **Only a target still waiting for a file is queued.** The count and the window already express one rule — bounded attention — and this is another face of it: a failure history queues a target only while that target still has a gap to fill. A movie or an episode is queued while it is `wanted` and not `available`. A season holds no intent of its own (§4.1), so it is queued while at least one of its episodes is still `wanted` and not `available`. A season pack that hard-failed twice, fell back to per-episode grabbing exactly as §6.2 says it should, and was then fully acquired leaves at once rather than waiting out the 30 days — that is the system working, not a decision. A target that is still broken keeps producing failures and stays. The same rule applies on all three lanes and in both readers. `GET /api/queues/attention` (§9.3) and the `ntfy` notification (§9.5) are two views of one queue; filtering differently tells the operator two different stories on two channels. ## 6. Sourcing ### 6.1 Prowlarr, per-indexer Torznab `GET /api/v1/indexer` enumerates. Each indexer is then addressed at its own Torznab endpoint: ``` GET /{indexerId}/api?apikey=…&t=caps GET /{indexerId}/api?apikey=…&t=search&q=… GET /{indexerId}/api?apikey=…&t=movie&imdbid=… GET /{indexerId}/api?apikey=…&t=tvsearch&tvdbid=…&season=&ep= ``` Prowlarr's aggregate `/api/v1/search` is deliberately not used: Torznab is the stable standard rather than an internal UI API, it gives real RSS semantics, and per-indexer addressing keeps indexer identity in hand — which the per-tracker seeding rules need anyway. `t=caps` per indexer records which search modes each tracker supports. Not all do ID-based search; some are text-only. ### 6.2 Three triggers, three cost profiles | Trigger | Cost | Cadence | |---|---|---| | RSS sync | one call per *indexer*, independent of library size | ~10 min, never backs off | | Targeted search | one call per *wanted item* per attempt | exponential backoff | | Manual | one call, user-initiated | on demand | RSS is an empty-query Torznab call whose results are matched against the wanted list locally. Because its cost does not scale with the wanted list, every wanted item is matched against every RSS result forever — with one guard: the RSS lane skips a season pack for a season that already has episodes on disk, the same guard §14 applies to re-grabs. Both lanes agree, so a season does not behave differently depending on which lane sees a release first. A pack for a season with nothing on disk stays eligible. When a single episode cannot be found on its own, the escape hatch is the season release deck, not a lane exception. Targeted search backs off `1h → 6h → 1d → 3d`, capped at 7d, reset when the title's metadata changes. It never gives up entirely, it goes quiet. **The ladder runs from the failure, not the grab.** A failed season-pack grab quiets the pack lane on that same curve, and the rung is measured from the moment the grab entered `failed` — `grabs.failed_at`, the column §5.7's attention window reads — not from when it was sent. The two are usually minutes apart, but a torrent can stall on a dead swarm for five weeks before `ffprobe` condemns it at import. Measured from the grab, the whole ladder has already elapsed by the time the failure lands, so the lane retries the source that just failed at once, which is the one thing the backoff exists to prevent. The ladder's job is to stay off a source that has recently failed, and "recently" can only mean recently failed. One anchor covers both features. §5.7's window and this ladder ask the same question of the same event and read the same column; a target still broken keeps producing fresh failures, and each one both re-arms this backoff and holds the target in the attention queue. **Do not search before the release exists.** TMDB carries release dates; a movie with no digital release date gets zero targeted searches. This is the single largest source of wasted queries in Radarr and it is free to avoid. ### 6.3 Blacklist Keyed on infohash and normalised release name. Anything that hard-failed post-`ffprobe` is never grabbed again, including by RSS. A manual `blocked` flag stops targeted search for a title entirely while leaving RSS matching on. ## 7. Download and import ### 7.1 Transmission RPC at `10.6.10.45:9091`, no credentials. Labels are `movies-main`, `tv-kids` and so on — enough to find things in Transmission's own UI, and distinct from Radarr's existing `radarr`/`sonarr` labels so both stacks can run side by side. ### 7.2 Hardlink Verified: Radarr's only media bind is `/mnt/media-v2:/mnt/media`, one mount, one dataset, and the existing arrs hardlink-import today. So `link()` succeeds. Implementation still falls back to copy on `EXDEV` rather than trusting that forever — no configuration flag, no way to get it wrong. Hardlinking gives the library file and the seeding file independent names at zero extra disk. Copy would double storage for the entire seeding window, which at 4K is 40-80 GB per title. ### 7.3 Two lifecycles, deliberately decoupled The torrent and the library entry are separate state machines. Seeding obligation is **per tracker**, configured locally because Prowlarr does not expose tracker rules — `ratio` and `min_seed_time`. Set `seedRatioLimit` and `seedIdleLimit` on the torrent at add time and let Transmission enforce them. A reaper deletes torrents Transmission reports as done seeding. Consequently a hard-failed release is blacklisted and never imported, but its torrent keeps seeding until the obligation clears. Nothing is deleted early to satisfy the library. ### 7.4 Layout ``` /mnt/media/movies/main/Dune Part Two (2024) [tmdbid-693134]/ Dune Part Two (2024) [tmdbid-693134] - [2160p][WEB-DL][HDR10].mkv /mnt/media/tv/kids/Bluey (2018) [tmdbid-82728]/ Season 01/ Bluey (2018) - S01E02 - Hospital [1080p][WEB-DL][pt-PT].mkv ``` Media kind first, hard audience boundary second, people nowhere. - **Provider ID in the folder name** turns Jellyfin matching from fuzzy string guessing into exact lookup. - **Attribute tags come from `ffprobe`**, not from the release name, so they are true. The filename doubles as an audit surface: `ls` shows which files are DV or which of the kids' files are still English-only, with the app stopped. - **One folder per title even for a single file**, so sidecar subtitles and artwork stay contained and deletes are atomic. - **Release group is deliberately absent.** It is not a selection criterion and it makes filenames long enough to break a terminal. Changing a title's root relocates its title folder into the new root; roots are assumed to share one filesystem, so the move is a rename, never a copy. Changing a root's path is the same move over every title under it, and it is all or nothing: one folder that cannot move puts back the ones that already did and leaves the root's path alone, so the stored path always describes the disk. During transition, write into the existing roots so Jellyfin needs no reconfiguration and new content appears immediately. Radarr will not touch a folder it has no record of. ### 7.5 Jellyfin On successful import, call Jellyfin's refresh endpoint for the affected library. Its filesystem watcher misses things. One HTTP call at the end of import. ## 8. The reconcile loop There is no job queue. The database rows are the work list. A wanted episode with no file is a pending grab. A torrent past its seeding rule is a pending delete. A downloaded file not yet probed is a pending import. Every tick, compare desired state to actual state and act on the gap. This is idempotent and crash-safe by construction. Kill the process mid-grab and the next tick recomputes the same gap and continues. A job table would need retry counts, dead-lettering and reconciliation against Transmission anyway, because Transmission is an external system that changes underneath the app. Transient state — a search in flight, download progress — is in memory and rebuilt from Transmission on startup. Ticks are staggered: reconcile every 30 s, RSS every 10 min, metadata refresh daily, reaper every 5 min. ## 9. API and UI ### 9.1 API-first The HTTP API is the product surface; the web UI is a client of it with no privileged path. OpenAPI spec generated from handler annotations, served alongside the app, and used to generate the TypeScript client. Own schema first. Radarr-compatible endpoints are a **later, separate, lower-priority crate** (§9.4), not the primary shape. ### 9.2 Unified search One box. Two grouped result sets: **in library** first, **on TMDB** below. Both sets are titles — series and movies. Episode rows never appear, under any query, and there are no season rows. Enter on a TMDB result opens the add flow with root and policy pre-filled. The same box accepts a raw TMDB or IMDb ID, and a pasted magnet or `.torrent`, which skips to the manual-grab flow. There is never a moment where the user has to know whether they are searching or adding. Result rows are enriched: a poster thumbnail and a rating, under the same rules as title detail (§9.6) — images hotlinked from path fragments, the rating being TMDB's `vote_average` with its `vote_count`. A trailer chip renders per row and resolves only when clicked (§9.6). ### 9.3 Manual search results Radarr's manual search is unusable because the raw release name is the dominant column, pushing everything that actually decides the choice off-screen. Invert it. The policy engine has already classified every candidate: - **Three buckets.** `eligible` shown by default, sorted by score. `waived` (fails a soft rule, grabbable with one click that writes an override) and `rejected` collapse to a count, expandable. - **Columns are parsed attributes as chips** — score, resolution, source, HDR, audio languages, size, seeders. Fixed width, no horizontal scroll. - **Release name is secondary**, truncated, full string on expand. It is evidence for when you disagree with the parse, not the primary key. - **Every rejected row names the rule that killed it**, so over-strict filters are visible without reading names. Pre-grab, HDR and audio chips are best-effort from the name (§5.6). ### 9.4 Jellyseerr compatibility Jellyseerr stays. It already does Jellyfin user auth, discovery and request approval — none of which is the problem being solved, and rebuilding it doubles the project. A thin `arr-compat` crate exposes the slice Jellyseerr actually calls: ``` GET /api/v3/system/status GET /api/v3/rootfolder → the real roots GET /api/v3/qualityprofile → one fake profile per root GET /api/v3/tag GET /api/v3/movie existence check POST /api/v3/movie add GET /api/v3/movie/lookup ``` plus the `series` equivalents. Thin mappings onto the real domain, isolated in one crate that never leaks into `arr-core`. Lower priority than everything in §5-8. ### 9.5 Notifications `ntfy`, one topic per `Owner`. Three events only — Radarr's failure mode is notifying on everything and being muted within a week. - **Imported** → to the title's owners. The only good-news notification. - **Needs a decision** → to the operator alone. Entered the no-PT-source queue, or the needs-a-decision queue (§5.7). - **Broken** → to the operator alone. Prowlarr, Transmission or TMDB unreachable, disk full. Not notified: grabs, searches, downloads starting or finishing, soft fails. ### 9.6 Title detail One detail surface per kind: `/movies/{id}` and `/series/{id}` (#129). For a movie the release deck becomes a section of the page, and `/movies/{id}/releases` keeps resolving; series keeps its season-and-episode shape, seasons ordered newest-first within the series and episodes newest-first within each season — the seasons you are deciding about now are at the top, not after nine rows of back catalogue. **TMDB is the only metadata source.** The rating shown anywhere is TMDB's `vote_average` with its `vote_count`, rendered as amber stars (`--signal-warn` — the same state colour a wanted chip carries). No OMDb, no IMDb or Rotten Tomatoes scores — each would need a second upstream, a second key and a second thing that can be down. **Images are hotlinked** from `image.tmdb.org`. The API returns TMDB path fragments, never URLs; the browser composes the URL and chooses the size. No image proxy and no image cache in the service. **Rich detail is not persisted.** It is served through arr-meta's 24-hour response cache, which lives on disk in a directory alongside the database (§10), bounded by both age and total size (#158) — not the database itself, and not an image cache; images stay hotlinked as above. The single exception is `poster_path`, `backdrop_path` and `vote_average`, stored on `movies` and `series` and written by the daily metadata refresh (§8), so library views render without a TMDB call. **External links** are TMDB always, IMDb for movies, TVDB for series — all from ids the app already holds — plus a Rotten Tomatoes *search* link, which is a query URL, not a resolved title page. **Trailers resolve on click.** TMDB's search responses carry no videos, so a trailer key costs a detail call. Rendering one chip per title and resolving the one clicked keeps that cost at one call, and the 24h cache makes a repeat free. **Library view.** A poster grid by default with a list toggle; the list keeps the derived-status columns §4.2 built it around. Out of scope here, because they are the adjacent scope most likely to creep: watch providers, recommendations or similar titles, collections, person pages inside the app, review text. ### 9.7 The shell **The library is the homepage.** `/` renders the library view described in §9.6. It is what the operator opens the app to look at, so it is what the app opens on. **The signal chain is a settings section.** The four upstreams — tmdb, prowlarr, arr, transmission — and their lamps live inside `/settings`, and have no route of their own. Per-upstream health is something you check when something is wrong, not a homepage. **The master lamp stays on the rail**, so the at-a-glance read that the chain is healthy survives the move and no navigation is needed to get it. **The wordmark is a link home.** `arr` on the rail navigates to `/`. ## 10. Persistence SQLite via `sqlx`, compile-time-checked queries, migrations in `arr-db`. A few thousand rows, single writer. Postgres would buy nothing and cost a service. Policy lives in the database, not a config file — size targets and DV rules get tuned by hand during testing and a restart-to-reload loop gets old immediately. Only bootstrap settings (bind address, Prowlarr URL, Transmission URL, TMDB key, media root, TMDB response cache directory) come from config/env. Backup is `sqlite3 .backup` on a timer. ## 11. Crate layout Cargo workspace, `members = ["crates/*"]`, versions pinned once in `[workspace.dependencies]`, following `~/tea/maestro`. ``` arr-core domain types, policy engine, scoring no IO, no heavy deps arr-parse release name parsing no IO arr-meta TMDB client arr-indexer Torznab via Prowlarr arr-dl Transmission RPC arr-probe ffprobe wrapper arr-subs subtitle providers, translation, sync arr-db sqlx + migrations arr-api axum + OpenAPI arr-compat Radarr/Sonarr v3 shim for Jellyseerr arr-daemon reconcile loop, wires everything arr-e2e cross-process integration tests web/ Vite + TypeScript SPA, embedded via include_dir ``` The rule: `arr-core` and `arr-parse` hold the logic worth testing constantly and must not depend on axum, sqlx or reqwest. Everything expensive is downstream of them. Nothing is generic over media kind. Movies are built concretely, then TV concretely, and shared machinery is extracted only once both exist. An abstraction derived from one example fits one example. ## 12. CI Lints declared once in the root manifest: ```toml [workspace.lints.rust] unused_crate_dependencies = "warn" missing_debug_implementations = "warn" [workspace.lints.clippy] pedantic = { level = "warn", priority = -1 } unwrap_used = "warn" ``` Member crates carry only `[lints] workspace = true`. **Per-push gate**, target under 5 minutes: | Step | Tool | |---|---| | format | `cargo fmt --check` | | lint | `cargo clippy --all-targets -- -D warnings` | | unused deps | `cargo machete` (stable; `cargo udeps` needs nightly and a full rebuild) | | test | `cargo nextest run` | | frontend | `biome ci web/` and `tsc -b --noEmit` | **Off the gate**, scheduled: `cargo deny` for advisories and licenses. Coverage, if ever, likewise. Neither blocks a push. Total wall-clock on the self-hosted Gitea runner is an explicit constraint. The lever is caching, not step selection: cache `~/.cargo/registry`, `~/.cargo/git` and `target/`, keyed on `Cargo.lock` plus `rust-toolchain.toml`. Never build `--release` in the gate. **End-to-end tests, only at the seams that actually break:** - Prowlarr and TMDB — `wiremock` with recorded real responses as fixtures. Never live: trackers rate-limit, and it would leak credentials into CI. - Transmission — a real container as a CI service. RPC semantics are the most likely source of surprise and it starts in a second. - `ffprobe` — tiny committed clips, a few KB each. The Jellyfin LXC already has the right fixtures at `/srv/jellyfin-test`, including a real **DV Profile 5** clip. That is the test proving the policy engine rejects Profile 5 and accepts 8.1 — the subtlest rule in the system. E2E runs on `main` and on pull requests touching those crates, not every push. ## 13. Build order Each phase ends at something usable end to end. No phase is a refactor of the previous one. 1. **Skeleton** — workspace, CI gate, config, SQLite migrations, health endpoint, embedded empty SPA. 2. **Parse and score** — `arr-parse` and `arr-core` against fixture release names. Pure, fast, heavily tested. No network. 3. **Read-only sourcing** — TMDB lookup, Prowlarr enumeration and search, classified results over the API. Still grabs nothing. 4. **Movies, end to end** — add a movie, grab, download, `ffprobe`, hardlink, rename, Jellyfin refresh, seeding reaper. The first real cutover test is one movie Radarr does not know about. 5. **UI** — unified search, manual search buckets, library views, the queues. 6. **TV** — seasons, episodes, `auto_track`, per-episode versus season-pack grabbing, derived status. 7. **Owners and notifications** — tags, per-person ntfy topics, filtered views. 8. **Jellyseerr compat** — `arr-compat`. 9. **Subtitles** — replaces Bazarr. See §15. Movies before TV because TV adds season packs, air-date calendars and per-episode state on top of an otherwise identical pipeline. Doing it second means that pipeline is already proven. ## 14. Open questions - **Remux playback.** Whether a 4K remux streams cleanly to the Shield is untested. The usual failure is audio, not bitrate: BluRay remuxes carry TrueHD/DTS-HD MA, and if the Shield cannot bitstream that downstream, Jellyfin transcodes audio and playback stutters while video direct-plays. Test before fixing the 4K size ceiling in §5.5. The outcome changes the conclusion from "remuxes are bad" to "remux audio needs a downmix". - **Size band numbers** in §5.5 are placeholders pending that test. - **Season-pack re-grab.** When an airing season completes, the episodes are already present individually. Nothing re-grabs the pack, and per §6.2 the RSS lane obeys the same guard — it skips packs for any season with episodes on disk. Whether a re-grab is ever wanted remains unresolved and deliberately deferred. ## 15. Subtitles Replaces Bazarr. Phase 9 in §13; the `arr-subs` crate in §11. **Wanted set.** Global, not per root. Two languages are separately wanted for every media file: Portuguese — pt-PT preferred, pt-BR accepted — and English. A file is satisfied for a language when a subtitle in it exists, embedded or as a sidecar. This is deliberately unlike §5.2's audio rules, which attach to a root: subtitles carry no blacklist there and none here. pt-BR subtitles are always fine. **Embedded tracks.** An embedded subtitle track satisfies its language. Text-format tracks (`subrip`, `ass`, `mov_text`) are additionally extracted to a sidecar SRT, because an extracted track is a legal translation source. Image-format tracks (PGS on BluRay, VobSub on DVD) carry bitmaps, not text: they satisfy viewing but can never feed a translator, and arr does not OCR them. `arr-probe` already reports subtitle tracks with resolved languages; the format is the new fact it must carry. **Providers.** OpenSubtitles.com and Podnapisi, behind one trait. **Ranking.** A `moviehash` match wins outright. Then an exact release-name match, then same release group or same source, then uploader rating and download count as tiebreakers. Every rejected candidate names the rule that killed it, so the manual view described in §9.3 works unchanged for subtitles. **Forced and SDH.** A forced track covers only foreign-language lines and on-screen signs; it never satisfies a want and arr never goes looking for one. An SDH track is complete and satisfies, ranked below a plain subtitle. Neither gets its own sidecar name. A language is satisfied by exactly one sidecar, so `