Decisions on EdS

ADR-0001: The Stand Renders Effects

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0001: The Stand Renders Effects Locally and Never Receives Frames


Status	Accepted
Date	2026-09-07
Scope	What travels from `lightd` to a stand, and where animation happens.
Backfilled	Decided with the first firmware and argued in `firmware/lp-stand/README.md`; written up here on 2026-10-10.
Related	ADR-0002, Scene Descriptor

Context

The stand is an ESP32 driving an addressable strip over WiFi from a broker it does not control. The light has to look deliberate at all times, including when the network is slow or gone, and the stand is meant to sit on a shelf unattended.

ADR-0002: Gamma Belongs to the Firmware

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0002: Gamma Belongs to the Firmware, Not the Wire


Status	Accepted
Date	2026-09-07
Scope	Which layer makes which color decision between a cover image and the strip.
Backfilled	Decided with the first vertical and argued in the project READMEs and Boundaries; written up here on 2026-10-10.
Corrected	2026-10-13: the consequence about OKLab said the conversion is implemented three times, in Python, Go and C. It is in two, and never was in the firmware. The decision is unchanged.
Related	ADR-0001

Context

A color passes through three programs on its way from a sleeve to a strip: palette extracts it, lightd turns swatches into a scene, and the firmware drives the LEDs. Several corrections have to happen somewhere along the way — rejecting dull swatches, boosting chroma, mapping into the strip’s gamut, and gamma, because WS2812 output is linear in duty cycle and perception is not.

ADR-0003: The Broker Is Deevnet IoTaaS's

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0003: The MQTT Broker Is Deevnet IoTaaS’s, Not a Tenant VM


Status	Accepted
Date	2026-09-07
Scope	Where EdS’s MQTT broker runs, and so how devices and services meet.
Backfilled	Decided when the tenant was first written and argued in `infra/deevnet-tenant-eds/README.md`; written up here on 2026-10-10.
Related	Deevnet ADR-0001, ADR-0003 and ADR-0012 (deevnet-docs)

Context

EdS’s services run on a workload in its own tenant on Deevnet IoTaaS. Its devices are ESP32s on Deevnet IoTaaS’s IoT network. Both need a broker.

ADR-0004: Firmware Secrets Are NVS-Only

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0004: Firmware Secrets Are NVS-Only, and the Broker’s CA Is Provisioned


Status	Accepted
Date	2026-10-10
Scope	Where a device’s WiFi key, broker password and broker CA come from.
Related	CHG-0001, Provisioning a Stand

Context

The stand needs a WiFi key and a broker password, both issued by the EdS tenant, and the CA that the broker’s certificate is verified against. The repository is public, and the firmware image gets built, cached and copied.

ADR-0005: Device Events Over MQTT

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0005: A Device Reports Key Events Over MQTT, Not Its Serial Log


Status	Accepted
Date	2026-10-10
Scope	How an EdS device says what it is doing once the USB cable is gone, and how that is read.
Extended by	ADR-0017: an agent Pi is registered as a device and reports the same way
Related	CHG-0001, Deevnet ADR-0027 and CHG-0021 (deevnet-docs), MQTT Topics

Context

A stand on a shelf has no console. It fails soft by design, which makes its failures quiet: one that keeps showing the last good scene looks, from the room, exactly like one that was sent nothing.

ADR-0006: Now Playing Is a Bus of Small Drivers

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0006: Now Playing Is a Bus of Small Drivers Behind One Contract


Status	Accepted
Date	2026-10-10
Scope	How EdS learns what is playing across several players, and how that knowledge reaches whatever reacts to it.
Extended by	ADR-0020: a controller may send a command for the current track, and a driver that can carry one out reads its own command topic
Related	ADR-0003, ADR-0007, ADR-0008, and one record per player: 0011, 0012, 0013, 0014

Context

The stand lights from a cover image, but nothing tells EdS what is playing. lightd has carried POST /v1/cover since the first vertical as “the interface the future album-cover resolver will call”; this is what sits upstream of it.

ADR-0007: Drivers Are Portable Go

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0007: Drivers Are Portable Go, in One Agent Binary


Status	Accepted
Date	2026-10-10
Scope	The language and packaging of the now-playing drivers and backend.
Related	ADR-0006

Context

The players run on Windows 11, which pulls toward Windows tooling. But development happens on a Mac against the Deevnet Mobile site, some drivers will run on a Raspberry Pi and some on the tenant workload, and lightd is already Go.

ADR-0008: nowplayd Picks the Track and Guarantees the Fields

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0008: nowplayd Picks the Current Track and Guarantees Title, Album and Art


Status	Accepted
Date	2026-10-10
Scope	What turns several sources’ states into one current track, and who is responsible for the fields subscribers rely on.
Extended by	ADR-0016: a source can be named as reported without its cover, and then the promise of art does not apply to it
Related	ADR-0006, ADR-0009

Context

Several drivers may report at once: a paused iTunes, a Spotify playing on a phone. Subscribers want one answer. They also need a title, an album and a cover, and the drivers cannot all supply those: TIDAL through Last.fm arrives with no art, and a locally read TIDAL has no album.

ADR-0009: lightd Takes Covers From a Topic

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0009: lightd Takes Covers From a Topic as a Second Input


Status	Accepted
Date	2026-10-10
Scope	How the current track’s cover reaches `lightd`.
Extended by	ADR-0019: a cover may arrive with the name of a look, which `lightd` draws in place of the cover’s own colors
Related	ADR-0002, ADR-0008

Context

nowplayd publishes the current cover as image bytes on eds/nowplaying/current/art. lightd turns image bytes into a scene, and today takes them only over HTTP, at POST /v1/cover. Something has to carry the bytes from the topic to lightd.

ADR-0010: A Dual-Homed Pi Relays the Home LAN

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0010: Home-LAN Drivers Reach the Broker Through a Dual-Homed Mobile Pi


Status	Accepted
Date	2026-10-10
Scope	How a driver that must be near a player on the home LAN reaches the broker at the Deevnet Mobile site.
Extended by	ADR-0015: the image is EdS’s own, and a relay is a way of configuring it
Related	ADR-0003, ADR-0006, the Deevnet network segmentation standard (deevnet-docs)

Context

The Windows PCs that run iTunes and MusicBee sit on a home LAN. The broker is inside the Deevnet Mobile site. There is no path from the home LAN into the site, and the site’s workloads cannot reach private addresses outside it. The iTunes and MusicBee drivers speak network protocols to their players, and pairing with iTunes needs multicast, so they have to be on the players’ LAN.

ADR-0011: iTunes by Remote Pairing

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0011: iTunes Is Read by Remote Pairing, the Way the Phone Remote Does It


Status	Accepted 2026-10-10, after pairing with the real iTunes; see Evidence. Opened the same day as `Proposed`
Date	2026-10-10
Scope	How the iTunes driver learns of track changes and gets artwork.
Extended by	ADR-0020: the pairing is also used to play, pause, skip and set the volume
Related	ADR-0006, ADR-0007, ADR-0010

Context

The PCs run classic iTunes for Windows, not the Microsoft Store build and not the newer Apple Music app. A phone remote app already sees and controls it, after a one-time pairing and with no Apple ID sign-in. That pairing has to keep working for as long as Apple supports it.

ADR-0012: Spotify by the Web API

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0012: Spotify Is Read From the Account, Through the Web API


Status	Accepted 2026-10-11, once the driver had run against the account; two observations are still wanted, under What would settle it
Date	2026-10-10
Scope	How the Spotify driver learns what is playing.
Amended	2026-10-11, before it was accepted: where the driver runs, how it is authorized, which devices count, and that it takes no artwork. The text below is the amended decision; What changed lists the differences
Extended by	ADR-0031: the driver takes the album’s picture after all, from the answer it already asks for. ADR-0032: the authorization also allows changing playback, and the driver carries out commands
Related	ADR-0006, ADR-0007, ADR-0016

Context

Spotify knows what an account is playing wherever it plays: start a track on the desktop and the phone shows it. Spotify must also work when the rack is away from the house, which rules out anything that depends on the home LAN.

ADR-0013: MusicBee by the Remote Plugin's Protocol

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0013: MusicBee Is Read Through the MusicBee Remote Plugin’s Protocol


Status	Proposed — the protocol has been read and does what is needed; it has not been tried against a real MusicBee. See What would settle it
Date	2026-10-10
Scope	How the MusicBee driver learns of track changes and gets artwork.
Related	ADR-0006, ADR-0007, ADR-0010, ADR-0011

Context

MusicBee plays local files and has no cloud. Anything that reads it runs on or near the PC. Its extension point is a plugin: a .NET DLL loaded into MusicBee, with a notification when the track changes.

ADR-0014: TIDAL by Last.fm

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0014: TIDAL Is Read Through Last.fm, Because Nothing Better Is Offered


Status	Proposed — until it has been tried against the account; see What would settle it
Date	2026-10-10
Scope	How the TIDAL driver learns what is playing.
Priority	The lowest of the four players, by the owner’s choice. Built last.
Related	ADR-0006, ADR-0007, ADR-0012

Context

The wish was for TIDAL to work like Spotify: ask the account, from the cloud, with nothing on the PC, so that it also works away from home.

ADR-0015: EdS Builds Its Own Pi Images

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0015: EdS Builds Its Own Pi Images, on Deevnet IoTaaS’s Base


Status	Accepted
Date	2026-10-10
Scope	Where the definition of an EdS Raspberry Pi image lives, what it is built from, and what “the relay” is.
Extends	ADR-0010, which decided there would be a dual-homed Pi and did not say whose image it would run
Related	ADR-0004, CHG-0002

Context

The Pi that carries now-playing reports from the home LAN to the broker needed an image. Deevnet IoTaaS has an image factory that builds Raspberry Pi images, and the first relay image was built there, as a new variant beside Deevnet IoTaaS’s own.

ADR-0016: A Source Can Be Reported Without Its Cover

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0016: A Source Can Be Reported Without Its Cover, and Spotify Is


Status	Accepted
Date	2026-10-11
Scope	Whether everything that is reported as playing also lights the stand.
Extends	ADR-0008, which promised that `current` carries a cover whenever something is playing
Extended by	ADR-0028: a source can also be reported with its cover and still not lit, by a look that says so. ADR-0031: Spotify is no longer reported this way. It has its cover, and is kept off the stand as iTunes is; the setting remains, with no source in it
Related	ADR-0009, ADR-0012

Context

The stand was built to stand beside a record that is playing. iTunes plays a library of albums the owner chose, and the stand follows it.

ADR-0017: An Agent Pi Is a Registered Device

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0017: An Agent Pi Is a Registered Device, and Reports Its Events Like One


Status	Accepted
Date	2026-10-11
Scope	How the now-playing agent’s key events reach the tenant’s log store, and what the Pi it runs on is to the tenant.
Extends	ADR-0005, which gave devices a way to report and said a program that is not a device “needs another route”
Related	ADR-0015, ADR-0010

Context

The stand reports its key events to the tenant’s log store, and they are read on a dashboard. The agent Pi reported nothing: what it saw playing, and whether its drivers were working, was in its own journal, reached by SSH through the Builder.

ADR-0018: A Console of EdS's Own

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0018: EdS Has a Console of Its Own, Fed From the Bus, and It Only Looks


Status	Accepted 2026-10-11, once it had been watched in a browser on the site with tracks changing
Amended	2026-10-11, before it was accepted: served over TLS, not in the clear. When this was written nothing on the site would certify a name a tenant serves; Deevnet ADR-0037 has since given tenants a CA to ask. CHG-0007
Date	2026-10-11
Scope	Where a person looks to see what EdS is doing: what is playing, what the stand is showing, and whether the parts are up.
Extended by	ADR-0039: its first control, which switches the stand between records and every source
Related	ADR-0005, ADR-0006, ADR-0009, ADR-0016

Context

What EdS is doing was visible in three places, none of them a picture: the tenant’s Grafana dashboard, which lists events; mosquitto_sub; and the services’ journals. The stand has no LEDs attached yet, so nothing at all showed its colors.

ADR-0019: An Album Can Have a Look of Its Own

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0019: An Album Can Have a Look of Its Own, Named on the Music Side and Drawn on the Light Side


Status	Proposed — until the first one has been seen on the stand
Date	2026-10-11
Scope	How one particular album gets a scene that is not derived from its cover, without the part that makes scenes learning what an album is.
Extends	ADR-0009, which gave `lightd` covers and kept tracks and albums on the other side of the topic
Extended by	ADR-0028: a look can name no cover, and is then the look of there being none. ADR-0030: a single piece of music can have one too, by its title
Related	ADR-0008, ADR-0001

Context

Every scene so far is made the same way: the cover’s colors, picked by palette, turned into a scene by lightd. That is right for almost every record and wrong for a few. The Dark Side of the Moon is a black sleeve with a thin spectrum across it. The colors a fair extraction finds on it are not what anyone would light a room with for that album, and what they would light it with is obvious: the spectrum.

ADR-0020: A Touch Screen That Can Change What Plays

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0020: A Touch Screen Shows the Cover and Can Change What Plays, by Asking nowplayd


Status	Proposed — until a button on the screen has paused the real iTunes; see What would settle it
Date	2026-10-11
Scope	A second device, a small touch screen, that shows the cover of what is playing and has five buttons: play or pause, previous, next, volume up, volume down. This is the first thing in EdS that changes anything outside itself.
Extends	ADR-0006, in which a driver reports and reads nothing, and ADR-0011, which paired with iTunes as a remote and used the pairing only to read
Extended by	ADR-0032: Spotify’s driver carries the commands out too; ADR-0040: a sixth command names an album, and goes to iTunes whatever plays
Related	ADR-0008, ADR-0010, ADR-0016, ADR-0018, which said controls would be a decision of their own

Context

The stand shows a record’s colors. A screen beside it can show the cover itself, and a screen that can be touched is the obvious place for the few controls a listener reaches for.

ADR-0021: The Turntable Is Identified by Listening

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0021: The Turntable Is Identified by Listening, With a Recognizer That Can Be Replaced


Status	Proposed — until a record on the platter has lit the stand; see What would settle it
Date	2026-10-11
Scope	A third driver in `npagent`, `turntable`: it listens to the amplifier’s line-level output on the agent Pi, has a recognizer name what it hears, and reports that as a source on the now-playing bus.
Extends	ADR-0006, which said a turntable that identifies its record would be one more driver, and ADR-0007
Related	ADR-0008, ADR-0012 and ADR-0014, which each declined an unpublished interface; ADR-0015, ADR-0017

Context

The stand was built to stand beside a record that is playing. So far it follows iTunes, because iTunes can be asked what it is playing and a turntable cannot.

ADR-0022: The Owner's Collection Names the Record

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0022: For a Source That Plays the Owner’s Records, the Owner’s Collection Names the Record


Status	Proposed — until a record on the platter has been shown with its own sleeve; see What would settle it
Date	2026-10-12
Scope	How nowplayd completes a track from a source that plays physical records: it asks the owner’s collection at Discogs before any catalog, and the collection’s answer replaces the album the source named.
Extends	ADR-0008, in which a known album is never renamed. For the sources named here, it is.
Related	ADR-0021, which left this open; ADR-0016, the other setting that treats named sources differently

Context

The turntable driver names a track by what it sounds like. A recording is pressed on many records - the album, its reissues, compilations, box sets - and nothing in the sound says which. The recognizer names an album anyway. On the bench it called one track of Chicago Transit Authority a box set, and a track of No Jacket Required a singles collection.

ADR-0023: A Source That Is Switched On Holds the Stand

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0023: A Source’s Equipment Can Say It Is On, and a Source That Is On Holds the Stand


Status	Proposed — until the beacon has been timed on the switch it shares and a record has been held through its silences; see What would settle it
Date	2026-10-12
Scope	How EdS knows the turntable is switched on: a small device on the same switched outlet, whose connection to the broker is the whole of what it says. And what nowplayd does knowing it.
Extends	ADR-0008, whose rule now has one thing before it. ADR-0018: the console reads one more topic, and still only looks.
Related	ADR-0021, whose driver this is for and whose account of the wiring this corrects; ADR-0016 and ADR-0022, the other settings that treat named sources differently

Context

The turntable driver (ADR-0021) reports what it hears, and three things it cannot hear are in the way.

ADR-0024: Paused Long Enough Is Not Playing

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0024: A Track Left Paused Is Not Playing for Ever, and a Room With Nothing Playing Is Dim


Status	Proposed — until it has been seen in the room; see What would settle it
Date	2026-10-12
Scope	What nowplayd says when the current track has sat paused, or nobody is reporting; how that reaches the stand; what the stand shows then.
Extends	ADR-0008, which left “what a subscriber does with stopped” to the subscriber and “paused on B is more use than silence” without an end. ADR-0009: an emptied cover topic now means something to lightd.
Extended by	ADR-0028: the idle scene is for a room where something is switched on; with nothing switched on, a room with nothing playing is dark
Related	ADR-0016, whose “no cover sent” this must not be mistaken for; ADR-0023, whose held source is left alone; ADR-0020, whose play button must go on working

Context

Pause iTunes and walk away, and the stand goes on showing the album for as long as nothing else plays: hours, overnight. The console says “Paused on iTunes” over the same sleeve. Neither is false, and neither is what the room is doing, which is nothing.

ADR-0025: Current Says When There Are No Controls

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0025: The Current Track Says When There Is Nothing a Controller Could Do


Status	Proposed — until the screen has been touched with a record playing; see What would settle it
Date	2026-10-12
Scope	One optional field in `current`, said by nowplayd, and what the cover screen does with it.
Extends	ADR-0020, which noted that “a source that takes commands does not say so anywhere”. Now the current one does.
Related	ADR-0023, which made the turntable current for as long as it is on, and so made the screen’s buttons idle for as long

Context

Touch the cover screen and five buttons come up. With a record on the turntable every one of them does nothing: a command goes to the source that is current, and nothing can skip a record. Since ADR-0023 the turntable is current the whole time it is switched on, so that is the whole evening. The sleeve is what the screen is for then, and buttons over it are wrong twice: they hide it, and they lie.

ADR-0026: What Silence Means on the Turntable

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0026: A Gap Between Tracks Is Listened For, and a Silent Turntable Is Idle in Twenty Seconds


Status	Proposed — until a side has been played to it; see What would settle it
Date	2026-10-12
Scope	What the turntable driver does with a short silence, and how long nowplayd keeps the cover of a source that is stopped and held.
Extends	ADR-0021, whose “no single answer after that” now has one exception, and ADR-0024, whose five minutes for a stopped, held source is taken back
Related	ADR-0023, which is why a stopped turntable is still current; ADR-0022

Context

Two things were seen with records playing, on the day the driver went into service.

ADR-0027: What Is Asked of Outside Services Is Counted

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0027: What EdS Asks of Other People’s Services Is Counted, a Minute at a Time, and nowplayd Writes Its Counts to the Log Store Itself


Status	Proposed — until the counts have been seen on the dashboard; see What would settle it
Date	2026-10-12
Scope	Counting the calls `npagent` and `nowplayd` make to services that are not EdS’s; how those counts reach the tenant’s log store from each; the dashboard that reads them.
Extends	ADR-0005 and ADR-0017: the agent’s counts are one more event. A workload gets a route of its own, which neither gave it.
Related	ADR-0021, whose recognizer is the service least entitled to be leaned on; ADR-0022, ADR-0012, ADR-0008; Deevnet ADR-0027 (the tenant log store) and Deevnet ADR-0024 (dashboards)

Context

EdS asks things of services that are not its own. The turntable’s recognizer is Shazam’s, through an endpoint nobody offered. The owner’s collection is read from Discogs. Spotify’s Web API is polled. Covers are looked up at Deezer, the iTunes Search API, MusicBrainz and the Cover Art Archive.

ADR-0028: The Stand Is for Records

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0028: The Stand Is Lit for Records Only, and Is Dim Only While the Turntable Is On


Status	Proposed — until it has been seen in the room; see What would settle it
Date	2026-10-13
Scope	Which sources light the stand; what it shows when nothing is playing; and how lightd is told, without learning what a source is.
Extends	ADR-0024, whose idle scene is now for one case of two, and whose “it is not dark” no longer holds for the other. ADR-0019: a look can be named for there being no cover, and a look can be “light nothing”. ADR-0016: a second way for a source to be reported and not lit, which keeps its cover. ADR-0023: the switch says one thing more.
Extended by	ADR-0029: the stand is dark from power on too, and blinks when it cannot reach the broker. ADR-0030: one look is shown from a dark source too. ADR-0039: records-only is the default, and the console can switch the stand to every source
Related	ADR-0009, whose boundary this keeps; ADR-0026, whose dimmed room between two sides is the case that stays dim

Context

ADR-0024 gave a room with nothing playing a scene of its own: steady, warm, at 0.15. It chose that over dark because “a dark stand cannot be told from a dead one”.

ADR-0029: The Stand Starts Dark, and Blinks What Is Wrong

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0029: The Stand Starts Dark, and Says in Red Blinks How Far It Got


Status	Proposed — until each blink has been seen on the stand; see What would settle it
Date	2026-10-13
Scope	What the stand’s strip shows from power on until it is sent a scene; what it shows when it cannot get that far; and how it comes on and goes off.
Extends	ADR-0028, which made a room with nothing playing dark and left the stand’s own first seconds dim. ADR-0001: the stand now draws one thing nobody sent it.
Related	ADR-0005, the stand’s other way of saying what happened, which needs the broker this is for the lack of; ADR-0004, whose unprovisioned stand gets a blink of its own

Context

The firmware has always lit the strip the moment it had power: a dim warm white, “so an unconfigured or unreachable stand looks deliberate rather than broken”. Since ADR-0028 the stand is dark unless a record is on or the turntable is switched on. The warm white at power on is then the one time the stand is lit with nobody having asked: for a few seconds on every start, and for as long as the network is away.

ADR-0030: A Piece of Music Can Have a Look, From Any Source

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0030: One Piece of Music Can Have a Look of Its Own, Shown Whatever Plays It, and the Stand Learns to Scan


Status	Proposed — until it has been seen on the stand with the theme playing; see What would settle it
Date	2026-10-13
Scope	A look for a single track, known by its title; the one exception to the stand being lit for records only; and a sixth effect in the firmware to draw it with.
Extends	ADR-0019, whose looks were albums’. ADR-0028, whose dark sources now have one thing that lights them. ADR-0001: the stand has one more effect.
Related	ADR-0029, whose opening and closing are how this comes on and goes off in a dark room

Context

Its owner wants the stand to do what the front of KITT does while the theme from Knight Rider is playing: one red light, going from side to side.

ADR-0031: Spotify Is Shown, Like iTunes

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0031: Spotify Is Reported With Its Cover, and Treated as iTunes Is


Status	Proposed — until the driver has fetched a cover from the real account and the screen has shown it; see What would settle it
Date	2026-10-13
Scope	Whether Spotify’s track comes with a cover, where the cover is from, and what the stand does for it.
Extends	ADR-0012, whose driver took no artwork and now takes the album’s. ADR-0016: a source can still be reported without its cover, and Spotify no longer is. ADR-0028: Spotify becomes a dark source, as iTunes is.
Related	ADR-0030, whose “any source” this makes true of Spotify; ADR-0027, which counts the new requests; ADR-0018, whose page shows the cover

Context

ADR-0016 reported Spotify without a cover for two reasons. The owner did not want the lights to follow it. And Spotify’s developer pages have a line about not synchronizing its recordings with visual media, which ADR-0012 left to the owner’s judgment; fetching no artwork and lighting nothing stepped around it.

ADR-0032: Spotify Takes Commands

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0032: The Spotify Driver Carries Out Commands, With a Wider Authorization, for What Is Playing Here


Status	Proposed — until a press on the cover screen has paused Spotify; see What would settle it
Date	2026-10-13
Scope	Whether a controller’s command reaches Spotify, what the agent must be authorized for to carry it out, and which playback a command may touch.
Extends	ADR-0020, whose commands only iTunes carried out. ADR-0012, whose authorization only read.
Related	ADR-0031, which put Spotify’s sleeve on the cover screen above buttons that did nothing; ADR-0025, the other answer to that; ADR-0027

Context

Since ADR-0031 the cover screen shows what Spotify is playing, with the same five buttons it shows for iTunes. Pressed, they do nothing: nowplayd passes the command to the current source (ADR-0020), and Spotify’s driver reads no command topic. It was built to read, with an authorization that only reads, and both the code and the broker account say that changing it is a decision. This is that decision.

ADR-0033: The Whole Back End on One Pi

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0033: The Whole Back End Can Run on One Pi, as an Image Built on Deevnet’s Take-Home One


Status	Proposed — until a card has been built, booted and run; see What would settle it
Date	2026-10-13
Scope	Whether EdS can run with nothing of Deevnet IoTaaS behind it, on one Raspberry Pi; what that Pi’s image is built from; how its services run, where its secrets come from, and what its console presents.
Extends	ADR-0015: a second image, on a second base. ADR-0003: on Deevnet the broker is still Deevnet’s; on this Pi it is the Pi’s. ADR-0010: this Pi has one leg and is no relay. ADR-0018: the console’s certificate, where there is no Tenant Service CA.
Related	ADR-0017, ADR-0027, Deevnet’s runbook “Convert a Tenant to a Pi Image”

Context

EdS runs in two places. Four services (palette, lightd, nowplayd, the console) are containers on a workload in the EdS tenant. The agent, npagent, is on a Pi with a leg on the home network (ADR-0010). The broker, the log store and Grafana are Deevnet IoTaaS’s.

ADR-0034: Presence Is Heard, Not Remembered

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0034: Presence Is Heard, Not Remembered: Everything Says It Is There Every Thirty Seconds


Status	Proposed — until a stand unplugged across a broker restart is seen gray; see What would settle it
Date	2026-10-16
Scope	What `online` on a `…/status` topic means to whoever reads it: the console, and nowplayd for sources and beacons.
Extends	ADR-0023, whose consequence “a will needs a broker to send it” this removes. ADR-0018: the console now shows a part as up only if it has heard from it lately.
Related	ADR-0003, the broker that keeps retained messages across restarts

Context

Every part of EdS says it is there the same way: on connecting, it publishes online, retained, to its status topic, and leaves the broker a last will of offline, retained. The broker sends the will when it sees the connection die.

ADR-0035: Firmware Is Updated Through the Broker

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0035: Firmware Is Updated Through the Broker, and a Build That Cannot Reach It Is Undone


Status	Accepted 2026-10-17, after each device was updated over the air, one rolled back by itself, and one refused a build not its own; see Evidence. Opened 2026-10-16 as `Proposed`
Date	2026-10-16
Scope	How a new build reaches the stand, the cover screen and the beacon once each is in place; what a device does with one; and how a bad one is undone.
Extends	ADR-0029: the stand that cannot reach the broker still blinks, and now also gives up a new build that caused it.
Related	ADR-0003, why the broker sits where devices can reach it and nothing else of EdS can; ADR-0023, the beacon whose connection is its message; ADR-0034, the change that showed why this is wanted

Context

Every change to a device’s firmware has meant a USB cable: the stand unscrewed from its shelf, the beacon taken off its outlet, and the cover screen and the beacon taking turns on the Mac’s one serial port. ADR-0034 is the case in point: three devices to flash before three services could be deployed.

ADR-0036: The Screen Sleeps When Nothing Plays

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0036: The Cover Screen Sleeps When Nothing Has Played for Five Minutes, and Wakes for Music


Status	Accepted 2026-10-17 — slept and woken on the board (CHG-0026); see What would settle it
Date	2026-10-17
Scope	The cover screen’s firmware: when it turns its panel off, and what wakes it. Nothing on the bus changes.
Extends	ADR-0020, the screen itself
Related	ADR-0023, which makes a turntable that is switched off not heard; ADR-0024, which turns a long pause into stopped; ADR-0025, the last time the screen had to be told something without knowing a source; ADR-0029, the stand’s dark that is not a fault

Context

The cover screen is lit all the time. With nothing playing it shows a drawn record all night, to nobody. Its owner asked first for it to sleep when the turntable’s power, iTunes and Spotify are all gone, and to come back when one of them is.

ADR-0037: Hand-Kept Secrets Are Encrypted in the Repository

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0037: The Secrets Nothing Else Can Issue Are Kept Encrypted in the Repository, with sops and age


Status	Proposed — until the first secrets have moved and a second machine has read them; see What would settle it
Date	2026-10-18
Scope	Where EdS keeps the secrets it is the only holder of, and how its tools read them. Not the secrets Deevnet IoTaaS issues, and not those made on a device or a card.
Extends	ADR-0004, whose rule (no secret compiled in) stands; ADR-0022, whose token “is never committed” in plain text, and now is committed encrypted
Related	ADR-0033, whose first card went out without the Discogs token

Context

On 2026-10-18 the first backend card was written from a worktree, and went out with no Discogs settings. make card looks for deploy/discogs.env in the checkout it runs in; the file is gitignored, so a worktree never has it; and the script says “no Discogs settings” and carries on, as it should for an owner who has none. Nothing was wrong except where the secret lived.

ADR-0038: The Turntable's Album Is the Original One the Track Is On

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0038: The Turntable’s Album Is the One the Track Is On, and the Original One, Not a Time Since the Last


Status	Proposed — until a side of one record and then another by the same artist have been played; see What would settle it
Date	2026-10-19
Scope	Which album nowplayd names for a track heard on the turntable, and so which cover lights the room. The turntable driver, nowplayd’s resolution for the turntable, and the catalogs it asks.
Supersedes	ADR-0026’s “the driver remembers the album for ten minutes”; the rest of ADR-0026 stands
Extends	ADR-0022, the owner’s collection first, which stands and still comes first
Related	ADR-0019, whose album looks follow the album named; ADR-0027, which counts every call this adds

Context

On 2026-10-18, the first evening on the home Pi (CHG-0028), The Dark Side of the Moon was played, lifted, and Animals put on 52 seconds later. The recognizer named “Pigs On the Wing, Pt. 1” and then “Dogs”, which are right. The stand kept Dark Side’s rainbow look for both, because both were reported as on The Dark Side of the Moon.

ADR-0039: The Console Can Light the Stand for Every Source

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0039: The Console Can Light the Stand for Every Source, Until It Is Switched Back


Status	Proposed — until it has been switched both ways from the console in the room; see What would settle it
Date	2026-10-19
Scope	A switch on the console that lights the stand from iTunes and Spotify as well as records; where its state is kept; who may change it.
Extends	ADR-0018: the console gets its first control, and its account its second topic to publish. ADR-0028: records-only stays the default, and becomes a setting that can be changed while running.
Related	ADR-0020, whose commands are never retained; this is not one of them. ADR-0030, whose any-source look is unchanged. ADR-0009, whose boundary this keeps.

Context

The stand is lit for records only (ADR-0028): NP_DARK_SOURCES=itunes,spotify makes nowplayd give those sources’ covers the look dark, and lightd draws it as a dark stand. That is right for the room and stays the default.

ADR-0040: A Request Can Name an Album to Play

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0040: A Request Can Name an Album to Play, and iTunes Plays It From Its Own Library


Status	Proposed — until `play_album` sent to `nowplaying/command` has played an album through nowplayd and the driver (the driver’s half is shown); see What would settle it
Date	2026-10-23
Scope	A sixth command, `play_album`, that names an album rather than pressing a button; which player carries it out; and what the iTunes driver asks of the player’s library to do it. The first thing to send it is meant to be a voice (“Hey Ed, play Van Halen’s first album”), which is a decision of its own.
Extends	ADR-0020, whose five commands press buttons on whatever is playing, and ADR-0011, whose pairing has only read what plays and pressed those buttons
Related	ADR-0032, which added no command; ADR-0038, which already knows an artist’s original albums

Context

Every command so far is a button. It acts on whatever is playing, so a controller never needs to say where it is sent, and ADR-0020 made that a rule: a controller never names a source. A request to play an album is not a button. Nothing may be playing at all, and if something is, it may be the turntable, which takes no command.

ADR-0041: An Artist's Nth Album Is Counted in MusicBrainz

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0041: An Artist’s First Album Is Their First Studio Album, Counted in MusicBrainz


Status	Proposed — until an album asked for by its place has played; see What would settle it
Date	2026-10-24
Scope	What “Aerosmith’s first album” means, where the count comes from, and how the name it gives is made to match a library. Not how a request is heard, nor what plays it.
Extends	ADR-0038, whose idea of an original album, a studio album with nothing else to it, is the one counted here
Related	ADR-0040, which plays an album by its names and cannot ask the library what it holds; ADR-0022, the owner’s Discogs collection

Context

A request to play “Van Halen’s first album” has to become the names ADR-0040 plays an album by: the artist, and the album’s title, as the iTunes library writes them. The library cannot be asked which albums it has. Something else has to know the order of an artist’s albums.

ADR-0042: A Request Is Heard on the Workload

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0042: A Spoken Request Is Sent Whole to the Workload, Written Down There, and Made a Command


Status	Proposed — until a request said in the room has played its album; see What would settle it
Date	2026-10-24
Scope	How “Hey Ed, play Van Halen’s first album” travels from a microphone to `play_album`: what the device sends, where speech becomes words, and how words become a command. Not the device’s firmware, which is a decision of its own.
Extends	ADR-0040, whose command this sends, and ADR-0041, whose count it asks
Related	ADR-0003, the broker as the one way a device reaches EdS; ADR-0034

Context

The microphone is a reSpeaker Lite: an XMOS chip that cleans up what a room says, and a small ESP32-S3 beside it. The ESP32-S3 can listen for a wake word and keep a few seconds of audio. It cannot turn speech into words. A device can reach nothing of EdS’s but the broker (ADR-0003).

ADR-0043: The reSpeaker Runs Firmware of EdS's Own

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0043: The reSpeaker Runs Firmware of EdS’s Own, and Sends a Request When Its Button Is Held, Then When It Hears Its Name


Status	Proposed — until a request said into the reSpeaker has played its album; see What would settle it
Date	2026-10-24
Scope	What runs on the reSpeaker Lite’s XIAO ESP32-S3: how it hears, when it sends, and how it is provisioned and updated. Not what a request becomes, which is ADR-0042’s.
Extends	ADR-0042, whose `voice/<device>/utterance` this sends
Related	ADR-0004, ADR-0035, ADR-0034

Context

The reSpeaker Lite is two chips. An XMOS XU316 takes two microphones and gives one cleaned-up voice: echo cancelled, noise suppressed, beam steered. Its firmware (1.0.8, read over DFU on 2026-10-24) sends that over I2S to a XIAO ESP32-S3 (8 MB PSRAM, 8 MB flash), which came with an Arduino test sketch from Seeed. The XIAO is what can be programmed.

ADR-0044: The Music Is Turned Down While a Request Is Heard

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0044: The Music Is Turned Down While a Request Is Heard, and Comes Back by Itself


Status	Proposed — until a request said over the music has been heard to its end and played; see What would settle it
Date	2026-10-24
Scope	What happens to what is playing between the wake word and the answer: who says the device woke, which command lowers the music, and what brings it back.
Extends	ADR-0020, whose commands this adds two to; ADR-0042 and ADR-0043, whose request it is
Related	ADR-0040

Context

The reSpeaker’s XMOS chip cancels the echo of its own speaker, not of the stereo. With an album playing beside it, a request asked over the music was heard as speech until its six-second limit, sent at twice the size, and written down with the music in it (CHG-0037). Smart speakers lower their music while they listen. EdS’s music comes from players EdS controls.

ADR-0045: An Nth Album Not Owned Is the Next One That Is

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0045: An Artist’s Nth Album, When the Library Does Not Have It, Is the Next of Theirs It Does


Status	Proposed — until a first album the library lacks has been asked for and the next one played; see What would settle it
Date	2026-10-24
Scope	What “Genesis’ first album” plays when the owner’s library does not have From Genesis to Revelation.
Extends	ADR-0041, whose count this goes on along; ADR-0040, whose command gains alternatives

Context

“Genesis’ first album” was heard right, twice, and counted right: From Genesis to Revelation, 1969. The owner’s iTunes has it as its reissue, And the Word Was…, and so was asked for a title it has not got. With nothing matched it played the band’s other songs from Abacab, the first by name, which the driver rightly took for a miss; where nothing at all matches, having emptied its queue, it stops. The library cannot be asked what it has (ADR-0040), so a miss is only found by trying.

ADR-0046: Requests Are Matched Against the Owner's Library

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0046: Requests Are Matched Against the Owner’s Library, as Its XML Lists It


Status	Proposed — until the requests below play on the first try; see What would settle it
Date	2026-10-24
Scope	How voiced turns a heard artist and an album, or an album’s place, into the titles `play_album` names.
Extends	ADR-0041, whose count orders the library’s albums; ADR-0045, whose `instead` carries the library’s titles now

Context

Every miss on 2026-10-24 was a guess at how the library spells something. iTunes will not list its library to EdS (ADR-0040), so voiced asked for MusicBrainz’s titles and the driver checked what played. Each fix covered the miss before it: Genesis’ first is the reissue And The Word Was in the library; Skynyrd’s is Pronounced leh-nerd skin-nerd, not “(pronounced ’lĕh-’nérd ‘skin-’nérd)”; “Arrowsmith” and “Leonard Skinner” are how speech writes two bands down.

ADR-0047: voiced Asks eds-inventory

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0047: voiced Asks eds-inventory for the Owner’s Albums, in Place of Its Own Index


Status	Accepted 2026-10-24 — settled by CHG-0041
Date	2026-10-24
Scope	Where voiced finds the owner’s artists and albums when it turns a request into `play_album`. Not how it parses a request, or counts an artist’s albums in MusicBrainz, which are unchanged.
Extends	ADR-0046, whose matching moves to the inventory unchanged
Related	A Music Inventory, the proposal this begins; eds-inventory’s ADR-0002 and ADR-0003

Context

voiced matches requests against library.json, an index of the owner’s iTunes library that EdS makes from the XML and copies to voiced by hand (ADR-0046). Knowing what the owner has is an inventory concern, and eds-inventory now does it: it collects the same XML, keeps the same albums, and answers the four questions voiced asks with the same matching and thresholds, carried over from EdS’s internal/library.

ADR-0048: The Turntable Is Heard on Both Channels

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0048: The Turntable Is Heard on Both Channels, and One Gone Silent Is Said on the Console


Status	Proposed , until a side has played through with one channel unplugged; see What would settle it
Date	2026-10-25
Scope	How many channels the turntable’s driver listens to, what it decides from each, and how a channel gone silent is reported: a retained topic beside the source’s status, one event, and the console’s “Song detector” line. Not how silence, gaps or stops are timed, which is unchanged.
Extends	ADR-0026, whose silence is now the louder channel’s, and ADR-0034, whose “Song detector” pill gains a third color for an input heard on one side only
Related	ADR-0018, the console that only looks; ADR-0021, the driver; ADR-0017, the agent’s events

Context

On the evening of 2026-10-25 (about 01:34 UTC on the 26th) the stand went to standby in the middle of a side. A record was playing, the Eagles' Live, and the music could still be heard in the room. The turntable’s driver had heard twenty seconds below -55 dBFS and said stopped, as ADR-0026 has it do, and nowplayd dimmed the room a second later.

ADR-0049: A Device Holds Two Sites, and Is Told Which

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0049: A Device Holds Two Sites’ Settings, and Is Told Which to Use by a Message


Status	Proposed , until a device has been switched both ways and has undone a switch it could not complete; see What would settle it
Date	2026-10-26
Scope	What a device’s `creds` partition holds for more than one site, the keys it is held under, the message that switches a device from one site to the other, and what a device does when the switch fails. Not what is in a site’s settings, which is unchanged.
Extends	ADR-0004, whose partition now holds a second site’s secrets beside the first’s, and ADR-0035, whose topics, sender and undo-it-yourself rule a switch follows
Related	ADR-0033, the backend Pi that is the second site; ADR-0034, whose status says where a device is

Context

EdS’s devices now live at two sites. The tenant’s broker at Deevnet IoTaaS’s mobile site, on its IoT network, and the backend Pi at home, on the home network. Each site has its own Wi-Fi, its own broker accounts and, until the home Pi took a certificate from Deevnet’s Tenant Service CA, its own CA.

ADR-0050: How Each Track Was Completed Is Written Down

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0050: How Each Track’s Album and Cover Were Found Is Written Down, One Line a Track, and nowplayd Sends It to the Log Store


Status	Proposed , until the lines have been read on the dashboard from a side of a record; see What would settle it
Date	2026-10-27
Scope	What `nowplayd` writes down about completing a track: who named its album, where its cover came from, how long each step took and why one gave up; the owner’s collection being read; how those lines reach the tenant’s log store; the dashboard that reads them. Not how a track is completed, which is unchanged.
Extends	ADR-0027, whose `api.calls` was the only line `nowplayd` sent to the store
Related	ADR-0008, the completing; ADR-0022, the collection; ADR-0038, the original album

Context

On the evening of 2026-10-26 the turntable played “Over the Hills and Far Away”, the recognizer named it, and the stand did not follow it: the track was published with no cover. Finding out why took the journal. Houses of the Holy was not in the owner’s Discogs collection; naming its original album, through Deezer and then MusicBrainz at one call a second, used the whole lookup time; and the cover’s lookup had been given the same time, already spent. That last fault is fixed (eds#101). Nothing showed any of it.

ADR-0051: Spotify Is Switched On and Off From the Console

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0051: Spotify Is Switched On and Off From the Console, and Off Asks Spotify Nothing


Status	Accepted : switched both ways from the console’s page on the backend Pi, 2026-10-29 (CHG-0044); see What would settle it
Date	2026-10-28
Scope	A switch for the Spotify driver: where its state is kept, what “off” stops, who reads it, and the console’s second control.
Extends	ADR-0039: a second retained setting, and the console’s second control, which that record said would bring back the question of a login.
Related	CHG-0024, whose follow-up this is. ADR-0027, whose count shows the switch working. ADR-0020, whose commands are never retained; this is not one of them. ADR-0034.

Context

The Spotify driver asks Spotify what is playing every ten seconds, all day, whether or not anything plays. Its owner does not want that all the time, and does want Spotify followed sometimes.

ADR-0052: Each Pi's iTunes Pairing Is Kept, Encrypted, in the Repository

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0052: Each Pi’s iTunes Pairing Is Kept, Encrypted, in the Repository, and a New Card Starts Paired


Status	Accepted : a pairing kept, put on a card’s boot partition and taken by the first boot’s setup, with nobody at iTunes, 2026-10-29 (CHG-0045); see What would settle it
Date	2026-10-28
Scope	Where an agent’s iTunes pairing is kept between cards, how it reaches a new card, and one pairing per Pi. Not Spotify’s authorization, and not the other hand-kept secrets.
Extends	ADR-0037: its `secrets/`, its age key and `sops` are built here, for this first secret. A pairing is “made where it is used”, which that record leaves where it is made; this record says why a pairing is kept anyway. ADR-0011, whose consequence “lose it and pairing is repeated” this ends.
Related	ADR-0010, the relay Pi. ADR-0033, the backend Pi.

Context

The iTunes driver controls iTunes as a paired remote (ADR-0011). Pairing takes a person at the iTunes PC, typing a four-digit code that the Pi prints. What it leaves behind is one small file on the Pi, /var/lib/eds-npagent/itunes-pairing.json:

ADR-0053: A Home Pi Opens a Maintenance Leg for the Van

Mon, 01 Jan 0001 00:00:00 +0000

ADR-0053: A Home Pi Opens a Maintenance Leg for the Van, for a While, When Asked From Inside


Status	Proposed : until a window has been opened, used and closed on the backend Pi; see What would settle it. It takes effect when the Pi’s cable leaves DVNT-CORE
Date	2026-10-28
Scope	How the mobile site reaches an EdS Pi that lives at home: a Wi-Fi leg onto the home LAN, off unless opened, and what it admits. The day-2 jobs that use it are named here and decided elsewhere.
Extends	ADR-0010: a second leg, fenced, now off by default and opened for a time. ADR-0033: the backend Pi, now at home.
Related	CHG-0042, which moves the backend Pi home. CHG-0028, which chose one address at home. ADR-0052, one of the jobs. Deevnet ADR-0011, ADR-0013, ADR-0020 and ADR-0041, and Deevnet’s network segmentation standard.

Context

The backend Pi has moved home (CHG-0042), and others may follow. At home it is on the home LAN, DVNT-CORE (192.168.2.0/23, behind the home OPNsense). Its certificate, its tenant’s Terraform and the tools that look after it are on the mobile site, dvntm.