alexanderilyin · Oct 7, 2026 · Oct 7, 2026 · Oct 7, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -66,17 +66,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ### Changed
 
-- **Service: an image per devcontainer.json in sub-folders** ([ADR-0016](docs/decisions/0016-one-image-per-devcontainer-json.md)).
-  Each `.devcontainer/<folder>/devcontainer.json` is built with `--config` as an image of its own,
-  `<name>-<folder id>`, after the root config's `main` image. `POST /build` lists them all in a new
-  `images` field. The existing `image`/`registry`/`name`/`tag`/`imageBuildLogId` fields describe
-  `images[0]`, so a repository with a root config gets the same response as before. A repository with
-  only sub-folder configs used to fall back to `fallbackImage` (or fail); now it builds those configs,
-  and the top-level fields describe the first one. The fallback image is used only when there's no
-  config anywhere. Without a `fallbackImage`, that case is now a 400 (`no devcontainer.json found`)
-  instead of a 500. New optional request fields: `instances` builds only the listed ids (an unknown
-  id is a 400 listing the valid ones), and `dryRun` resolves the list and image names without building
-  or pushing. Two sub-folders that map to the same id are a 400.
 - **Breaking:** **Template: `hostRequirements` are minimums**, as in the Dev Container spec, instead of overriding
 - **Image: Node 24 LTS** (was Node 20, end-of-life since April 2026), base image pinned by digest.
   The npm package's `engines` is now `node >=22`.

diff --git a/charts/test-git-server/templates/deployment.yaml b/charts/test-git-server/templates/deployment.yaml
@@ -55,11 +55,6 @@ spec:
               {{- else }}
               mkdir -p "/work/{{ .name }}/$(dirname "{{ $configPath }}")"
               cp "/seed/{{ .name }}.json" "/work/{{ .name }}/{{ $configPath }}"
-              {{- /* The same devcontainer.json at more locations, for repos with several configs (one image each, ADR-0015). */}}
-              {{- range .extraConfigPaths }}
-              mkdir -p "/work/{{ $repo.name }}/$(dirname "{{ . }}")"
-              cp "/seed/{{ $repo.name }}.json" "/work/{{ $repo.name }}/{{ . }}"
-              {{- end }}
               {{- if .dockerfile }}
               {{- /* A real Dockerfile alongside devcontainer.json, for repos whose config uses "build": {"dockerfile": ...} instead of a plain "image" reference - the CLI resolves a relative dockerfile path against the config's own directory. */}}
               cp "/seed/{{ .name }}.Dockerfile" "/work/{{ .name }}/$(dirname "{{ $configPath }}")/Dockerfile"

diff --git a/charts/test-git-server/values.yaml b/charts/test-git-server/values.yaml
@@ -68,28 +68,6 @@ seedRepos:
     configPath: .devcontainer/gamma/devcontainer.json
     devcontainerJson: |
       { "image": "mcr.microsoft.com/devcontainers/base:alpine-3.20" }
-  # Several devcontainer.json files in one repo - one image per config
-  # (ADR-0015). extraConfigPaths copies the same devcontainer.json to more
-  # locations. The colliding one's two folders sanitize to the same id
-  # ("back-end"), which the service rejects before building anything.
-  - name: devcontainer-json-two-folders
-    path: location/devcontainer-json-two-folders.git
-    configPath: .devcontainer/frontend/devcontainer.json
-    extraConfigPaths: [.devcontainer/backend/devcontainer.json]
-    devcontainerJson: |
-      { "image": "mcr.microsoft.com/devcontainers/base:alpine-3.20" }
-  - name: devcontainer-json-root-and-folder
-    path: location/devcontainer-json-root-and-folder.git
-    configPath: .devcontainer/devcontainer.json
-    extraConfigPaths: [.devcontainer/tools/devcontainer.json]
-    devcontainerJson: |
-      { "image": "mcr.microsoft.com/devcontainers/base:alpine-3.20" }
-  - name: devcontainer-json-colliding-folders
-    path: location/devcontainer-json-colliding-folders.git
-    configPath: .devcontainer/Back_End/devcontainer.json
-    extraConfigPaths: [.devcontainer/back-end/devcontainer.json]
-    devcontainerJson: |
-      { "image": "mcr.microsoft.com/devcontainers/base:alpine-3.20" }
   # No devcontainer.json anywhere - the "not found at all" case, distinct
   # from (and adjacent to) the location-discovery repos above.
   - name: devcontainer-json-missing

diff --git a/docs/claude/notes/devcontainer-subfolder-config-discovery.md b/docs/claude/notes/devcontainer-subfolder-config-discovery.md
@@ -5,13 +5,6 @@ created: 2026-09-06
 
 # The sub-folder devcontainer.json location isn't auto-discoverable
 
-> **Superseded (2026-10-07)** by
-> [ADR-0016](../../decisions/0016-one-image-per-devcontainer-json.md). The
-> service now finds every sub-folder config itself, builds one image per
-> config with `--config`, and lists them in `POST /build`'s `images`. The
-> human choice moved to the caller (the `instances` filter), so no separate
-> discovery service is needed. The rest of this note is kept as history.
-
 ## What happened
 
 While building `devcontainer_config_discovery.feature`, `test-git-server`

diff --git a/docs/claude/plans/004-devcontainer-instance-list.md b/docs/claude/plans/004-devcontainer-instance-list.md
@@ -5,34 +5,20 @@ created: 2026-10-06
 
 # List support: `/build` returns a list of images → one Coder agent per image
 
-## Status (2026-10-07): Phase B step 1 (service) implemented; provider, module and template still open
-
-The service side is on `feat/multi-config-builds`, recorded in
-[ADR-0016](../../decisions/0016-one-image-per-devcontainer-json.md) (0013 was
-already taken). It differs from this plan in these ways:
-
-- **Additive, not breaking.** The 1.x API is stable
-  ([Versioning](../../project/versioning.md)), so the response keeps
-  `image`/`registry`/`name`/`tag`/`imageBuildLogId` and adds `images[]`. The
-  top-level fields describe `images[0]`: `main` when there is a root config,
-  else the first sub-folder item.
-- **400, not 422,** for an unknown `instances` id, an id collision, or an
-  empty id. The "no configs" case is also a 400, and only when there's no
-  `fallbackImage`. With one, the fallback is a single `main` item, used only
-  when no config exists at any of the three locations.
-- **ids** also drop leading and trailing `-`, so they stay valid in image
-  names and as DNS labels. Symlinked sub-folders are skipped.
-- **`instances: []`** fails the shape check. Use `null` or omit it for "all".
-- **Dry runs** count as `status="dry_run"` in `devcontainer_builder_builds_total`.
-- **New code:** discovery is in `service/src/config-discovery.ts`, and
-  `buildInstance()`/`devcontainerBuildArgs()` are in `build.ts`. BDD coverage
-  is in `devcontainer_config_discovery.feature`, with new seed repos
-  `devcontainer-json-{two-folders,root-and-folder,colliding-folders}`. Not run
-  yet, because it needs the cluster.
-
-Next: the provider's `images`/`instances`/dry run in `ModifyPlan` (step 2),
-then the module (step 3), the template (step 4), and the guide and README
-(step 5). Phase A (the template's list-of-one refactor) is still open.
+## Status (2026-10-07): abandoned
+
+Dropped before 1.0 by the maintainer. The service side (#60, ADR-0016) was
+merged and then reverted, so `images[]`, `instances` and `dryRun` never ship
+in a release and aren't part of the 1.x API. The template refactor (#65) and
+the provider's `images`/`instances` (provider #11) were closed unmerged.
+
+The blocker that settled it: Coder names an agent after its Terraform
+resource name (`ConvertState` in `provisioner/terraform/resources.go` fails
+with `duplicate agent name`), so a `for_each` over `coder_agent` can't give
+one agent per image.
+
+A repository whose only configs are in `.devcontainer/<folder>/` behaves as
+in 0.5.0: it falls back to `fallbackImage`, or fails.
 
 ## Context
 

diff --git a/docs/claude/plans/005-v1-readiness.md b/docs/claude/plans/005-v1-readiness.md
@@ -51,8 +51,8 @@ All merged on `main`, each verified as noted:
 - **Features:**
   - `customizations.kubernetes` for pod resources and node placement #59 (ADR-0015; scratch workspace:
     requests and limits applied, hostRequirements and placement ignored with warnings);
-  - one image per devcontainer.json in sub-folders #60 (ADR-0016, additive API; scratch release:
-    dry run, a folder build, a root build unchanged, unknown ids → 400).
+  - one image per devcontainer.json in sub-folders #60: reverted, the feature is abandoned (see
+    [plan 004](004-devcontainer-instance-list.md)).
 - **Tests:**
   - route tests and a fake registry #61: 87% → 94% lines, 74% → 88% branches, 129 unit tests;
   - BDD `request_validation` on the cluster: 53 of 53 scenarios.
@@ -76,10 +76,6 @@ All merged on `main`, each verified as noted:
 
 ## Still open before tagging
 
-- **Multiple configurations end to end:**
-  - provider `images`/`instances` (PR in progress);
-  - template Phase A, keyed by instance with `moved` blocks (PR in progress);
-  - then Phase B, which needs a provider release.
 - **Harbor tutorial** once rts #37 is applied, including whether `DELETE /image` by digest can remove
   another tag that shares it.
 
@@ -117,6 +113,4 @@ All merged on `main`, each verified as noted:
   `hostRequirements`. Needs: the service exposing it through `GET /devcontainer`, the provider's
   data source, and the template mapping (capped like today), plus an ADR.
 - **Harbor** (rts #37): a self-hosted registry, after which come private-registry tutorials.
-- **Multiple Dev Container configurations** ([plan 004](004-devcontainer-instance-list.md)):
-  - the service side can land additively (`images[]` next to today's single-image fields);
-  - the template side needs a provider release.
+- **Multiple Dev Container configurations:** abandoned ([plan 004](004-devcontainer-instance-list.md)).
diff --git a/docs/concepts/testing.md b/docs/concepts/testing.md
@@ -49,7 +49,7 @@ and per-domain reference pages.
 |---|---|
 | `health.feature` | Liveness/readiness signals, including a deliberately-never-ready pod |
 | `request_validation.feature` | `/build`'s up-front shape check, independent of whether the values are usable |
-| `devcontainer_config_discovery.feature` | Every devcontainer.json location the spec allows (root, `.devcontainer/`, `.devcontainer/<folder>/`), one image per config, `instances`, `dryRun`, and the 400s for an unbuildable list |
+| `devcontainer_config_discovery.feature` | The devcontainer CLI's real auto-discovery locations (root, `.devcontainer/`, *not* an arbitrary sub-folder) |
 | `devcontainer_config_content.feature` | A discoverable-but-unusable `devcontainer.json` fails clearly, including the `"build":{"dockerfile":...}` path |
 | `image_resolution.feature` | Name/tag/registry defaulting and mapping-rule resolution |
 | `registry_auth.feature` | Ambient vs. per-request registry push credentials against a real auth-enforcing registry |

diff --git a/docs/decisions/0016-one-image-per-devcontainer-json.md b/docs/decisions/0016-one-image-per-devcontainer-json.md
diff --git a/docs/decisions/index.md b/docs/decisions/index.md
@@ -31,7 +31,6 @@ change, never rewritten in place).
 | [0010](0010-command-output-capture.md) | Capture git/docker subprocess output to files instead of stdout | accepted |
 | [0011](0011-devcontainer-metadata-endpoint.md) | `GET /devcontainer`: merged Dev Container metadata, read from the image | accepted |
 | [0012](0012-dev-container-to-kubernetes-runtime-mapping.md) | Dev Container → Kubernetes runtime mapping | accepted (`hostRequirements` part superseded by [0014](0014-host-requirements-are-minimums.md)) |
-| [0013](0013-fallback-config-for-repos-without-one.md) | A fallback image for repositories without a devcontainer.json | accepted (sub-folder consequence superseded by [0016](0016-one-image-per-devcontainer-json.md)) |
+| [0013](0013-fallback-config-for-repos-without-one.md) | A fallback image for repositories without a devcontainer.json | accepted |
 | [0014](0014-host-requirements-are-minimums.md) | `hostRequirements` are minimums | accepted |
 | [0015](0015-kubernetes-customizations.md) | `customizations.kubernetes` for pod resources and node placement | accepted |
-| [0016](0016-one-image-per-devcontainer-json.md) | One image per devcontainer.json, listed in `POST /build`'s response | accepted |
diff --git a/docs/reference/CONFIGURATION.md b/docs/reference/CONFIGURATION.md
@@ -33,7 +33,7 @@ concern documented in
 | Clone timeout (seconds) | `--clone-timeout` | `CLONE_TIMEOUT_SECONDS` | `build.cloneTimeoutSeconds` | `600` |
 | Build+push timeout (seconds) | `--build-timeout` | `BUILD_TIMEOUT_SECONDS` | `build.timeoutSeconds` | `3600` |
 | Concurrent builds per instance | `--max-concurrent-builds` | `MAX_CONCURRENT_BUILDS` | `build.maxConcurrent` | `4` (`0` = no limit) |
-| Fallback image (repos without any devcontainer.json, not even in a sub-folder, [ADR-0013](../decisions/0013-fallback-config-for-repos-without-one.md)) | `--fallback-image` | `FALLBACK_IMAGE` | `build.fallbackImage` | *(unset — such builds fail with 400)*; the chart sets `mcr.microsoft.com/devcontainers/base:ubuntu` |
+| Fallback image (repos without a devcontainer.json, [ADR-0013](../decisions/0013-fallback-config-for-repos-without-one.md)) | `--fallback-image` | `FALLBACK_IMAGE` | `build.fallbackImage` | *(unset — such builds fail)*; the chart sets `mcr.microsoft.com/devcontainers/base:ubuntu` |
 | Sentry/GlitchTip DSN | `--sentry-dsn` | `SENTRY_DSN` | `sentry.dsn` | *(unset — error tracking off)* |
 | Service name | `--service-name` | `SERVICE_NAME` | `observability.serviceName` | `devcontainer-builder` |
 | Deployment environment | `--environment` | `DEPLOYMENT_ENVIRONMENT` | `observability.environment` | `development` |