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+# Narratio S3 Input and Archive Implementation Plan
+
+## 1. Purpose
+
+This document defines the implementation plan for adding S3-based audio input and S3 archival/promotion to `narratio`.
+
+The feature has two related responsibilities:
+
+1. **Input acquisition**: load source audio files from an S3 bucket into local working storage before transcription.
+2. **Archival and promotion**: after a successful run, upload the complete run record to S3 and promote selected outputs to stable session-level paths.
+
+The design preserves the existing stage-based architecture:
+
+```text
+prepare
+transcribe
+merge
+polish
+normalize
+trim
+analyze
+archive
+notify
+```
+
+The new S3 behavior should fit into the existing modular design:
+
+- `prepare` acquires input audio.
+- intermediate stages operate on the local workdir.
+- `archive` uploads successful run outputs and promotes configured artifacts.
+- external storage details remain behind a storage backend abstraction.
+- failed runs remain local for diagnostics and are not uploaded to S3.
+
+## 2. Finalized Design Decisions
+
+The following design choices are settled:
+
+```text
+S3 session prefix:
+  {root_prefix}/campaigns/{campaign}/sessions/{session_id}/
+
+Example:
+  dnd/campaigns/forsaken/sessions/2026-04-19/
+
+run_id format:
+  20260515T031522Z-a1b2c3d4
+
+local work path:
+  /var/lib/narratio/work/{campaign}/{session_id}/{run_id}/
+
+local spool path:
+  /var/spool/narratio/{campaign}/{session_id}/{run_id}/audio/
+
+S3 audio source:
+  audio already exists in S3 before narratio runs
+
+failed runs:
+  retained locally only; not uploaded to S3
+
+archive:
+  real final pipeline stage
+
+promotion:
+  performed during archive stage after all prior required stages succeed
+
+default promoted outputs:
+  transcripts/trimmed.json
+  artifacts/session_recap.md
+  current/manifest.json
+  current/run_id.txt
+
+raw WhisperX transcripts:
+  uploaded under runs/{run_id}/transcripts/raw/
+
+audio re-upload:
+  original source audio is not re-uploaded by archive by default
+
+current/run_id.txt:
+  written last as the effective S3 commit pointer
+```
+
+## 3. S3 Layout
+
+The canonical S3 layout should be:
+
+```text
+s3://{bucket}/{root_prefix}/campaigns/{campaign}/sessions/{session_id}/
+  audio/
+    speaker-1.flac
+    speaker-2.flac
+
+  transcripts/
+    trimmed.json
+
+  artifacts/
+    session_recap.md
+
+  current/
+    manifest.json
+    run_id.txt
+
+  runs/
+    {run_id}/
+      inputs/
+        session.yml
+        speakers.yml
+        glossary.yml
+        autocorrect.yml
+        pipeline.resolved.yml
+
+      transcripts/
+        raw/
+          speaker-1.json
+          speaker-2.json
+        merged.json
+        processed.json
+        normalized.json
+        trimmed.json
+
+      artifacts/
+        session_bounds.json
+        session_recap.md
+
+      reports/
+        seriatim.merge.report.json
+        audita.report.json
+        seriatim.normalize.report.json
+        seriatim.trim.report.json
+
+      config/
+        seriatim.generated.yml
+        seriatim.normalize.generated.yml
+        seriatim.trim.generated.yml
+        audita.generated.yml
+        scriptorium.bounds.generated.yml
+        scriptorium.session_recap.generated.yml
+
+      logs/
+        whisperx.*.log
+        seriatim.*.log
+        audita.*.log
+        scriptorium.*.log
+
+      manifest.json
+```
+
+### 3.1 Session Root
+
+The session root is:
+
+```text
+{root_prefix}/campaigns/{campaign}/sessions/{session_id}/
+```
+
+For example:
+
+```text
+dnd/campaigns/forsaken/sessions/2026-04-19/
+```
+
+The `campaigns/` path segment is intentional. It leaves room for future campaign-level material:
+
+```text
+dnd/campaigns/{campaign}/campaign.yml
+dnd/campaigns/{campaign}/glossary.yml
+dnd/campaigns/{campaign}/characters/
+dnd/campaigns/{campaign}/sessions/
+```
+
+### 3.2 Session-Level Paths
+
+The session-level root contains the durable, promoted, current view of the session:
+
+```text
+audio/
+transcripts/
+artifacts/
+current/
+runs/
+```
+
+The top-level `audio/` directory is the source of truth for original session audio. Audio is assumed already present in S3 and should not be re-uploaded by `archive` by default.
+
+The top-level `transcripts/` and `artifacts/` directories should contain only configured promoted outputs.
+
+### 3.3 Run-Specific Paths
+
+Each successful run is uploaded under:
+
+```text
+runs/{run_id}/
+```
+
+This contains the full run record:
+
+- materialized inputs
+- intermediate transcripts
+- raw WhisperX transcripts
+- tool reports
+- generated configs
+- logs
+- generated artifacts
+- manifest
+
+Inputs belong under `runs/{run_id}/inputs/`, not at the session root, because inputs are run-specific. A rerun may use different `speakers.yml`, `glossary.yml`, `autocorrect.yml`, `pipeline.resolved.yml`, Scriptorium prompts, trim settings, models, or runtime configuration.
+
+### 3.4 Current Pointer
+
+The effective commit pointer is:
+
+```text
+current/run_id.txt
+```
+
+This file should be written last during archive.
+
+`current/manifest.json` should also be written during promotion so consumers can inspect the current promoted run without first resolving the run directory.
+
+The archive stage should upload in this order:
+
+1. run record under `runs/{run_id}/`
+2. configured promoted outputs under top-level `transcripts/` and `artifacts/`
+3. `current/manifest.json`
+4. `current/run_id.txt` last
+
+This makes `current/run_id.txt` the closest practical S3 equivalent of an atomic session commit marker.
+
+## 4. Local Filesystem Layout
+
+The production local layout should be:
+
+```text
+/var/lib/narratio/
+  work/
+    {campaign}/
+      {session_id}/
+        {run_id}/
+          inputs/
+          audio/
+          transcripts/
+          artifacts/
+          reports/
+          config/
+          logs/
+          manifest.json
+          .lock
+
+/var/spool/narratio/
+  {campaign}/
+    {session_id}/
+      {run_id}/
+        audio/
+          speaker-1.flac
+          speaker-2.flac
+```
+
+For local development, these roots should be configurable. For example:
+
+```yaml
+workspace:
+  root: ./workspace
+
+spool:
+  root: ./spool
+```
+
+Resulting in:
+
+```text
+./workspace/work/{campaign}/{session_id}/{run_id}/
+./spool/{campaign}/{session_id}/{run_id}/audio/
+```
+
+## 5. Local Audio Handling
+
+The intended local flow is:
+
+```text
+S3 audio
+  ↓
+spool/audio
+  ↓
+work/audio
+  ↓
+transcribe
+```
+
+The `prepare` stage should:
+
+1. list `.flac` objects under the configured S3 audio prefix,
+2. fail clearly if none are found,
+3. download audio files into the spool directory,
+4. copy or materialize them into the run workdir `audio/`,
+5. record provenance in the manifest.
+
+The rest of the pipeline should use `work/audio/`, not S3 paths directly and not spool paths.
+
+Audio cleanup should be conservative in the first implementation. It is acceptable to add a config knob such as:
+
+```yaml
+spool:
+  delete_audio_after_archive: true
+```
+
+For v1, prefer retaining local workdir audio until the run has successfully archived. The source of truth remains S3, but local diagnostics are valuable during development.
+
+## 6. Configuration Design
+
+### 6.1 Storage Config
+
+Add or refine a storage section:
+
+```yaml
+storage:
+  s3:
+    bucket: "my-dnd-archive"
+    root_prefix: "dnd"
+    region: "us-east-1"
+    endpoint: ""
+    force_path_style: false
+```
+
+Requirements:
+
+- `bucket` is required when S3 input/archive is enabled.
+- `root_prefix` defaults to `dnd`.
+- `region` may be optional depending on SDK behavior.
+- `endpoint` is optional for S3-compatible storage.
+- `force_path_style` is useful for MinIO/Garage/S3-compatible backends.
+- Credentials must not be stored in config. Use standard AWS environment/profile/instance-role mechanisms.
+
+### 6.2 Workspace and Spool Config
+
+Use:
+
+```yaml
+workspace:
+  root: "/var/lib/narratio"
+
+spool:
+  root: "/var/spool/narratio"
+  delete_audio_after_archive: false
+```
+
+If existing `workspace.root` currently points directly to a work root, the implementation should either preserve the existing semantics or migrate carefully with documentation. The new layout should include campaign/session/run path segments.
+
+### 6.3 Session Config
+
+The session config should include campaign and session ID:
+
+```yaml
+session:
+  id: "2026-04-19"
+  campaign: "forsaken"
+```
+
+If the current config shape uses top-level `session_id`, either migrate to the nested shape with compatibility or maintain the current shape while ensuring both campaign and session ID are available to the path builder.
+
+### 6.4 S3 Audio Input Config
+
+Use relative audio prefix resolution:
+
+```yaml
+inputs:
+  audio_s3:
+    prefix: "audio/"
+```
+
+This resolves relative to:
+
+```text
+{root_prefix}/campaigns/{campaign}/sessions/{session_id}/
+```
+
+For example:
+
+```text
+dnd/campaigns/forsaken/sessions/2026-04-19/audio/
+```
+
+The prepare stage should fail if no `.flac` files are found under this prefix.
+
+Local audio input should continue working for development unless intentionally deprecated later.
+
+### 6.5 Archive Config
+
+Add an archive config section:
+
+```yaml
+archive:
+  enabled: true
+  upload_run: true
+
+  promote_artifacts:
+    - from: "transcripts/trimmed.json"
+      to: "transcripts/trimmed.json"
+      required: true
+
+    - from: "artifacts/session_recap.md"
+      to: "artifacts/session_recap.md"
+      required: true
+```
+
+If `promote_artifacts` is omitted, use the built-in default list:
+
+```yaml
+archive:
+  promote_artifacts:
+    - from: "transcripts/trimmed.json"
+      to: "transcripts/trimmed.json"
+      required: true
+
+    - from: "artifacts/session_recap.md"
+      to: "artifacts/session_recap.md"
+      required: true
+```
+
+Additionally, archive should always write:
+
+```text
+current/manifest.json
+current/run_id.txt
+```
+
+Those current-pointer artifacts are part of archive semantics and should not need to be listed in `promote_artifacts`.
+
+## 7. Run Identity
+
+`run_id` should be first-class.
+
+Use the format:
+
+```text
+YYYYMMDDTHHMMSSZ-xxxxxxxx
+```
+
+Example:
+
+```text
+20260515T031522Z-a1b2c3d4
+```
+
+Properties:
+
+- sortable by timestamp
+- human-readable
+- collision-resistant via short random suffix
+- safe for file paths and S3 keys
+
+The manifest should include:
+
+```json
+{
+  "campaign": "forsaken",
+  "session_id": "2026-04-19",
+  "run_id": "20260515T031522Z-a1b2c3d4",
+  "local_workdir": "/var/lib/narratio/work/forsaken/2026-04-19/20260515T031522Z-a1b2c3d4",
+  "s3_session_prefix": "dnd/campaigns/forsaken/sessions/2026-04-19/",
+  "s3_run_prefix": "dnd/campaigns/forsaken/sessions/2026-04-19/runs/20260515T031522Z-a1b2c3d4/"
+}
+```
+
+### 7.1 CLI Behavior
+
+Recommended behavior:
+
+```text
+run:
+  creates a new run_id unless --run-id is supplied
+
+resume:
+  uses --run-id when supplied
+  otherwise may discover latest local run for the campaign/session
+
+run-stage:
+  uses --run-id when supplied
+  otherwise may discover latest local run for the campaign/session
+```
+
+For safety, implementation may choose to require `--run-id` for `resume` and `run-stage` when multiple local runs exist.
+
+The exact CLI behavior should be documented.
+
+## 8. Manifest Changes
+
+Extend manifest data to include:
+
+- `campaign`
+- `session_id`
+- `run_id`
+- `local_workdir`
+- `local_spool_dir`
+- `s3_bucket`
+- `s3_session_prefix`
+- `s3_run_prefix`
+- archive status and promoted outputs
+- S3 source provenance for audio inputs
+- S3 destination records for archived outputs
+
+Audio input records should include:
+
+```text
+source = s3
+s3_bucket
+s3_key
+local_path
+size
+etag
+sha256 if computed
+```
+
+Use ETag as S3 metadata only, not as a reliable checksum.
+
+SHA-256 should be computed after download if practical.
+
+## 9. Storage Backend Abstraction
+
+S3 code should not leak into stages.
+
+Add or extend a storage backend interface with operations like:
+
+```text
+List(ctx, prefix) ([]ObjectInfo, error)
+Download(ctx, key, localPath) error
+Upload(ctx, localPath, key, metadata) error
+Exists(ctx, key) (bool, error)
+```
+
+Potential object metadata:
+
+```text
+key
+size
+etag
+last_modified
+```
+
+A future copy method may be useful, but v1 can upload from local paths.
+
+The `prepare` stage should use the storage backend to list/download audio.
+
+The `archive` stage should use the storage backend to upload run records and promoted outputs.
+
+Tests should use a fake storage backend, not real S3.
+
+## 10. Prepare Stage Changes
+
+The `prepare` stage should support both existing local audio workflows and the new S3 audio source.
+
+### 10.1 S3 Audio Flow
+
+When `inputs.audio_s3.prefix` is configured:
+
+1. compute the session root:
+   ```text
+   {root_prefix}/campaigns/{campaign}/sessions/{session_id}/
+   ```
+
+2. resolve the audio prefix:
+   ```text
+   {session_root}/{inputs.audio_s3.prefix}
+   ```
+
+3. list objects under that prefix
+
+4. filter to `.flac`
+
+5. fail clearly if no `.flac` files are found
+
+6. download each file to:
+   ```text
+   {spool.root}/{campaign}/{session_id}/{run_id}/audio/
+   ```
+
+7. copy or materialize each file to:
+   ```text
+   {workspace.root}/work/{campaign}/{session_id}/{run_id}/audio/
+   ```
+
+8. compute local checksums if practical
+
+9. record audio input provenance in manifest
+
+### 10.2 Local Audio Flow
+
+Existing local audio flow should continue to work unless intentionally changed later.
+
+If both local audio and S3 audio are configured, fail clearly unless a precedence rule is explicitly documented. Prefer requiring exactly one audio input source.
+
+## 11. Archive Stage
+
+The archive stage becomes a real stage.
+
+It should run after `analyze` and before `notify`.
+
+Archive should only upload successful runs.
+
+Since the normal runner is sequential, if any prior stage fails, archive will not run. If the user invokes `run-stage archive` manually, the archive stage should validate prerequisite stages before uploading.
+
+### 11.1 Archive Prerequisites
+
+For v1, require these stages to have succeeded before archive:
+
+```text
+prepare
+transcribe
+merge
+polish
+normalize
+trim
+analyze
+```
+
+If a stage is optional in a future config, this prerequisite list may become configurable. For now, hardcoded prerequisites are acceptable.
+
+### 11.2 Run Upload
+
+Upload the local workdir record to:
+
+```text
+{session_root}/runs/{run_id}/
+```
+
+Suggested mapping:
+
+```text
+workdir/inputs/       → runs/{run_id}/inputs/
+workdir/transcripts/  → runs/{run_id}/transcripts/
+workdir/artifacts/    → runs/{run_id}/artifacts/
+workdir/reports/      → runs/{run_id}/reports/
+workdir/config/       → runs/{run_id}/config/
+workdir/logs/         → runs/{run_id}/logs/
+workdir/manifest.json → runs/{run_id}/manifest.json
+```
+
+If reports currently live under `artifacts/`, implementation may either:
+
+1. keep that local layout and upload them under `runs/{run_id}/artifacts/`, or
+2. add a logical archive mapping into `runs/{run_id}/reports/`.
+
+Avoid disruptive local layout changes unless they are already easy and well-tested.
+
+### 11.3 Promotion
+
+For each configured promotion rule:
+
+```yaml
+- from: "transcripts/trimmed.json"
+  to: "transcripts/trimmed.json"
+  required: true
+```
+
+Upload:
+
+```text
+local workdir/transcripts/trimmed.json
+  → s3://bucket/{session_root}/transcripts/trimmed.json
+```
+
+Rules:
+
+- `from` is local workdir-relative.
+- `to` is session-root-relative.
+- if `required: true` and the source is missing, archive fails.
+- if `required: false` and the source is missing, archive records a skipped promotion.
+
+### 11.4 Commit Pointer
+
+Write these last:
+
+```text
+current/manifest.json
+current/run_id.txt
+```
+
+`current/run_id.txt` should contain exactly the run ID plus a trailing newline.
+
+Writing `current/run_id.txt` last is the effective S3 commit marker.
+
+### 11.5 Failed Runs
+
+Failed runs should not be uploaded to S3.
+
+Failed workdirs should remain local for diagnostics.
+
+The archive stage should never upload a run that does not satisfy its prerequisite success checks.
+
+## 12. Audio Upload Policy
+
+Audio is assumed already present under:
+
+```text
+{session_root}/audio/
+```
+
+Archive should not re-upload source audio by default.
+
+The archive stage may record audio input provenance in manifest, but should avoid duplicating large FLAC files under `runs/{run_id}/`.
+
+A future option may support uploading local audio into S3, but that is not part of this implementation.
+
+## 13. Promotion Defaults
+
+Default promoted outputs:
+
+```text
+transcripts/trimmed.json
+artifacts/session_recap.md
+```
+
+Always write current pointers:
+
+```text
+current/manifest.json
+current/run_id.txt
+```
+
+Do not promote `session_bounds.json` by default.
+
+Do not promote raw transcripts, logs, tool reports, generated configs, or full intermediate transcript tiers by default. They remain available under `runs/{run_id}/`.
+
+## 14. Testing Strategy
+
+Tests should not require real S3.
+
+Use a fake storage backend for:
+
+- listing audio objects
+- downloading objects
+- uploading objects
+- recording upload order
+- simulating missing objects
+- simulating upload failures
+
+### 14.1 Config Tests
+
+Test:
+
+- valid S3 storage config
+- missing bucket when S3 mode enabled
+- default root prefix
+- invalid archive promotion rules
+- default promotion list
+- audio_s3 prefix validation
+- local audio config still works
+- conflict when both S3 audio and local audio are configured, if that rule is implemented
+
+### 14.2 Path Builder Tests
+
+Test S3 key construction:
+
+```text
+dnd/campaigns/forsaken/sessions/2026-04-19/audio/
+dnd/campaigns/forsaken/sessions/2026-04-19/runs/{run_id}/...
+dnd/campaigns/forsaken/sessions/2026-04-19/current/run_id.txt
+```
+
+Test local paths:
+
+```text
+/var/lib/narratio/work/forsaken/2026-04-19/{run_id}/
+/var/spool/narratio/forsaken/2026-04-19/{run_id}/audio/
+```
+
+### 14.3 Prepare Tests
+
+Test:
+
+- S3 audio prefix with `.flac` objects downloads files
+- no `.flac` objects fails clearly
+- non-FLAC objects are ignored
+- downloaded audio is materialized in workdir audio
+- manifest records S3 provenance
+- local audio mode still works
+- fake storage errors fail the stage clearly
+
+### 14.4 Archive Tests
+
+Test:
+
+- archive refuses to run if prerequisites are missing or failed
+- successful archive uploads run record
+- promotion rules upload configured outputs
+- default promotion list applies
+- optional missing promotion is skipped
+- required missing promotion fails
+- `current/manifest.json` is uploaded near the end
+- `current/run_id.txt` is uploaded last
+- failed runs are not uploaded
+- audio files are not uploaded by default
+- manifest records archive metadata
+- fake storage upload failure fails the stage clearly
+
+### 14.5 CLI/Run-ID Tests
+
+Test:
+
+- `run` creates a run ID
+- supplied `--run-id` is honored
+- `resume` can find or require a run ID according to final CLI policy
+- `run-stage` can find or require a run ID according to final CLI policy
+- multiple local runs are handled deterministically
+
+## 15. Implementation Phases
+
+### Phase 1: Config and Path Model
+
+Implement:
+
+- storage.s3 config
+- spool config
+- archive config
+- promotion rules
+- run ID generator
+- campaign-aware local work/spool path builder
+- S3 session/run key builder
+
+No real S3 calls yet.
+
+Expected commit:
+
+```text
+Add archive storage path configuration
+```
+
+### Phase 2: Storage Backend Interface and S3 Backend
+
+Implement:
+
+- storage backend interface
+- object metadata type
+- fake backend
+- real S3 backend using AWS SDK or existing project dependency policy
+- backend construction from config
+
+No stage behavior yet.
+
+Expected commit:
+
+```text
+Add S3 storage backend abstraction
+```
+
+### Phase 3: Prepare Stage S3 Audio Download
+
+Implement:
+
+- S3 audio source support
+- list/download `.flac` files
+- fail on empty audio prefix
+- materialize audio into workdir
+- manifest S3 provenance
+- preserve local audio mode
+
+Expected commit:
+
+```text
+Download S3 audio during prepare"
+```
+
+### Phase 4: Real Archive Stage Run Upload
+
+Implement:
+
+- archive prerequisites
+- upload successful run workdir to `runs/{run_id}/`
+- manifest archive metadata
+- no promotion yet, or minimal internal scaffolding only
+
+Expected commit:
+
+```text
+Upload successful run records to S3
+```
+
+### Phase 5: Promotion Rules and Current Pointer
+
+Implement:
+
+- default promotion rules
+- configurable promotion rules
+- required/optional behavior
+- top-level promoted uploads
+- `current/manifest.json`
+- `current/run_id.txt` written last
+
+Expected commit:
+
+```text
+Promote current session artifacts to S3
+```
+
+### Phase 6: Documentation and Examples
+
+Update:
+
+- architecture.md
+- README.md
+- examples
+- runbook instructions
+- config samples
+- S3 layout documentation
+
+Expected commit:
+
+```text
+Document S3 archive workflow
+```
+
+### Phase 7: Architectural Review
+
+Review:
+
+- storage code isolation
+- prepare/archive stage boundaries
+- no S3 leakage into unrelated stages
+- no failed-run upload
+- current pointer semantics
+- promotion config
+- tests
+- docs
+
+Expected commit:
+
+```text
+Review S3 archive architecture
+```
+
+## 16. Operational Workflow
+
+Expected production flow:
+
+1. Upload source audio to:
+   ```text
+   s3://{bucket}/dnd/campaigns/{campaign}/sessions/{session_id}/audio/
+   ```
+
+2. Run narratio:
+   ```text
+   narratio run --config pipeline.yml --session sessions/{session_id}/session.yml
+   ```
+
+3. `prepare` downloads audio into spool/workdir.
+
+4. Pipeline runs locally.
+
+5. `archive` uploads the successful run record.
+
+6. `archive` promotes configured current outputs.
+
+7. `archive` writes `current/manifest.json`.
+
+8. `archive` writes `current/run_id.txt` last.
+
+Consumers can then read:
+
+```text
+s3://{bucket}/dnd/campaigns/{campaign}/sessions/{session_id}/current/run_id.txt
+s3://{bucket}/dnd/campaigns/{campaign}/sessions/{session_id}/transcripts/trimmed.json
+s3://{bucket}/dnd/campaigns/{campaign}/sessions/{session_id}/artifacts/session_recap.md
+```
+
+## 17. Security and Privacy
+
+Rules:
+
+- Do not store AWS credentials in config.
+- Use standard AWS credential mechanisms.
+- Do not log full environment variables.
+- Do not store secrets in manifests or generated configs.
+- Treat transcripts and artifacts as potentially sensitive.
+- Do not upload failed runs to S3.
+- Preserve local failed workdirs for diagnostics.
+- Do not re-upload source audio by default.
+- Be careful not to log transcript contents during archive.
+
+## 18. Non-Goals
+
+Do not implement in this feature:
+
+- uploading local audio to S3
+- uploading failed runs to S3
+- remote deletion or cleanup policies
+- S3 object lifecycle configuration
+- remote locking
+- multi-user concurrency control
+- a database-backed run registry
+- a generic artifact publishing framework beyond the configured promotion list
+- checksum-based stale detection, except where checksums are recorded as metadata
+- archive-time redaction of manifests; secrets should not enter manifests in the first place
+
+## 19. Open Follow-Up Ideas
+
+Potential future improvements:
+
+- local retention policy for successful workdirs
+- optional cleanup of spool audio after successful archive
+- optional upload of human-readable transcript exports
+- optional promotion of `session_bounds.json`
+- S3-side run index by date/model/prompt version
+- S3 object metadata for checksums and content types
+- remote run discovery for `resume`
+- support for local-audio-to-S3 ingestion mode
+- optional failed-run diagnostic upload behind an explicit flag
+- checksum-based stale detection and stage invalidation
+- archive verification pass after upload