diff --git a/registry/capabilities/capability.railiance.platform-services.md b/registry/capabilities/capability.railiance.platform-services.md
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+---
+id: capability.railiance.platform-services
+name: Railiance Platform Services
+summary: 'S3 Platform Services layer of the Railiance OAS Stack — shared cluster services: PostgreSQL
+  HA, Valkey cache, secret management, identity integration, and object storage.'
+owner: railiance-platform
+status: draft
+domain: financials
+tags:
+- railiance
+- platform
+- secrets
+- postgres
+maturity:
+  discovery:
+    current: D3
+    target: D4
+    confidence: medium
+    rationale: SCOPE.md places this repo precisely at S3 in the Railiance OAS Stack, scoped to shared
+      cluster services (PostgreSQL HA, Valkey, secrets, identity integration, object storage).
+  availability:
+    current: A2
+    target: A3
+    confidence: medium
+    rationale: No top-level package manifest, but ships real scripts/ (OpenBao/Vault apply/verify, credential-change
+      Python tooling) and tools/; has `.forgejo/` CI already in place.
+external_evidence:
+  completeness:
+    level: C1
+    confidence: low
+    basis: scope_vs_intent_and_consumer_expectations
+    satisfied_expectations:
+    - OpenBao/Vault secret-management apply/verify scripting
+    - credential-change tooling
+    broken_expectations: []
+    out_of_scope_expectations: []
+  reliability:
+    level: R0
+    confidence: low
+    basis: consumer_quality_signals
+    known_reliability_risks:
+    - no top-level packaging; scripts/tools have no unified install path
+discovery:
+  intent: Own the shared platform services layer (Postgres HA, Valkey, secrets, identity integration,
+    object storage) that application and enablement layers depend on, without owning the underlying host/cluster
+    substrate.
+  includes:
+  - PostgreSQL HA and Valkey cache service management
+  - secret management (OpenBao/Vault) apply/verify tooling
+  - identity integration and object storage
+  excludes:
+  - host/cluster substrate provisioning (see railiance-infra, railiance-cluster)
+  - application workload deployment (see railiance-apps)
+  assumptions: []
+  use_cases: []
+  research_memos: []
+availability:
+  current_level: A2
+  target_level: A3
+  current_artifacts:
+  - scripts/ (OpenBao/Vault, credential-change tooling)
+  - tools/
+  target_artifacts: []
+  consumption_modes:
+  - cli (shell/python scripts)
+relations:
+  depends_on: []
+  supports: []
+  related_to: []
+evidence:
+  documentation:
+  - SCOPE.md
+  tests:
+  - tests/
+  consumer_feedback: []
+  bug_reports: []
+  incidents: []
+consumer_guidance:
+  recommended_for:
+  - Railiance operators managing shared platform services (Postgres, Valkey, secrets, identity, storage)
+  not_recommended_for:
+  - needs at the host/cluster substrate layer (see railiance-infra/-cluster) or application layer (see
+    railiance-apps)
+  known_limitations:
+  - no unified top-level packaging across scripts/tools
+promotion_history: []
+---
+
+# Railiance Platform Services
+
+## Overview
+
+`railiance-platform` is the S3 Platform Services layer of the Railiance OAS Stack: shared cluster services including PostgreSQL HA, Valkey cache, OpenBao/Vault secret management, identity integration, and object storage, consumed by application and enablement layers above it.
+
+## Assessment notes
+
+### Discovery
+
+SCOPE.md places this repo precisely at S3 in the Railiance OAS Stack, scoped to shared cluster services (PostgreSQL HA, Valkey, secrets, identity integration, object storage).
+
+### Availability
+
+No top-level package manifest, but ships real scripts/ (OpenBao/Vault apply/verify, credential-change Python tooling) and tools/; has `.forgejo/` CI already in place.
+
+### Completeness
+
+First-pass honest assessment from the REUSE-WP-0017 coverage campaign
+(reuse-surface). No external consumer feedback exists yet; levels reflect
+scope-vs-intent documentation quality, not internal code quality.
+
+### Reliability
+
+No production consumer telemetry exists yet; reliability level is
+intentionally conservative pending REUSE-WP-0019 reuse-telemetry evidence.
+
+## Promotion checklist
+
+- [x] ID follows `capability.<domain>.<name>` pattern
+- [x] Maturity enums match `specs/CapabilityMaturityStandard.md`
+- [x] `external_evidence` is populated separately from `maturity`
+- [ ] Relations reference valid capability IDs (none yet)
+- [x] Index entry added in `registry/indexes/capabilities.yaml`
diff --git a/registry/indexes/capabilities.yaml b/registry/indexes/capabilities.yaml
index f944e47..3c28091 100644
--- a/registry/indexes/capabilities.yaml
+++ b/registry/indexes/capabilities.yaml
@@ -1,4 +1,20 @@
 version: 1
-updated: '2026-06-16'
+updated: '2026-07-06'
 domain: helix_forge
-capabilities: []
+capabilities:
+- id: capability.railiance.platform-services
+  name: Railiance Platform Services
+  summary: 'S3 Platform Services layer of the Railiance OAS Stack — shared cluster services: PostgreSQL
+    HA, Valkey cache, secret management, identity integration, and object storage.'
+  vector: D3 / A2 / C1 / R0
+  domain: financials
+  status: draft
+  owner: railiance-platform
+  path: registry/capabilities/capability.railiance.platform-services.md
+  tags:
+  - railiance
+  - platform
+  - secrets
+  - postgres
+  consumption_modes:
+  - cli (shell/python scripts)