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 Small portfolio prototypes for telemetry analytics, monitoring, and detection-oriented signal processing.
 
+Latest milestone: [v0.4.0 — second demo and portfolio integration](https://github.com/stacknil/telemetry-lab/releases/latest). See [release notes](docs/release-v0.4.0.md).
+
 ## Demos
 
 - [telemetry-window-demo](#telemetry-window-demo)
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+# v0.4.0 — second demo and portfolio integration
+
+This is a small portfolio milestone release for `telemetry-lab`.
+
+The repository now presents a two-demo structure:
+
+| Demo | Role |
+| --- | --- |
+| `telemetry-window-demo` | Windowed telemetry analysis with deterministic rules, CSV outputs, and timeline artifacts |
+| `ai-assisted-detection-demo` | Deterministic detection and case grouping with constrained LLM summarization and auditable rejection paths |
+
+## What changed
+
+### Repo structure and front door
+
+- The landing page now presents `telemetry-lab` as a two-demo repository
+- The top-level README includes direct navigation to both demos
+- The public repo story is now easier to scan from the landing page
+
+### New second demo
+
+- Added `ai-assisted-detection-demo`
+- The demo centers on:
+  - deterministic detection
+  - deterministic case grouping
+  - constrained LLM summarization
+  - audit traces and visible rejection paths
+
+### Guardrails and boundaries
+
+- `human_verification` is required
+- No autonomous response actions
+- No final incident verdict
+- No LLM-driven detection or grouping decisions
+- Fail-closed validation remains in place for invalid or disallowed outputs
+
+### Reviewer-facing documentation
+
+- Added a walkthrough for:
+  - accepted summary path
+  - rejected summary path
+  - degraded coverage path
+- Added an explicit lifecycle contract and audit schema version in the design documentation
+
+## Why this milestone matters
+
+This release moves `telemetry-lab` from a single-demo prototype toward a clearer portfolio repository with:
+
+- one telemetry/windowing workflow
+- one case-centric, AI-assisted investigation workflow
+- explicit guardrails around model output and operator review
+
+## Validation
+
+- Full test suite: `43 passed`
+
+## Notes
+
+This is a portfolio milestone release, not a product launch.
+The repository remains intentionally scoped to small, reviewable prototypes.