### ✅ **Basic Functional Verifications**

1. **Source Trigger Verification**

   * Log a message every time `MockStreamingSource` generates a telemetry.
   * Count how many times `TelemetryAvailable` was raised vs. published.

2. **Destination Receipt Check**

   * Confirm each destination receives telemetry that matches the `ToPayload()` value.
   * Add internal counters per destination to confirm delivery.

3. **Package Identity Tracking**

   * Assign a unique ID to each telemetry object and verify that:

     * It travels all the way to the destination.
     * It is not duplicated or lost.

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### 🔁 **Retry and Backoff Testing**

4. **Destination Retry Logic**

   * Simulate a failure in `MockDestination.Publish()` every Nth call.
   * Verify that retries are scheduled with exponential backoff.

5. **Pending Storage Write/Read**

   * Cause all destinations to fail.
   * Confirm that telemetry is persisted to `TelemetryLiteDBStorageManager`.
   * Manually inspect `PendingTelemetries.Count` after the run.

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### 🕒 **Time & Latency Metrics**

6. **Elapsed Time Per Publish**

   * Log how long it takes from package creation to successful publish.

7. **Latency Bucketing**

   * Track telemetry latency buckets (e.g., `<1s`, `1–5s`, `>5s`) and print histogram.

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### 📦 **Historical and Pending Telemetry**

8. **History Source Verification**

   * Confirm `MockHistorySource.RequestHistory()` is triggered periodically.
   * Verify telemetry from it is published and updated in checkpoints.

9. **Checkpoint Verification**

   * Track when and how often checkpoints are updated.
   * Ensure they persist across runs using `TelemetryLiteDBStorageManager`.

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### 🛠️ **Fault Injection and Resilience**

10. **Out-of-Order Timestamps**

    * Send telemetry with past/future timestamps and check ordering in publish results.

11. **Multiple Concurrent Sources**

    * Add 2–3 `MockStreamingSource` instances and confirm the system handles interleaved input.

12. **Slow Publisher Simulation**

    * Simulate slow or blocking destination publish methods.
    * Confirm queue doesn’t overflow and telemetry is not lost.

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### 🧪 **Extended Diagnostic Reporting**

13. **Final Report Enhancements**

    * Total telemetry generated, published, failed, retried, and persisted.
    * Telemetry per source/destination.
    * Count of `TelemetryAvailable` vs `Publish()`.

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Would you like to start with a few of these now? I can help you implement fault injection, persistence inspection, or anything else you choose.