# VPN Runtime CI Stabilization Changelog

Date: 2026-05-12

This note summarizes local stabilization work for `agents/rap-node-agent/internal/vpnruntime`
and related CI hardening.

## Commit Chain

1. `a3c0998e`  
   Stabilize parallel flow-window test behavior and add initial CI anti-flake checks.

2. `fea5174e`  
   Add `-race` CI check for `vpnruntime`.

3. `4603826b`  
   Add transfer notes with patch/bundle usage instructions.

4. `6fec1d5c`  
   Add targeted CI anti-flake step for the previously flaky test:
   `TestFabricClientPacketIngressParallelFlowWindowDoesNotBlockIndependentChannel`.

## Key Technical Changes

- Test determinism fix in `fabric_transport_test.go`:
  fast send now waits for observed slow-send start boundary, so overlapping
  in-flight behavior is exercised consistently.

- CI workflow hardening in `.github/workflows/build.yml`:
  - backend now runs `go test ./...`
  - new `node-agent` job with:
    - `go test ./...`
    - `go test ./internal/vpnruntime -count=20`
    - `go test ./internal/vpnruntime -run TestFabricClientPacketIngressParallelFlowWindowDoesNotBlockIndependentChannel -count=50 -timeout=60s`
    - `go test -race ./internal/vpnruntime`

## Local Validation Snapshot

- `go test ./internal/vpnruntime -count=100` passed.
- `go test ./internal/vpnruntime -run TestFabricClientPacketIngressParallelFlowWindowDoesNotBlockIndependentChannel -count=50 -timeout=60s` passed.
- `go test -race ./internal/vpnruntime` passed.
- `pwsh -NoProfile -ExecutionPolicy Bypass -File scripts/smoke/run-vpnruntime-ci-guards.ps1 -AntiFlakeCount 20 -TargetedCount 50` passed.
- `go test ./...` passed in:
  - `agents/rap-node-agent`
  - `backend`

## One-Shot Guard Script

- `scripts/smoke/run-vpnruntime-ci-guards.ps1`

Example:

```powershell
pwsh -NoProfile -ExecutionPolicy Bypass -File scripts/smoke/run-vpnruntime-ci-guards.ps1
```

## Transfer/Recovery Artifacts

Local export files are available in ignored path:

- `artifacts/git-patches/0001-Stabilize-vpnruntime-parallel-flow-test-and-add-CI-a.patch`
- `artifacts/git-patches/0002-Add-vpnruntime-race-check-to-CI.patch`
- `artifacts/git-patches/vpnruntime-ci-fixes.bundle`

See:

- `docs/operations/VPNRUNTIME_CI_FIXES_TRANSFER_2026-05-12.md`