Integration checkpoint for epic-external-system-integration-configuration-backend-infrastructure
epic-external-system-integration-configuration-backend-infrastructure-integration-task — Integration Task
Integration Purpose
Verify integration with dependent epics: epic-external-system-integration-configuration-foundation, epic-external-system-integration-configuration-core-services
This integration checkpoint ensures proper coordination and compatibility between different epics. It verifies that all interfaces, data flows, and dependencies are correctly implemented before proceeding.
Integrates With Epics
Execution Context
Tier 6 - 158 tasks
Can start after Tier 5 completes
Handles integration between different epics or system components. Requires coordination across multiple development streams.
| Status | pending |
| Type | Integration |
| Estimated | 4h |
| Tier | 6 |
Supabase Edge Functions have cold start latency that can cause the first sync invocation after idle periods to fail or timeout when the external API has a short connection window, leading to missed scheduled syncs that go undetected.
Mitigation & Contingency
Mitigation: Configure Edge Function memory and implement a warm-up ping mechanism before heavy sync invocations. Set generous timeout values on the external API calls. Log all cold-start incidents for monitoring.
Contingency: If cold starts cause consistent sync failures, migrate the sync scheduler to a persistent Supabase cron job that pre-warms the function 30 seconds before the scheduled sync time.
The sync scheduler must execute jobs at predictable times for financial reporting accuracy. Drift in cron execution timing (due to Supabase infrastructure delays) could cause syncs to run at wrong times, leading to missing data in accounting exports or duplicate exports across reporting periods.
Mitigation & Contingency
Mitigation: Implement idempotency keys based on integration ID + scheduled period, so re-runs of a delayed sync cannot create duplicate exports. Log actual execution timestamps vs scheduled timestamps and alert on drift exceeding 5 minutes.
Contingency: If scheduler reliability is insufficient, integrate with a dedicated cron service (e.g., pg_cron on Supabase) for millisecond-precise scheduling, replacing the application-level scheduler.
Aggressive health monitoring ping frequency could trigger rate limiting on external APIs (especially Xledger and Dynamics), causing legitimate export calls to fail after the monitor exhausts the API's request quota.
Mitigation & Contingency
Mitigation: Use lightweight health check endpoints (HEAD requests or vendor-specific ping/status endpoints) rather than data requests. Set health check frequency to once per 15 minutes minimum. Implement exponential backoff after consecutive failures.
Contingency: If rate limiting occurs, disable active health monitoring for the affected integration type and switch to passive health detection (mark unhealthy only when a scheduled sync fails).