Скачать или смотреть Week 37 | Email Infrastructure: The Outbox Pattern

Recording outside as summer ends! This week I'm overhauling the email infrastructure, moving from a naive one-function-per-email approach to a sophisticated outbox pattern with batch processing and webhook integration. This is one of the bigger architectural changes and touches database, Edge Functions, and external services.

📱 *Shokken App Progress:*
✅ Kermit logging successfully diagnoses issues
✅ Parsing error fixed (fetch after insert)
🔄 Email infrastructure overhaul in progress
🔄 Outbox pattern implementation
🎯 MVP nearly complete after this

🤖 *Blog Post:* https://endian.dev/blog/2025/37/

Chapters
12:06 Week 37 Introduction
12:08 Recording outside, summer ending
12:13 Last week's success with Kermit
12:24 UI problem diagnosis and fix
12:38 Data layer insert/fetch issue explained
13:23 Error handling improvements
13:30 Email sending backend overview
13:56 Problems with naive implementation
14:20 Edge Function setup/teardown costs
14:58 Missing webhook integration issues
15:43 New implementation: Outbox pattern
16:32 Priority outbox for urgent emails
16:58 Webhook setup for event tracking
17:18 Scope of implementation
17:34 MVP completion in sight

Key Topics Covered
Edge Function economics and hidden costs
Outbox pattern architecture
Batch processing for cost reduction
Webhook integration for event tracking
Database schema design for email queuing
Cron job configuration
Error handling and retry strategies
Priority queue implementation
Cost analysis (90% savings)

Technical Highlights
**Problem**: Edge Functions charge for setup/teardown time (66% overhead)
**Solution**: Batch processing reduces 1000 invocations to 20
**Cost Savings**: $810/month at 100K emails/day scale
**Architecture**: Separate priority queues for urgent notifications
**Resilience**: Exponential backoff, automatic retries, suppression lists

Implementation Details
Outbox table with priority and retry logic
Advisory locks for concurrent processing prevention
Row-level locking with "FOR UPDATE SKIP LOCKED"
Webhook signature verification for security
Event tracking and analytics aggregation
Health monitoring and alerting system

Resources
📝 Blog: https://endian.dev
🐙 GitHub: https://github.com/endian-dev
📱 Shokken App: Coming to Google Play & App Store

About Shokken
Shokken is a modern waitlist management app replacing traditional buzzer systems with smart notifications. Built with Kotlin Multiplatform, targeting Android, iOS, Web, and Desktop platforms.

#Programming #EmailInfrastructure #OutboxPattern #EdgeFunctions #Supabase #Webhooks #SystemDesign #CostOptimization #Kotlin #BackendDevelopment #MVP #StartupDevelopment #TechBlog