Build Custom Middleware to Connect Your Business Systems

Many businesses start with task-based automation platforms. They're great for simple triggers, like sending a Slack message when a new lead arrives. But they fail when real business logic is needed. A workflow that must check inventory in one system and a customer's credit in another before creating an invoice requires duplicating logic, which doubles task usage and cost.

A regional insurance agency with 6 adjusters tried connecting their claims management system to their accounting software. The platform's webhook listener had a 30-second timeout. If the accounting system's API took 31 seconds to respond during peak hours, the entire workflow would fail silently. This resulted in 15% of invoices being dropped, discovered only at the end of the month.

These platforms are designed for linear, stateless tasks. They cannot manage complex state, handle multi-step transactions with rollbacks, or provide the detailed, structured logging needed to debug production issues. When a process is critical to revenue, you cannot rely on a system that treats every API call as an isolated, billable task with no transactional guarantee.

Syntora would begin by auditing your existing systems and mapping every relevant data field between source and destination. We would use tools like Postman to document each service's authentication method (such as OAuth2 or API Key) and API rate limits. For an integration between a CRM and an ERP, this discovery phase typically involves identifying and mapping 20-30 distinct fields and defining transformation rules, an activity that usually takes 3-4 days.

We would build the core logic as a FastAPI application in Python. Our approach emphasizes creating functions that are idempotent and transactional, ensuring data consistency even if operations are retried. We would use httpx for asynchronous, parallel API calls, enabling simultaneous querying of multiple systems to optimize processing time. All logs would be written as structured JSON using structlog, facilitating instant searchability within platforms like AWS CloudWatch.

The FastAPI application would be deployed as a serverless function on AWS Lambda. This architecture offers automatic scaling and, for typical usage patterns, aims for operational costs under $20 per month for up to 1 million invocations. For any data requiring temporary storage or caching between API calls, we would implement a Supabase Postgres database. This design provides a production-grade service without the overhead of managing dedicated servers.

The delivered system would include built-in health checks and monitoring. We would configure AWS CloudWatch alarms to notify stakeholders of critical events, such as sustained high error rates or unusual latency, sending alerts to a dedicated Slack channel for prompt investigation. As part of our engagement, we would provide a comprehensive runbook detailing how to interpret and respond to these alerts, ensuring your team can effectively manage the system post-delivery.