Legacy ERP Integration with Twilio SMS

Overview

A multi-company business group needed to introduce SMS communication into a long-established ERP system without disrupting core operations. The ERP had no native support for modern messaging APIs, yet the business required reliable, two-way SMS across multiple companies within the group. We designed and delivered a Twilio SMS integration using an external worker architecture that extended the ERP safely and at scale.

The Challenge

The client needed to:

• Send automated and ad-hoc SMS messages from a legacy ERP
• Capture and process incoming SMS replies
• Support multiple companies, brands, and sender identities
• Avoid blocking or destabilising ERP processes
• Maintain a full audit trail of outbound and inbound messages
• Direct API calls from the ERP were not feasible due to performance, reliability, and architectural constraints

The Solution

We implemented a decoupled integration architecture using a custom Node.js worker queue.

• ERP publishes outbound SMS jobs to a queue
• Node.js worker service processes messages asynchronously
• Twilio handles message delivery and inbound routing
• Incoming SMS replies delivered via Twilio webhooks
• Webhook payloads parsed and written back into the ERP
• This ensured SMS delivery never blocked ERP workflows and could scale independently
• Asynchronous SMS sending via worker queue
• Two-way SMS support with message correlation
• ERP-safe webhook ingestion for inbound replies
• Multi-company support with separate sender IDs
• Message templates per business
• Centralised logging and delivery status tracking

The Result

• Reliable, high-volume SMS delivery from a legacy ERP
• Full visibility of customer replies inside the ERP
• No performance impact on core ERP operations
• Single integration supporting multiple businesses within the group
• Extensible architecture capable of supporting future channels
• The system modernised customer communication without rewriting or replacing the ERP