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Integration · Custom
Custom API integration for systems nobody else has a connector for
Every business has at least one system without an off-the-shelf connector: a legacy database, a partner portal, a carrier, a machine on the shop floor, a customer's procurement platform, an internally built application.
Overview
What this integration is for
We build custom integrations against whatever interface exists — REST or SOAP APIs, webhooks, databases, SFTP file drops, EDI — with the same reliability standards as any production integration.
01Data
What data syncs, and in which direction
| Entity | Direction | Notes |
|---|---|---|
| Orders | ⇄ Both | From customer portals, EDI or partner systems. |
| Inventory & prices | ERP → App | Published to partners or internal tools. |
| Shipments | ⇄ Both | Carrier and 3PL status exchange. |
| Production data | App → ERP | Machine counts, downtime and quality results. |
| Master data | ⇄ Both | Per agreed ownership rules. |
02Use cases
Common use cases
01
Legacy system coexistence
Keep an old system running alongside the ERP.
02
Partner EDI
Orders, ASNs and invoices with trading partners.
03
Shop-floor integration
Machine data into production records.
04
Customer-facing APIs
Let customers query stock or place orders.
03 — Architecture
API architecture
We place an integration layer between the ERP and the external system, so neither depends directly on the other's internals. The layer handles transformation, validation, queuing and logging.
The interface determines the pattern: real-time APIs or webhooks where available, scheduled file exchange over SFTP for batch partners, and change-detection queries for databases.
04Reliability
Authentication, errors and retries
01
Authentication
Whatever the target supports — OAuth 2.0, API keys, mutual TLS, HMAC signatures, SSH keys for SFTP — with credentials in a secrets manager and least-privilege access.
02
Error handling
Schema validation on every message, clear error categories (retryable vs permanent), and an exception queue with full payloads for diagnosis.
03
Retry strategy
Exponential backoff with jitter for transient failures, idempotency keys on writes, dead-letter queues and replay tools.
05 — Data mapping
Field mapping essentials
| Custom API | ERP |
|---|---|
| External identifiers | ERP external ID fieldsStored for traceability |
| Partner product codes | Product cross-reference |
| Status codes | ERP statesDocumented mapping table |
| Units of measure | ERP UoMExplicit conversions |
| Dates / time zones | UTC in transit |
06 — Automation
Automation opportunities
- Process inbound partner orders without manual entry
- Publish stock and price feeds to partners on schedule
- Capture machine output into manufacturing orders
- Alert owners on failures with replay links
07 — Security
Security considerations
Encrypted transport, scoped credentials, input validation, rate limiting on exposed endpoints and audit logs for every message.
Related
Where this integration fits
Other integrations
Often connected together
ShopifyOrders, customers, products, stock and fulfilment synchronised between Shopify and your ERP.SalesforceAccounts, opportunities, quotes, orders and invoice status between Salesforce and your ERP.Power BIManagement reporting on ERP data in Power BI with a clean model, refresh and row-level security.TwilioSMS, voice and verification through Twilio, triggered by ERP events.
Insights
Related reading
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FAQ
Frequently asked questions
What if the other system has no API?
We use database access, file exports, email parsing or, as a last resort, controlled automation — with tradeoffs explained.
Do you support EDI?
Yes, directly or via EDI providers, for common document types like orders, ASNs and invoices.
Who maintains custom integrations?
We can, under a support plan, or hand over documented code to your team.
Next step
Connecting a custom system to your ERP?
Tell us what you want to automate. We will design a reliable integration with monitoring built in.