As companies grow, they add systems: an ERP, a CRM, an e-commerce site, an HR platform, a field app. Without a plan, these systems connect in ad hoc ways and data gets copied between them by hand. Good IT system architecture keeps growth manageable.
Start with a system landscape
Draw every system, what it does, who owns it and what data it holds. Most companies discover duplicate systems, unknown spreadsheets and fragile manual transfers.
Decide the system of record for each data type
| Data | Typical system of record |
|---|---|
| Customers | CRM or ERP |
| Products and prices | ERP or product information system |
| Employees | HR system |
| Financial transactions | ERP |
| Website content | CMS |
Other systems read from the system of record rather than keeping their own versions.
Choose integration patterns
- Point-to-point APIs: simple for a few connections, but become tangled as systems grow.
- Integration platform or middleware: a central hub manages connections, transformations and monitoring.
- Event-driven integration: systems publish events, such as "order created", and others subscribe. This scales well and reduces tight coupling.
Most growing companies benefit from moving toward an integration platform once they have more than a handful of connected systems.
Centralise identity
Use single sign-on so employees use one account across systems, and access is removed in one place when someone leaves. This improves both security and user experience.
Plan for data and reporting
Feed key data into a central data store or warehouse for reporting and AI, rather than building reports separately in each system.
Design for security and compliance
- Classify data and control where sensitive data flows.
- Encrypt data in transit and at rest.
- Log access to sensitive systems.
- Respect data residency requirements where applicable.
Document and govern
Keep architecture diagrams and integration lists up to date. Review new system requests against the architecture before purchase.
Signs your architecture needs work
- Staff re-type data between systems.
- Reports from different systems disagree.
- Adding a new system takes months of integration work.
- Nobody can explain how data flows.
Our IT system architecture service designs target landscapes and integration plans. Read ERP vs custom software for how core systems fit together.