A CRM and an accounting system that didn't talk to each other

The situation

The CRM knew customers one way (full name + address). The accounting package knew them another (debtor number + short trade name). One person kept a weekly Excel of what had been added or changed and entered it manually in both systems.

This worked. Until it didn't. A two-week holiday, and three invoices vanished under wrong debtor numbers. Customers called. The director had to fix it.

What we did

We built a one-way sync from CRM to accounting via APIs. Not both ways, that's twice the complexity for little gain. CRM is source, accounting consumes.

The pipeline runs hourly, checks what changed since the previous run, and applies it. Conflicts (a name that doesn't match, a missing VAT number) flow to a simple review page where one person decides in a couple of minutes. No fully-automatic magic nobody can look into.

What it delivered

After two months:

- The Excel: gone. - Weekly manual sync: 4 hours per week → 0. - Invoice-mismatch error rate: from an estimated 5% to under 0.5%. - One central place where you can see what customer data changed in the last week, useful to sales and finance both.

The manager went on holiday again. Nobody noticed.

What this wasn't

Not a migration to a new all-in-one platform. Not a fully-automatic bidirectional sync that silently resolves conflicts. What it was: a simple pipeline where a human decides when something doesn't match.