Things we've built
Two systems that refused to speak.
A booking platform and a finance system, both perfectly happy on their own, both pretending the other didn't exist. Someone re-typed everything twice a day. Here's what we put in the middle.
Try it
Watch one booking make it all the way through.
Then break it. The interesting part isn't the happy path, it's what happens when the other end falls over or the numbers look wrong.
A booking gets made. The invoice used to happen by hand, twice a day, if someone remembered.
Before Someone opened both systems every morning and re-typed 40 bookings into invoices.
You probably need one of these if...
Someone re-types the same thing daily
If a person is the integration, you're paying salary for copy-and-paste and getting typos for free.
Two systems, two versions of the truth
One says paid, one says pending. Nobody knows which to believe, so everyone checks both.
A spreadsheet holds it all together
Exported from one, tidied by hand, imported into the other. It works right up until the person who built it is on holiday.
The last integration failed quietly
It stopped working in March. You found out in June. That's not an integration, that's a rumour.
How we build the middle bit.
Four rules. They've saved us more times than anything clever ever has.
Boring on purpose
No clever framework nobody else can read. A small service that does one job and keeps doing it.
Retries, backs off, keeps its place
Other systems go down. Everything is queued with what it needs, tried again sensibly, and never sent twice.
Speaks up when something's off
Prices that make no sense, missing customers, sudden silence. You hear about it the same minute, not at month end.
You can see what happened
Every message in, every message out, timestamped and searchable. Arguments end quickly.
Got two systems ignoring each other?
Tell us what they are and what someone's re-typing between them. We'll tell you whether it's a week's work or a bad idea.