An MCP server in front of a business platform
Twenty-six typed tools instead of one query tool, two auth schemes, bounded results, and the authorisation rule that decides whether it is safe at all.
The third verdict — rules that check without deciding
Two verdicts force a system to call missing data a failure. The third one — to be checked — is what separates a decision aid from an automatic rejection.
A foreign key we deliberately did not create
Referencing by code instead of by FK buys real decoupling and costs a guarantee. An incident, its two faults, and why the second one was worse.
Materialising a form as a real PostgreSQL table
JSONB stops paying off eventually. Here is how a user-drawn form becomes a real typed table, versioned outside django_migrations, additively.
A DNS zone you can only write whole
SET_DNS_ZONE replaces everything. That one constraint decides where truth lives, how you delete a record, and why the mail block is published late.
An OCR result that knows which field it filled
Every OCR tutorial ends at image_to_string. Production starts there — attaching the text to a field, storing failures, and a confidence score that is not one.
Sixteen operators, six actions, two implementations
Conditional form logic in the browser is presentation, not validation. Keeping show, enable and require independent — and the half that must exist twice.
A form that does not exist when Django starts
A form builder means the form does not exist at import time. Here is the dispatch, the degradation rule, and the N+1 that a dict literal hides.
Configuring django-tenants properly
Schema per tenant is the easy part. This is the configuration that decides whether your image builds, whether a Postgres blip takes the fleet down, and whether migrations run.
One entrypoint.sh for a laptop, a VPS and a fleet
Waiting for Postgres is the easy line. Extensions before migrations, assets from the image, and one release job instead of four concurrent migrations.