Who is CORS? 🤨

CORS

You show up as a sentence
in red.

Not a crash.
Not a stack trace.

Just refusal.

The frontend reaches out—
localhost:3000
calling across the small ocean
to localhost:5000.

The browser stops it.

Not today.

We assume betrayal.
Paste middleware like duct tape.
Refresh.

Sometimes the door opens.

Sometimes you return
with more conditions—
origins, headers, credentials,
preflight questions
asked before anything real can happen.

Early on
you feel petty.

Two machines
one laptop
same developer
same coffee.

Still—no.

Years later
we see the pattern.

The web is a city of locked doors.
You are the quiet rule
that says

ask first.