PACKET FABLE

Small systems.
Clear stories.

Visual stories about the mechanisms behind software, AI and startup decisions. One useful idea. A clear diagram. Something you can try.

Try the free retry lab →Follow on YouTube

The expensive retry

A missing reply does not tell you whether an operation finished. See why a stable ID and server-side replay can prevent duplicate work.

Run the experiment · Technical reference

The discount trap

In this illustrative example, a 20% price cut reduces contribution from $30 to $10 per sale. Variable cost stays constant; fixed costs and tax come out later.

Don't just watch the failure.

Make a simulated response disappear, retry the operation, then compare the results. No real payments or orders. The optional local SQLite example includes checks for duplicate requests, conflicts and rollback.

Open the experiment

Download the Python example · Behaviour checks · Read the six-page sample guide

The code is an educational local demo. External side effects, distributed storage, authentication and a production payment system need additional design.