Nimaruya / personal labBackend / systemsLab issue 001 — 2026
MariaNichiporenko
Backend engineer.
Currently working in fintech.
I like systems with many moving parts.Building them, understanding them,and deciding which complexity is actually necessary.
- Architecture
- Business logic
- Distributed systems
System design / Queues / Databases / Business logic / Trade-offs / New tools / How things work /
01 / Lab directoryRef. NMR/LAB/001
What you’llfind here
Interactive explanations, technical notes, and whatever else seems worth looking into.
02 / ExperimentsStatus: in progress
Experiments
Backend problems that are easier to understand when you can change something and see what happens.
- 01How to charge
someone twiceIdempotency, retries and ambiguous failures. - 02Everything arrived.
In the wrong order.Webhooks, ordering, and the difference between events and state. - 03Things that should
work. Mostly.Small backend behaviors, edge cases, and failure modes that are easier to see than explain.Soon
03 / NotesField note 001 / status: published
Field
notes
Things I learned, noticed, questioned, or needed to write down before I forgot.
- 01Payments, retries and webhooks: where certainty ends
- 02I write less code now. I think that's the point.Some notes on what changed when writing code stopped being the expensive part of software development.Soon
- 03Most bugs live between the boxesWhy individually correct components still produce broken systems — and why boundaries deserve more attention than they get.Soon
Status: in progressLast checked: just now
Everythingisworkingasexpected
* probably