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Featured/Systems/7 min read

Your Architecture Diagram Is a Lie

PK
Piyush Kumar
Co-founder · BackArch · Aug 31, 2026

It was accurate the day you drew it. Then three people changed the system and none of them updated the picture. That isn't a discipline problem. It's that the diagram is the only artifact in your stack with no consequences attached to being wrong.

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8 articles
SystemsAug 31, 2026
Your Architecture Diagram Is a Lie
It was accurate the day you drew it. Then three people changed the system and none of them updated the picture. That isn't a discipline problem. It's that the diagram is the only artifact in your stack with no consequences attached to being wrong.
PK
Piyush Kumar
7 min
BackendAug 27, 2026
JSONB vs Normalised Tables: The Question Isn't "Which Is Better"
JSONB and typed columns aren't competing strategies. They're tools for different access patterns. The right question isn't which is better, it's how you actually query the data.
PK
Piyush Kumar
6 min
BackendAug 24, 2026
When One Table Serves Two Masters: CQRS at the Database Level
A point lookup and a range scan against the same table have opposite indexing requirements. Building one table to serve both shapes optimises for neither. The fix is splitting the write model from the read model.
PK
Piyush Kumar
6 min
BackendAug 19, 2026
The TimescaleDB Extension RDS Wouldn't Install (And What We Used Instead)
The migration worked perfectly in local Docker. On RDS, it failed with a missing extension error. After removing that line, it failed again. This time trying to drop an index that had never been created.
PK
Piyush Kumar
5 min
BackendAug 17, 2026
RDS SSL and the Connection String Parameter That Changed Names Between Drivers
The application health check was green. Alembic was silently failing. Two drivers, one protocol, two different parameter names for the same setting. And a bug that passes every test until your first production deploy.
PK
Piyush Kumar
5 min
BackendAug 13, 2026
The Timing Attack Hiding in Your Login Endpoint
If your login endpoint takes measurably different amounts of time to respond to "email not found" vs "wrong password," an attacker can enumerate every valid email on your platform without ever seeing an error message.
PK
Piyush Kumar
6 min
DevOps & InfraJun 3, 2026
Your CI and Your Deploy Are Racing. CI Is Losing.
The default on: push trigger fires CI and deploy simultaneously. If your tests take four minutes and your deploy takes two, broken code reaches production before the first test result comes in.
PK
Piyush Kumar
6 min
BackendJun 1, 2026
Structure Your FastAPI Backend by Feature, Not by Layer
The layered structure every FastAPI tutorial teaches looks clean in a screenshot. It falls apart the first time you add soft deletes and have to touch five directories for one logical change.
PK
Piyush Kumar
5 min

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