Backend guides
Connect how clients talk to your server, how you model data, and how you keep services reliable and safe.
What is a message queue and why do backends use background workers?
Decouple request time from work time: produce jobs, consumers process at their pace, with retries and DLQ.
asyncqueuesreliability
What is a webhook and how do you verify an HMAC signature?
The provider POSTs to your URL; you prove the body came from them using a shared secret and a hash in a header.
securityhttpwebhooks
What is a database connection pool in a web server or API?
Reuse TCP connections to Postgres or MySQL instead of handshaking for every request.
sqlperformancepostgres
What is the difference between offset and cursor pagination in APIs?
Offset/LIMIT is simple but shifty under concurrent inserts; cursors are stable for large feeds.
apisqlperformance