Can you guess that? a map with 2^24 items? Probaly some limit exceed error? Indeed, JS will throw this “Uncaught RangeError: Value undefined out of range for undefined options property undefined”

Have you ever type command like 2>&1, 3>&2 out of habit without a deep understanding behind it? If so, this article is for you. it explaind the concept of file descriptor and what 1, 2, 3 mean.

How you would go to design an access control system? In this article, tailscale show us how they approach Role Base Access Control in its original design.

When you scan a QR code on any site that support MFA(Multi Factor Authentication), the bar code contains a secret token. The the 6 digit one time password is the result of a function that take input of original secret token and current time stamp. We’ll learn exact steps which that function do

Mailchimp deploy new code that add a log statement. Then their job queue is backed up and job are no longer run. Nothing changes except that log statement. But it’s just a log so they look for in other places. Turning out, the log statement in root cause. But isn’t that obvious that the log is the cuprit? Why no one though so?

Using a hash function for the wrong purpose, or in a place where it doesn’t provide the expected properties, can lead to security vulnerabilities. Some of these vulnerabilities aren’t obvious or straightforward, either, which only serves to magnify confusion.

Optimistic locking in a strategy that we will allow read, and for write we will assume conflict are unlikely, and if it’s conflict we will lock/error out but we push the decision far down the chain. One of way is to add a column lock_version and when upgrading we attempt to compare the current lock_version if it’s different that means the row is updated elsewhere and we will abort it. Let’s apply that into API design

What makes an index usable by a query, and how can we add the right index in Postgres? we’ll look at the practical aspects of using the CREATE INDEX command, as well as how you can analyze a PostgreSQL query for its operators and data types, so you can choose the best index definition.

How would you go about writing a query builder to generate SQL query use a chain-able method instead of string concat? It’s use Python but the idea is sounded