Tags
#php
#kotlin
#bash
#go
#sql
#rust
#typescript
#html
#java
#python
#files
#utils
#strings
#http
#concurrency
#async
#json
#arrays
#security
#types
#crypto
#database
#dates
#format
Bash
Download with Progress Bar
Show a progress bar for long downloads. wget gives a great built-in bar; curl needs an explicit flag.
@admin
Bash
Tar Archive with Timestamp
Pack up a directory with a date-stamped filename for easy backups. -z for gzip, -j for bzip2, -J for xz (smallest, slowest).
Go
Variadic Functions
`...T` in the last parameter slot accepts zero or more T values. Pass a slice by suffixing with `...` to spread it. Used everywhere from `fmt.Println` to custom builders.
Go
Signal Handling with signal.NotifyContext
Go 1.16+ `signal.NotifyContext` returns a context that's canceled on the listed signals. Cleaner than the legacy `signal.Notify(channel)` dance for graceful shutdown.
Kotlin
require / check / requireNotNull
Three contract-style assertions in the stdlib: `require` for inputs (throws `IllegalArgumentException`), `check` for state (throws `IllegalStateException`), `requireNotNull` returns the value smart-cast.
PHP
Generate Identicon Avatar
Render a deterministic 5x5 symmetric "identicon" placeholder avatar from any seed (usually a user's email or username). No external service — pure GD.
Bash
Sum a Column with awk
Awk's default field splitter is whitespace; pass a single character with -F. Perfect for summing the Nth column of a log file or CSV.
Bash
Get Public IP Address
Several free services return your public IP as plain text. Useful when scripts running behind NAT need to know what address the outside world sees.
Bash
Check Systemd Service Is Running
`systemctl is-active` is the right tool — exit code 0 if running, non-zero otherwise. Combine with restart-on-fail for poor-man's supervision.
Bash
Create User With Sensible Defaults
Provision a new user account with a home directory, default shell, and sudo membership. Idempotent — re-running on an existing user is a no-op.
Kotlin
let — Transform or Null-Safe Scope
`x.let { it.foo }` runs the block with `x` as `it` and returns the block's last expression. Combined with `?.`, it's the canonical "do this only if non-null" pattern.
Rust
windows / chunks — Sliding & Fixed
`windows(n)` yields every overlapping sub-slice of length n; `chunks(n)` yields non-overlapping chunks. Both work on slices for free, no extra crates.
Go
Generic Set Type
A type-safe Set built on `map[T]struct{}` and Go generics. Has Add / Has / Delete / Size — and uses zero bytes per entry for the value side.
Go
database/sql — Open + Query
`database/sql` is driver-agnostic — pick a driver (`pgx/stdlib`, `go-sql-driver/mysql`, `mattn/sqlite3`). Always `defer db.Close()` only on app exit; the pool is meant to be long-lived.
Go
slices package — Modern Helpers
`slices` (Go 1.21+) ships the iteration helpers everyone wrote by hand for years: Contains, Index, Sort, SortFunc, BinarySearch, Clone, Reverse, Equal, Max/Min.
Go
maps package — Modern Helpers
`maps` (Go 1.21+) adds Keys, Values, Equal, Clone, Copy — replaces the slice-of-keys boilerplate you used to write to iterate a map deterministically.
Kotlin
Ktor Server — JSON API with kotlinx.serialization
Install `ContentNegotiation` + `Json` plugin and you get typed (de)serialization for every route. Decode request bodies into data classes; respond with data classes.