Use strings.Builder to efficiently concatenate strings by writing to a buffer and converting to a string once at the end.
Use strings.Builder instead of the + operator to avoid creating new string objects on every concatenation. Initialize a strings.Builder, call WriteString or Write to add content, and convert to a string with String() when finished.
import "strings"
var sb strings.Builder
sb.WriteString("Hello, ")
sb.WriteString("World!")
result := sb.String()
Think of strings.Builder as a reusable notepad instead of writing on sticky notes. When you use the + operator, Go creates a new string (a new sticky note) every time you add text, which wastes memory and slows things down. strings.Builder lets you write everything into one buffer first, then creates the final string only once at the end.