10% Build Time Improvement

1. Select DWARF (without dSYM) for Debug Information Format (Debug config only).

2. Remove == true, and replace == false with condition negation, fast and simple for non-optional conditions only.

3. Simplify expressions to help the compiler.

Notes:

1. == operator has a lots of overloads slowing compiler time

2. Xcode Find Navigator: Replace > Regular Expression > (if|guard)(\s+)([\w|\.]+) == false with $1$2!$3

3. Check expressions with long comple time using swift-flags: Build Settings ➔ Swift Compiler - Custom Flags ➔ Other Swift Flags:

-Xfrontend -warn-long-function-bodies=<limit>
-Xfrontend -warn-long-expression-type-checking=<limit>

Start with limit of 500 or 1000 milliseconds and move down to 100.

References:

• Swift equality operator takes long time to type check - Using Swift - Swift Forums

• Build performance analysis for speeding up Xcode builds - SwiftLee