brew tap servicex-sh/tap
then brew install --no-quarantine servicex-sh/tap/httpx
brew install https://raw.githubusercontent.com/servicex-sh/homebrew-tap/master/Formula/httpx.rb
If you are using macOS Catalina or later you may need to remove the quarantine attribute from the bits before you can use the httpx binaries. To do this, run the following:
$ brew install --no-quarantine servicex-sh/tap/httpx
$ brew reinstall --no-quarantine servicex-sh/tap/httpx
or
$ sudo xattr -r -d com.apple.quarantine $(readlink -f $(brew --prefix httpx))/bin/httpx
brew help
, man brew
or check Homebrew's documentation.