Mac & Windows build instructions

documentation/developer/building.md

@@ -0,0 +1,50 @@
+Building Smack
+==============
+
+Linux
+-----
+
+Building Smack is as simple as
+
+```
+git clone git@github.com:igniterealtime/Smack.git
+cd Smack
+gradle assemble
+```
+
+Mac
+---
+
+Smack requires a case-sensitive file system in order to build. Unfortunately, the macOS operating system is case-insensitive by default.
+To get around this, you can create a case-sensitive disk image to work from.
+
+1. Launch Disk Utility (Applications > Utilities)
+2. Click the +, or go to Edit > Add APFS Volume
+3. Give it a name, e.g. "Smack"
+4. Change the format to "APFS (Case-sensitive)"
+5. Click Add
+
+It'll auto-mount into /Volumes, e.g. /Volumes/Smack
+
+```bash
+cd /Volumes/Smack
+git clone git@github.com:igniterealtime/Smack.git
+cd Smack
+gradle assemble
+```
+
+Windows
+-------
+
+Smack requires a case-sensitive file system in order to build. Unfortunately, Windows NTFS is case-insensitive by default.
+To get around this, you can set specific folders as case-sensitive (requires Windows 10 v1803 or higher).
+
+In an Administrator console:
+
+```batch
+fsutil.exe file SetCaseSensitiveInfo C:\git\Smack enable
+cd \git\Smack
+git clone git@github.com:igniterealtime/Smack.git
+cd Smack
+gradle assemble
+```