Added build instructions and stuff

1 files changed, 40 insertions, 1 deletions

diff --git a/README.md b/README.md
index 1669474..76ec084 100644
--- a/README.md
+++ b/README.md
@@ -6,4 +6,43 @@ A calculator to help with invoicing for Norwegian film crew members.
 At first the intention was to make a simple Python script that does what I needed it to do.
 However, it turns out that I don't like python that much anymore, so here we go with making it in C++.
 
-And no warranty or guarantees. This software does not give financial advice.
+It's basically in a usable state now, the first proper alpha release is coming up.
+
+Currently, the only ruleset it follows is the one for advertisement and short-term work.
+Others may be added in the future.
+
+## Building from source
+
+### 🐧 Linux and (probably) MacOS 🍎
+
+You'll need `gcc` and `make`.
+
+```
+git clone https://github.com/SanJacobs/satscalc
+cd satscalc
+make
+```
+
+And if you want to install it, do:
+
+```
+sudo make install
+```
+
+### 🪟 Windows / cross-compilation
+
+You'll need `zig` (Tested with 0.9.1) and `make`.
+
+Using zig because MinGW/GCC can't supply .pdb files needed for debugging with RemedyBG, and clang on Windows is a pain. MSVC is even more of a pain.
+
+```
+git clone https://github.com/SanJacobs/satscalc
+cd satscalc
+make windows
+```
+Or `make windows32` if you need a 32-bit binary.
+
+## Disclaimer
+
+This is free software with ABSOLUTELY NO WARRENTY.\
+This software does NOT give financial advice.