update readme.

README.md

@@ -1,5 +1,36 @@
 # Furnace
 
-that does it.
+did i say prepare?
 
-thanks for nuking your user base. worst way to break our hearts.
+this is a work-in-progress chip music player (currently) for the .dmf format.
+
+## features
+
+- supports Sega Genesis, Master System and Game Boy (for now, with more systems coming soon)
+- clean-room design (zero reverse-engineered code and zero decompilation; using official DMF specs, guesswork and ABX tests only)
+- bug/quirk implementation for increased playback accuracy
+- accurate emulation cores (Nuked, MAME and SameBoy)
+- open-source. GPLv2.
+
+## dependencies
+
+SDL2. untested on Windows/macOS.
+
+## compilation
+
+your typical CMake project. clone and:
+
+```
+mkdir build
+cd build
+cmake ..
+make
+```
+
+## usage
+
+```
+./furnace <file>
+```
+
+this will play a file (must be in .dmf format).