diff --git a/README.md b/README.md
index 1943d3f..93d7082 100644
--- a/README.md
+++ b/README.md
@@ -8,3 +8,7 @@ Code for an STM32-based DSP device.
 * Communicate with a computer program to allow for the reading, writing, and transformation of signals.
 
 See the wiki for pages on each of these goals.
+
+Source code for the device's firmware is in the `source` directory. `gui` contains code for a custom GUI for the device, in C++.
+
+Code for using the device with Mathematica will be added soon.