diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a3954fd
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,23 @@
+# Ignore everything; except .gitignore
+/**
+!/.gitignore
+
+# Allow src folder, block everything except .py/.txt
+!/src/
+/src/**
+!/src/*.py
+!/src/*.txt
+!/src/*.plaintext
+!/src/*.ciphertext
+
+# Allow src subfolder, block everything except .py/.txt
+!/src/*/
+/src/*/**
+!/src/*/*.py
+!/src/*/*.txt
+
+# Allow doc folder, block everything except .tex/.pdf
+!/doc/
+/doc/**
+!/doc/*.tex
+!/doc/*.pdf
\ No newline at end of file