diff --git a/books/free-programming-books-langs.md b/books/free-programming-books-langs.md
index 8d58aa9db..d181cbcd5 100644
--- a/books/free-programming-books-langs.md
+++ b/books/free-programming-books-langs.md
@@ -2044,6 +2044,7 @@ Books on general-purpose programming that don't focus on a specific language are
 * [Scipy Lecture Notes](http://scipy-lectures.github.io)
 * [SICP in Python](http://www-inst.eecs.berkeley.edu/~cs61a/sp12/book/) (3.2)
 * [Slither into Python: An introduction to Python for beginners](https://web.archive.org/web/20210411065902/https://www.slitherintopython.com/) (3.7) *(:card_file_box: archived)*
+* [Software Design by Example: A Tool-Based Introduction with Python](https://third-bit.com/sdxpy/) - Greg Wilson (HTML)
 * [Supporting Python 3: An In-Depth Guide](http://python3porting.com) (2.6 - 2.x & 3.1 - 3.x)
 * [Test-Driven Web Development with Python: Obey the Testing Goat! using Django, Selenium and JavaScript](http://www.obeythetestinggoat.com/pages/book.html) - Harry J.W. Percival (HTML) *(3.3 - 3.x)*
 * [Text Processing in Python](http://gnosis.cx/TPiP/) - David Mertz (2.3 - 2.x)