I recently taught a 4-part class on the history and development of the prayer book for Torah in Motion. The entire class is available on YouTube for those interested: https://www.youtube.com/watch?v=qQTSLjGZ7ew&list=PLGQrWlI7O–4b7CvC_dQtlfWCW0nc44kd&index=3

It’s based on the series of article I wrote for 18Forty last year, which is available here: https://18forty.org/wp-content/uploads/2023/08/Who-Wrote-the-Siddur-Series.pdf