What skills do self-taught programmers commonly lack? What should a self-taught programmer study to get up to speed with his/her formally-educated peers?

Self-taught programmers are amazing! They bring a ton of passion and dedication to the table. However, there can be some gaps compared to formally-educated programmers due to the structured learning environment. Here's what some of those gaps might be, and how to address them:

**Foundational knowledge:**

* **Data Structures & Algorithms:** These are the building blocks of efficient code. Self-taught programmers might focus on a specific language and miss out on broader concepts. Consider resources like textbooks or online courses on these topics. 

* **Computer Science Fundamentals:**  Concepts like Big O notation, discrete math, and object-oriented programming (OOP) fundamentals are often covered in CS degrees. Brushing up on these areas will strengthen your coding foundation.

**Soft Skills:**

* **Collaboration & Communication:**  Working with others is a big part of the job. Look for opportunities to contribute to open-source projects or online communities to develop these skills.

**Here are some ways to bridge the gap:**

* **Follow a Curriculum:**  Many universities have their CS curriculum online. Use it as a guide to identify areas you might want to explore.

* **Online Resources:**  There are fantastic online courses, tutorials, and communities dedicated to CS fundamentals.

* **Find a Mentor:**  Connect with experienced programmers who can offer guidance and answer your questions.

Remember, being self-taught is a strength!  You've likely developed strong problem-solving skills and a passion for learning. By focusing on these areas, you'll be well on your way to being on par with formally-educated programmers.