I have about three years of professional experience but no computer science degree, and I want to grow into building more complex software. People often say the best way to learn is by building, but I'm not sure how well that applies to data structures and algorithms or system design. I don't expect to learn topics like trees, graph algorithms, scalability, and architecture deeply just by making personal projects. At the same time, I'm worried that studying these subjects first could become a way to procrastinate because I'm nervous about starting a challenging project. Would it be better to study the fundamentals before returning to project work, or should I learn these topics as they become relevant while building?
3 Answers
It helps to distinguish learning DSA concepts from grinding interview exercises. Learn what structures such as hash maps, trees, queues, and graphs are good at, along with their tradeoffs, then use a small number of problems to reinforce that knowledge. Memorizing patterns for dozens of similar exercises is different from understanding the fundamentals, and it shouldn’t delay your projects indefinitely.
You probably don’t need to treat either subject as a prerequisite for building. Start a project, then study the concepts that become relevant when you run into a problem. System design is especially useful when a real project gives you a scaling, reliability, or data-management constraint. Interview-focused DSA is a separate career task, so you can practice it in parallel without waiting to finish months of preparation before writing software.
The two approaches work best together rather than as competing choices. Build something small, and when you notice a limitation or unfamiliar concept, pause for a focused bit of study and then apply it immediately. For example, learn the basics of indexing, caching, queues, or graph traversal when your project gives you a reason to use them. This keeps the learning practical and also prevents studying from becoming an endless substitute for shipping.
Using these concepts in a project is what makes them stick, while structured study helps you discover ideas you would never encounter by chance. A short learning plan alongside regular project work is probably more effective than waiting to feel completely confident first.
A project can expose you to these ideas, but it won’t necessarily teach you their names or show you the alternatives. A to-do app might use a list or map without making you think about complexity or when another structure would be better, so some deliberate study is still valuable.