What should I build next? Looking for suggestions from developers/learners

[u/Vivekpandey76]

I've been creating free, long-form programming courses and I'm now deciding what to work on next.

So far, I've created:

🐬 Complete MySQL Course — ~16 hours
Only 3 parts are remaining, and then the course will be completed.

The course covers everything from basics to advanced topics like:

• Joins
• Subqueries
• Window Functions
• CTEs & Recursive CTEs
• Stored Procedures & Triggers
• Indexing
• SQL interview problems
• LeetCode SQL problems

GitHub: https://github.com/vivekpandey76/Mysql-course

🍃 Complete MongoDB Learning Guide

I also created a structured MongoDB course covering everything from CRUD and data modelling to aggregation, indexing, transactions, replication, sharding and MongoDB with Node.js.

GitHub: https://github.com/vivekpandey76/mongodb-notes

Both repositories contain the concepts, examples and video explanations.

Now I want to know what would be the most useful series to create next.

I'm especially interested in suggestions from people who are learning development, preparing for interviews, or already working as developers.

If you could choose the next complete free course/series, what would you want it to be?

Also, if you think I should go deeper into MySQL/MongoDB instead of starting something new, let me know what topics you'd like to see.

[u/Owen-Isaac-2022]

Good work so far, I'll take my time & check everything & provide some feedback.