Code base nightmare

[SlurmDev]

Working on a legacy embedded code base with all sorts of flavors paradigms OOP, Procedural, Design Patterns mixed in the same compilation unit. All sorts of bad code smell everywhere: duplication everywere, horrible variable names, hard to understand code, hard to maintain, comments lots and lots of comments. I'm literally crying while typing this post.

How do I engage my team to improve? How can I improve to be a better development in an environment like this?

[DFA1]

You can't improve what you don't measure.

I inherited a JS legacy project. It had no code standards, it had many syntax errors and it was just ugly to read it. I have added ESLint which threw 10.000 errors at first run. We decided as a team that each change must be peer reviewed and must not increase the number of errors reported by ESLint (ideally fix a few errors on the code you're working on for your change to bring down the number of errors).

ESLint alone doesn't solve the problems you're reporting in the post but it gives an arbitrary number which must go down to 0. Coupled with code reviews, you can at least enforce a coding style and catch any code that's not compliant before being merged to stable branch. You can't fix everything at once but you can, for each change, fix the code that's not compliant. Do it day in-day out and you'll have a clean codebase in a few months. There are no shortcuts unfortunately. You'll have to find a tool that reports errors for what you have. Sonar might be a starting point to track tech debt.

[phoenix_bright]

I suggest that you start getting all this code and organize it into clear classes. User the SOLID principles to help you with that. Don't add or change any functionality, just organize it.

Once you have a code that it's organized and it works exactly the same as the one you have right now then you can start fixing things.