I've been writing code for over 10 years now, and although I've been doing more management lately, at my peak I was able to write 500+ lines of well-performing code a day. Here are the principles that helped me with this:
Don't over-generalize
Don't optimize your code in advance
Name and group everything that happens correctly
Don't mix algorithms and other technologically complex pieces of code with business logic
Don't use any advanced features of any language
It is worth throwing all OOP out of your head
Use as many asserts, logs and other methods to catch unplanned system state as early as possible
Every extra line of code is evil
Every extra line of code is evil:) Wherever possible, you should not use someone else's code that you have not read and understood
I've been writing code for over 10 years now, and although I've been doing more management lately, at my peak I was able to write 500+ lines of well-performing code a day. Here are the principles that helped me with this:
Here I placed just names of my mistakes, but if you are interested here the full version with each point explanations