One of my extensions - Expires Headers - allows an administrator to set future expires HTTP headers for various criteria on a site. Unfortunately, somewhere in the update shuffle of Joomla 3.x - the Joomla API removed the capability to change these headers by setting an impossible to change default (15 minutes). This means I've got a software package that does diddly-squat. It used to bring better SEO - but now it just takes up space (and server resources).
Once I determined where and what was going wrong, I set out to remedy the situation. That journey led me to the discovery that Joomla HTTP header output was far behind the current standard. Upon reviewing the code and planning my approach, I was able to implement a fully backward compatible upgrade to the current class - and happily, it will be included in the next version of Joomla!
I love seeing my name in the credits - and I really love knowing that my work will be running on millions of websites worldwide (once again).