The Scrum framework can usually be adapted to any product or service that can benefit from time-boxed effort and incremental delivery. That doesn't mean it's the best fit for every project, but the original question does not describe anything that can't fit into a Scrum implementatation.
The question, as currently constituted, ...
Scrum is a buzz word among managers, especially those never doing actual coding/analysis/testing. It suits some specific projects, but not all. It is not suitable for many, these dealing with highly technical topics is one of them. Scrum is actually known for accumulating technical debt (is is easy to just shuffle these 'not nice' tasks somewhere down in the ...
Adding a bit to Daniel's excellent answer.
all the work is deeply technical and has no user facing consequences
But you also say:
focused on improving the performance of the product as a whole
I can think of two reasons why you might improve the performance of the product:
To improve the user experience (quicker response times, etc.)
Is Scrum actually suitable for all kinds of projects?
Like with many things in the software industry, Scrum is not a silver bullet. It works nicely for some types of projects, and less so for others. I've often seen the Cynefin Framework mentioned when trying to identify projects types where Scrum might be used, so maybe have a look at it and see under what ...
To your overall question, while Scrum can be applied in most projects, it is not necessarily the best approach for some projects. That said, it is well suited to complex problems that require discovery of the solution and adaptation to new information. Your project sounds like exactly the kind of project Scrum was designed to tackle. However, you raise some ...
When you receive a bug report, it needs to be triaged. The workflows that I use tend to look something like this:
Review the bug report and confirm that it truly is a bug. Some people who report issues may not be aware of the intended behaviors of the system. The issue reported could be acting as designed.
Assuming that the issue is a bug, check the quality ...
If I understood your question correctly, it seems that tasks are not very well defined which is root cause of this issue. While user stories are good to describe a task, one should try to include different mediums to translate and define business need in accurate form for related team members. Project team members has different view points based on their ...
Your current process contains a large set of agile anti-patterns. Some of these process dysfunctions include:
"Testing" divorced from a Definition of Done (DoD).
Lack of test-first development.
Sequential (rather than collaborative) activities.
Treating changes (other than DoD gaps) as rework rather than new work.
While JIRA's ticketing model is ...
How is your 'rejection workflow?'
If you need a workflow to handle rejected user stories, then you have a problem.
Normally, a user story being rejected should be an exception; someone misunderstood something, someone made the wrong assumption, someone failed to communicate... it happens. Nobody's perfect. But when it happens it's something that it's ...