On a current project I am working on (a webapp with 6 other developlers) we have a small design doc with core features of the app and transformed everything into small tickets.
We are working in a agile way, but not with scrum, because even we are so many people, scrum would not fit for us.
So, our tools are pretty simple.
And thats actually it :)
We love slack, with all its integrations. So we have a gitlab and trello integration. So even people don't look in the trello board they see whats going on in slack. The same with git pushes.
For our git setup, we are running a git feature workflow, so every ticket (except small 1 liner fixes) are a seperate feature branch. After finishing someone test (tests are must have. no tests = no merge) it and merge it into the develop.
Awesome tools there, Jakub! Yeah! Gotta agree with you on Slack! One question though:
On Trello, do you use the checklists feature extensively within each card to breakdown granular details of your tickets?