Why on earth are you planning to use Agile methods for such a small scale project?
Agile methods are designed e.g. to handle the risk of unforeseen absences from ruining your project, and to schedule work tasks in a large team. They work by splitting the work to small chunks, assigning a difficulty to each of them, and then by some kind of magic the developers become homogeneous, and each can to a 5-day task in approximately 5 days. Of course, this works best if all developers are skilled and their expertise is not limited to certain areas of the code.
If somebody picks a 5-day task and finishes it in 2 days, the use of agile means there will be a backlog of tasks, so it is possible to pick some other task.
I would say that none of this is required if there's only 1 person in the team.
I would also go further and say that in 10-day project, the use of Scrum may not be so beneficial. How long would your sprint then be? Presumably 10 days, as you planned. Scrum however has been designed to work in projects that have many subsequent sprints. Otherwise you miss the benefits of the sprint retrospective.
I have a method that you may use in your very small scale single-developer project. It's called
TODO.txt. Use it!
As an entirely another matter, I think there are upper limits to the applicability of Scrum in addition to lower limits. So using Scrum in a 100-developer 10-year project may not be ideal. But this is soon starting to become off-topic on an answer to this small-scale question...