Merging all commits in repo to one

Today note copied from Stack Overflow (please consider of backuping your repo before this):

git log --oneline

Copy SHA of first commit and next (it's reset your local repo state withouch changing files):

git reset --soft <SHA of first commit>

Check that everything to commit is green:

git status

Commit your changes (--amend fixes last commit), you can change commit message by adding "-m <your new message>":

git commit --amend

Push your changes:

git push --force