This will take a while to do.

1. Make a new clone of your repo. git clone -bak cd -bak

2. Make a backup of all branches locally in case you fuck up something. git branch -r | grep -v '->' | while read remote; do git branch --track "${remote#origin/}" "$remote"; done git fetch --all git pull --all

   via https://stackoverflow.com/questions/10312521/how-to-fetch-all-git-branches#10312587

3. List all remote branches, oldest first git for-each-ref --sort=committerdate refs/heads/ --format='%(committerdate:short) %(refname:short)'

   via https://stackoverflow.com/a/16961359/1225741

4. Add this to your .(zsh|bash)rc

   git-is-merged() { merge_destination_branch=$1 merge_source_branch=$2

    merge_base=$(git merge-base $merge_destination_branch $merge_source_branch)
    merge_source_current_commit=$(git rev-parse $merge_source_branch)
    if [[ $merge_base == $merge_source_current_commit ]]; then
        echo $merge_source_branch
    fi
   

   }

   git-list-merged() { git for-each-ref --sort=committerdate refs/heads/ --format='%(committerdate:short) %(refname:short)' > /tmp/zsh-git-refs-temp while read line; do git-is-merged HEAD $(echo $line | awk -F" " '{print $2}') #echo $line done < /tmp/zsh-git-refs-temp rm /tmp/zsh-git-refs-temp }

   git-rm-merged() { git-list-merged | egrep --invert-match '(master|sprint)' > /tmp/zsh-git-refs-merged-HEAD while read line; do echo git push origin --delete $line done < /tmp/zsh-git-refs-merged-HEAD rm /tmp/zsh-git-refs-merged-HEAD }

Run git-rm-merged (it's non-destructive, it will echo out what it would do). Adjust the egrep to your liking to exclude branches that you want to leave in.

Remember to source the changed .zshrc with . ~/.zshrc after doing changes.