I use fish as shell. Here are some tips.

To install:

$ apt install fish
$ chsh -s /usr/bin/fish

Logout and log back in, to start using fish.

To add environment variables: edit ~/.config/fish/config.fish and append:

export M2_HOME="$HOME/local/apache-maven"
export PATH="$PATH:$M2_HOME/bin:$HOME/local"

Useful aliases:

$ alias --save duf="duf -only local" && \
alias --save ff=fzf && \
alias --save ga="git add ." && \
alias --save gcm="git commit -m" && \
alias --save gd="git diff HEAD" && \
alias --save gp="git pull --rebase --autostash" && \
alias --save gpu="git push" && \
alias --save gs="git status" && \
alias --save ls=eza

You need to install a bunch of apps for the above to work:

$ sudo apt install fzf duf eza