mpapt screenshots:

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Start mpapt:

Find packages with string "dpkg" in the name:
(mpapt)> q {na #dpkg}

From the packages found select only the ones not having ">" in maintainer name:
(mpapt)> q -b {ma !#'debian\.org>'}

For every package in the buffer print its index, name and maintainer name (tab-completed "buf" string):
(mpapt)> b -p '{buf_id} {na} {ma}'

Use magenta for names printing:
(mpapt)> b -p '{buf_id} *m*{na}*n* {ma}'

Print descriptions:
(mpapt)> b --desc

Remove dpkg-cross from the buffer:
(mpapt)> b --rm dpkg-cross

Print buffer contents:
(mpapt)> b

What's in the user buffer?
(mpapt)> b -u

Save the current buffer there:
(mpapt)> b --save

Package no. 5 information:
(mpapt)> b -i 5

The full version:
(mpapt)> b -I 5

Its dependences:
(mpapt)> b -d 5

And with reversed ones:
(mpapt)> b -D 5

Sum up sizes of packages 2, 5 and 6:
(mpapt)> b -p {size} 2 5 6|awk \'{c+=$1} END{print c}\'

Once again, what do we have in the buffer?
(mpapt)> b

Install packages 2 and 4:
(mpapt)> g -b 2 4

Download sources of package 2 to /tmp/dpkg-iasearch directory (creating it if doesn't exist)
(mpapt)> g -b 2 --src --dir /tmp/dpkg-iasearch --mkdir

List /tmp/dpkg-iasearch directory contents ("ls" is not a mpapt command so will be executed as a shell one)
(mpapt)> ls /tmp/dpkg-iasearch

Remove packages found by deborphan:
(mpapt)> rm `deborphan`

Is the logging working?
(mpapt)> tail /var/log/mpapt.log

Find packages with our bash path:
(mpapt)> q {files `which bash`}

Add to the buffer ones with zsh:
(mpapt)> q --add {files `which zsh`}

Create alias "nq" for searching for packages with name passed as its first parameter:
(mpapt)> alias nq 'query {name $1}'

Print aliases:
(mpapt)> alias

Use new alias:
(mpapt)> nq @libapt.*

Which packages can be upgraded?:
(mpapt)> q {upg}

Upgrade number 3 and the four last ones:
(mpapt)> upg -b --no-version 2 `seq 14 17`

Reload apt cache data and print remaining upgradable ones:
(mpapt)> rel; q {upg}

Quit mpapt with ^d: