qemu

Install:

sudo apt-get install \
  qemu \
  qemu-utils \
  qemu-system-x86

Compiling from source

Thenf or building qemu, install these:

sudo apt-get install \
  libcap-ng-devel \
  libattr1-dev

Build like:

mkdir -p build
cd build
../configure \
--audio-drv-list="" \
--disable-docs \
--disable-opengl \
--disable-virglrenderer \
--disable-vte \
--disable-gtk \
--disable-sdl \
--disable-spice \
--disable-vnc \
--disable-curses \
--disable-xen \
--disable-smartcard \
--disable-libnfs \
--disable-libusb \
--disable-glusterfs \
--enable-virtfs \
--enable-debug \
--prefix=/opt/qemu \
--target-list=x86_64-softmmu
make -j$(nproc)

cloud-utils

Related to qemu are the cloud-init utilities:

sudo apt-get install \
  cloud-utils