Tomatoware is a development environment for mipsel and ARM embedded routers. It can be used to natively compile userland applications for these devices.
Downloads for the project available at:
https://github.com/lancethepants/tomatoware/releases
http://lancethepants.com/files
Tomatoware can be compiled with different root prefixes. This allows it to co-exist with entware(-ng)/optware(-ng), which reside in /opt. The official project prefix is /mmc.
Edit config.mk to set the desired architecture and prefix and run make.
Debian 8 is used to build this project. An included Dockerfile can be used to create a working enviornment. Otherwise the following packages should be sufficient.
apt-get install automake bc bison build-essential cmake cpio curl flex gettext git libglib2.0-dev libncurses5-dev libtool libxml2-dev locales pkg-config python sudo texinfo unzip vim wget