Many of these binaries are built using the Entware toolchain, and build scripts are hosted at the following github link. Some binaries may also be stripped and compressed using upx.
https://github.com/lancethepants


The rest of the binaries can be reproduced by compiling them using Tomatoware, and building them on the router.
https://github.com/lancethepants/tomatoware


Feel free to email me if you want to repoduce the build process and need help.
lancethepants@gmail.com