[OpenWrt Wiki] Welcome to the OpenWrt Project
https://openwrt.org04.09.2021 · Welcome to the OpenWrt Project The OpenWrt Project is a Linux operating system targeting embedded devices. Instead of trying to create a single, static firmware, OpenWrt provides a fully writable filesystem with package management. This frees you from the application selection and configuration provided by the vendor and allows you to customize the …
[OpenWrt Wiki] Filesystems
https://openwrt.org/docs/techref/filesystemsImplementation in OpenWrt. The flash.layout article documents how OpenWrt uses both SquashFS and JFFS2 filesystems combined into one filesystem by overlayfs. The kernel is also stored separately from these partitions in raw flash. When the kernel is built, it is also compressed with LZMA and gzip, as documented in imagebuilder .