The HFS+ file system used by Apple Computer for their Mac OS is supported by the Linux kernel. Apple provides mkfs and fsck for HFS+ with the Unix core of their operating system, Darwin.

ProjectCenter is an integrated development environment (IDE) for GNUstep systems. It is a clone of the ProjectBuilder application for NextStep, which became popular for its ease of use and speed of development.

AVRDUDE is an open source utility to download/upload/manipulate the ROM and EEPROM contents of AVR microcontrollers using the in-system programming technique (ISP).

Rclone is a program to sync files and directories between the local file system and a variety of commercial cloud storage providers:

Bison is a general-purpose parser generator that converts a grammar description for an LALR(1) context-free grammar into a C program to parse that grammar. Once you are proficient with Bison, you may use it to develop a wide range of language parsers, from those used in simple desk calculators to complex programming languages.