SoftBase Systems, Inc (1994 - 2013)
Cross-Platform Checkpoint-Restart API
I was given the published API of a mainframe checkpoint/restart tool, and told to implement it in C with an emphasis on portability to different platforms. The software was beta-tested by a company who was porting a COBOL application which used the mainframe tool, and expected the new portable version to be a complete clone of the mainframe interface, down to bugs and quirks. Many undocumented and imprecise aspects of the mainframe implementation were brought to light and introduced for compatibility into the portable version.
During its active lifecycle, this code was ported to Windows, OS/2, HP-UX, AIX, Solaris, and Linux; has worked with both DB2 and Oracle databases; and could be called from many third-generation languages such as C and MicroFocus COBOL. Over the years, this code base has undergone much change and improvement, including the addition of the online monitor, an XML-based configuration file, and support for 64-bit computers.
Finally, though, the checkpoint/restart paradigm died out in software development, as development strategies switched to object-relational mapping tools. The checkpoint/restart product was retired.