LIXA, LIbre XA, is a free and open source XA transaction manager
...LIXA implements even XTA: XA Transaction API, an innovative API that implements XA transactional context passing among different applications.
LIXA is a Transaction Manager but it's not a Transaction Monitor: this is the distinguishing feature of the project. LIXA technology enables every application container, like a web server or a shell, to become a two phase commit application server. The client/server architecture of LIXA allows many application containers to share a single LIXA (state) server: this is ideal when horizontal scalability is a must and many identical application containers must refer to a single transactional environment.
...
MEDDAC is the seeding point for designing a new approach to Operating System design itself. It is an Open Source project with roots in mainframe design and development the author began in 1979. Monitor Editor Disassembler Decompiler Assembler Compiler