In his 1984 MSc thesis[1] and prior work he investigated and formalized the CERES compiler generator (with Neil D. Jones) and showed that (1) a compiler generator is itself a compiler from language definitions to compilers; and (2) under suitable assumptions there exists a language definition that, when applied to itself, generates a compiler generator. This has close connections to self-application in partial evaluation.
In his PhD thesis he developed and proved correct the first sound type system for ML-style polymorphic references, an important open problem at the time. Moreover, he formalized a variant of the module system of the Standard ML programming language.
Mads Tofte is a co-author of the Definition[2] of Standard ML and the associated Commentary, probably the most precise description developed for any realistic programming language. He co-developed the ML Kit, an implementation of Standard ML whose structure closely follows the Definition.
In the late nineties, he co-developed (with Fritz Henglein and others) a type system and a sophisticated tool called AnnoDomini for mitigation of
the Year 2000 problem in COBOL software. The tool analyses legacy programs to discover all data fields that are used as dates. This work was presented in a POPL 1999 invited keynote.[4]
In April 1999, he was appointed the first managing director of the IT University of Copenhagen. He oversaw the creation of the university from scratch, the hiring of faculty/staff, recruitment of students and the design of the study programs. The first students started 5 months later in September 1999. Since 2003 he has been vice chancellor of the IT University of Copenhagen.
In April 2018, it was announced that he would leave The IT University of Copenhagen at the end of the year. In January 2019, he announced that he would sail off from Denmark, to be with his daughter, as a consequence of Denmark's immigration laws, which prevented her from entering the country.[5]
