Niklaus Wirth

What they built

Swiss computer scientist; designer of a sequence of languages, each deliberately smaller than the one before: Euler, Algol-W, Pascal (1970), Modula-2 (1978), Oberon (1987). With Jürg Gutknecht he designed not just the Oberon language but the Oberon operating system — a complete graphical single-user OS small enough for one person to understand. Professor at ETH Zürich from 1968; Turing Award 1984. Died January 1, 2024, age 89.

In their own words

• "In spite of great leaps forward, hardware is becoming faster more slowly than software is becoming slower." — A Plea for Lean Software, IEEE Computer, February 1995. He credited the line to Martin Reiser; it became Wirth's Law.
• On ALGOL-68's complexity, recounting showing the draft report to someone: "I pulled out my copy of the draft report on ALGOL-68 and showed it to her. She fainted." — The Register obituary, 2024, recounting a Wirth anecdote about why he walked away from the ALGOL-68 committee.
• "I always saw myself as an engineer." — ETH Zürich interview, 2021. Framed his work as craft, not pure science.
• On new languages becoming bloated by committee demand: they "turned out to be overly complex due to the demands of practitioners," with some collapsing under their complexity and others becoming "too restrictive for use in practice because of their academic straight-jackets." — widely cited from his ETH writing.
• On his own naming, once joking that Europeans called him by reference (Nik-laus Virt) and Americans by value (Nickel's Worth) — a Pascal gag about parameter passing, recounted in multiple obituaries.

Principles as they articulated them

• Make it smaller. Every successor language (Pascal → Modula-2 → Oberon) is a subtraction exercise, not a feature addition.
• Committees corrupt languages. After his ALGOL-68 experience on IFIP WG 2.1, he published later languages as personal work, refusing the standards-committee path.
• A single person should be able to read and understand a full operating system. Oberon was proof-by-construction.
• Simplicity is the form engineering takes when it respects the user; complexity is the form it takes when it respects vendors.

What surprised me in research

• Wirth retired in 1999 but came back in 2013 to publish an updated Project Oberon — code, book, hardware description — with the goal of having a compact, fully understandable system available for students a generation later. He kept working on it into his 80s.
• He spent two sabbaticals at Xerox PARC (1976-77, 1984-85) and explicitly saw Mesa/Cedar as too complex; Modula-2 and Oberon are in part reactions against PARC's own maximalism, not extensions of it.
• He was not only a language designer: the Lilith workstation (1980) was a full bespoke computer he designed because no commercially available machine was fit for Modula-2.
• A Plea for Lean Software (1995) is sharper than it's usually remembered — it names specific culprits (Windows, feature-driven product management) and argues that fat software is a moral failure of the profession, not merely an aesthetic one.

Recent or later work

Project Oberon 2013 edition (with Gutknecht) — revised book, revised RISC processor design implementable on an FPGA, complete source of the OS. The 2021 ETH video interviews are his late-career self-summary. He gave occasional talks and wrote short pieces until his death on January 1, 2024.

Sources

• https://www.theregister.com/2024/01/04/niklaus_wirth_obituary/ — RIP: Software design pioneer Niklaus Wirth — theregister.com
• https://inf.ethz.ch/news-and-events/spotlights/infk-news-channel/2021/11/niklaus-wirth-video-interview.html — "I always saw myself as an engineer" — inf.ethz.ch
• https://amturing.acm.org/pdf/WirthTuringTranscript.pdf — Turing Award Oral History (Wirth) — amturing.acm.org
• https://people.inf.ethz.ch/wirth/ — Wirth personal page, Project Oberon — inf.ethz.ch
• https://bertrandmeyer.com/2024/01/16/niklaus-wirth-importance-simple/ — Niklaus Wirth and the Importance of Being Simple — bertrandmeyer.com