Anders Hejlsberg
Creator of C# and TypeScript
The Danish engineering legend behind Turbo Pascal, Delphi, C#, and TypeScript. He calls AI “a big regurgitator” — and yet positions TypeScript as the guardrail language of the AI era, uses AI in his own compiler work, and says AI is “doing the work” while humans supervise.
In his words
AI started out as the assistant. Now it’s doing the work, and you’re supervising. It doesn’t need an IDE the way we do. It needs the services.
AI’s ability to write code in a language is proportional to how much of that language it’s seen. It’s a big regurgitator, with some extrapolation.
The goal is to box in AI workflows with just enough determinism that they stay useful without going off the rails.
Biography
Anders Hejlsberg (born 1960 in Copenhagen) has designed landmark developer tools across five decades: Turbo Pascal at Borland in 1983, the Delphi environment, then — after moving to Microsoft in 1996 — the C# language and, from 2012, TypeScript, the typed JavaScript that now dominates web development. A Microsoft Technical Fellow, he remains TypeScript’s lead architect, and in 2025 led the headline-grabbing port of its compiler from TypeScript to Go for a 10x speedup.
The regurgitator and the guardrails
Hejlsberg’s AI commentary mixes deflation with adoption. In a GitHub Blog interview published in November 2025 he described AI bluntly — “a big regurgitator, with some extrapolation” — noting that a model writes a language only as well as the amount of it in the training data, which advantages incumbents like TypeScript and Python and disadvantages new languages. In a January 2026 DevClass interview he repeated the line with more edge: “a big regurgitator of stuff someone has done, with some extrapolation on top.”
Yet his conclusions are the opposite of rejection. He frames TypeScript’s type system as exactly the deterministic guardrail AI-generated code needs, and describes the workflow shift matter-of-factly: the AI now does the work while the human supervises, and tooling should serve the model with “services,” not IDEs. His team tried using AI to translate the half-million-line compiler to Go and found it wanting — “that went not so great … we want a very deterministic outcome here” — but has, in his words, “actually been using AI fairly successfully” to migrate ongoing pull requests to the Go codebase, and he predicts “AI is gonna do a way better job” in areas of the TypeScript language service.
It is the pattern of the pragmatist wing of language creators — closer to Linus Torvalds than to Rich Hickey: puncture the mystique, then quietly wire the technology into the toolchain because it works.
Where they stand in the war
Who backs them up
Sources & further reading
Canonical record: https://battlelines.ai/topic/anders-hejlsberg