AI Summary
5 min readAnders Hejlsberg shares his 40+ years designing programming languages and tools, from Turbo Pascal to C# and TypeScript. He describes starting on 1970s hardware, the role of integrated IDEs in developer productivity, pivotal shifts like the Sun-Microsoft Java lawsuit, and how open-sourcing TypeScript transformed its adoption. The discussion covers compiler mechanics, language design processes, and AI's emerging role in coding.
Origins in Turbo Pascal and Delphi
Hejlsberg began programming in mid-1970s Denmark on an HP 2100 minicomputer with 32K ferrite core memory, writing games in assembly and quirky FORTRAN due to no recursion support. At university, he built an early Pascal compiler fitting into 12K ROM for 8-bit micros like Nascom, replacing slow Microsoft BASIC.
This evolved into Turbo Pascal (1983), a full Pascal implementation for CP/M-80 via a Borland joint venture. It succeeded due to speed (10x faster compilation), small size, interactivity rivaling BASIC, low cost ($49.95 vs. $500 competitors), and an integrated IDE handling edit-compile-run-debug cycles. No separate disks or editors needed; features like halting at error addresses enabled crude debugging.
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What you'll learn
- 1 (02:01) **Anders' Early Programming Days** - High school access to HP 2100 sparks interest in hardware and coding games like Lunar Lander
- 2 (04:43) **First Compiler on 8-bit Micros** - Builds Pascal subset compiler fitting 12K ROM for NASCOM Z80 kit
- 3 (06:50) **Turbo Pascal Creation and IDE Focus** - 1983 joint venture with Borland ships fast, cheap compiler+IDE
- 4 (09:04) **Turbo Pascal's Popularity Factors** - 10x better, 1/10th price vs competitors; minimal piracy
- 5 (11:25) **Delphi Evolution from Turbo Pascal** - GUI shift targets Visual Basic + client-server with compiled RAD
- 6 (14:00) **Joining Microsoft and J++ Era** - Mid-90s Java hype/applets; builds interactive Visual J++ tools
- 7 (16:13) **Sun-Microsoft Lawsuit Births C#** - Lawsuit kills J++; seeks VB ease + C++ power with GC/exceptions
+ Full timestamped outline available in the app
Show Notes
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Anders Hejlsberg is a living legend and one of the most influential programming language designers of all time. He created Turbo Pascal, Delphi, C#, and also TypeScript. As well as that, he spent nearly a decade at the pioneering dev tools company, Borland, and is now in his 30th year of working at Microsoft, where he’s a Technical Fellow.
In this episode, we discuss what it takes to build programming languages that developers love to use, and trace his career from writing his first compiler to creating Turbo Pascal and Delphi, and helping to pioneer modern software development through C# and TypeScript.
Anders details how C# was designed by a small group of experienced language designers who met a few hours each week, and he explains why tooling was just as important as the language for TypeScript’s success, and what he has learned from building languages which stay relevant for decades.
We also look into how Anders uses AI today, which language features suit AI-assisted development, and what he thinks is changing in the craft of software engineering as developers move further away from writing code line by line.
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Timestamps
(00:00) Intro
(02:48) How Anders got into programming
(05:40) Building his first compiler
(07:44) Turbo Pascal
(12:25) Delphi
(14:53) Joining Microsoft
(19:41) Building C#
(29:11) Async/await
(34:01) The rise of JavaScript
(37:52) Building TypeScript
(42:58) How the TypeScript compiler works
(48:30) JavaScript’s strengths and weaknesses
(52:18) How Anders uses AI
(56:03) What language features work well with AI
(1:02:49) How software craftsmanship is changing
(1:07:49) Performance and efficiency
(1:09:29) Anders’ tool stack
(1:11:30) A 30-year career at Microsoft
(1:13:40) Book recommendation
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The Pragmatic Engineer deepdives relevant for this episode:
• Microsoft’s developer tools roots
• 50 Years of Microsoft and developer tools with Scott Guthrie