TL;DR
A programmer argued that libraries, not new languages, drive real productivity for most users. The author—a language designer—contends that language features shape what libraries can do, so language design and library ecosystems are tightly linked.
What happened
An essay responds to a common claim: that programming languages are largely interchangeable and that the real gains come from libraries. The author acknowledges that libraries like Ruby on Rails have enabled many non-expert programmers to build complex applications quickly, but pushes back on the idea that language design is irrelevant. He shows that Rails leverages Ruby-specific capabilities — meta-programming, runtime evaluation, first-class functions and dynamic typing — and that reproducing Rails in languages without those features (for example Java or C) is not merely an economic or competence problem but a technical limitation. The piece traces how early languages and C-era libraries were shaped by batch computing and numerical tasks, and contrasts that with modern interactive software needs that favor extensible libraries and frameworks. The author gives a personal example: frustration writing a game library in Java led him to prefer Scheme for its continuation support, and motivated designing a new language to better support the kinds of libraries he wanted to write.
Why it matters
- Library ecosystems, enabled by language features, are a primary driver of productivity for many programmers.
- Language design influences what kinds of libraries are practical and how easy they are to use.
- Attempting to port frameworks across languages can fail when required language primitives are absent.
- Decisions about language features have long-term consequences for extensibility and the style of reusable components.
Key facts
- Many programmers attribute productivity gains primarily to available libraries rather than subtle language features.
- Ruby on Rails is cited as an example of a framework that enabled non-experts to build database-driven websites quickly.
- Frameworks like Rails make extensive use of language capabilities such as meta-programming, runtime evaluation and first-class functions.
- Python has a web framework (Django); as of the essay's writing the author judged there was no Java framework as easy to use as Rails.
- The Tiobe index was referenced to note that Java and C ranked highly in usage while Ruby was ranked eighth.
- C-style libraries tend to be collections of functions because of the language's limited reuse primitives.
- Java libraries commonly require creating many handler or subclass types to emulate features that some languages provide directly.
- Interactive software needs led to the rise of extensible libraries and frameworks, a shift from the batch-oriented library designs of the 1970s.
- The author needed continuations/coroutines to express game-character behavior naturally; Scheme provided those features and made the library easier to write.
- Designing a new language (Stanza) was prompted by difficulty implementing the desired library abstractions in Java.
What to watch next
- Whether mainstream languages adopt features (meta-programming, first-class functions, continuations) that make richer libraries easier to implement — not confirmed in the source
- If a Rails-equivalent framework emerges for Java or C that matches Rails' ease of use — not confirmed in the source
- Whether more language designers focus explicitly on enabling library patterns rather than creating new syntax or paradigms — not confirmed in the source
Quick glossary
- Library: A packaged collection of code (functions, classes, modules) intended for reuse by other programs.
- Framework: A higher-level reusable structure that often inverts control and prescribes an application architecture, making certain patterns easier to implement.
- Meta-programming: Techniques that allow programs to read, generate, or modify other programs or themselves at runtime or compile time.
- First-class function: A function treated as a value that can be passed around, returned, or stored in variables.
- Continuation / Coroutine: Control-flow abstractions that let a program pause and resume computations, useful for expressing sequences and cooperative concurrency.
Reader FAQ
Does the author think libraries are more important than languages?
The author says libraries drive productivity for many users but argues language design matters because it determines what libraries can express.
Why can’t Rails simply be ported to Java?
According to the essay, Rails relies on Ruby features (meta-programming, runtime evaluation, first-class functions, dynamic typing) that Java lacks, making a direct port impractical.
Was the author’s push to design a new language motivated by library needs?
Yes; difficulties writing an easy-to-use game library in Java motivated exploring languages with features (like continuations) that better support desired libraries.
Is there a claim that Java or C programmers are less competent?
No. The essay explicitly rejects competence or economics as the reason frameworks like Rails don’t exist in those languages.
HomePhilosophyDownloadsDocumentationPeopleCommunityNewsReference NAVIGATION "Stop Designing Languages. Write Libraries Instead." "Stop Designing Languages. Write Libraries Instead." Patrick S. Li – May 29, 2016 I had a friend tell me recently that all…
Sources
- Stop Designing Languages. Write Libraries Instead (2016)
- Is it better to have a language with features build into …
- Does a new or emerging programming language really …
- The Importance of Libraries in Coding: Building Smarter, …
Related posts
- Earlier Horizon rollout may expand which Post Office convictions get quashed
- The Eric and Wendy Schmidt Observatory System: Faster, Open, Modular Observatories
- Focus Less on New Languages and More on Building Better Libraries