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clasp-developers
clasp
Common Lisp2015–2025
clasp-developers / clasp

clasp

clasp Common Lisp environment

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48Distinct people
95Mentions
1Explicit recommenders
2.8KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

clasp Common Lisp environment

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

The GDB JIT interface implementation is seriously flawed. I love GDB - but this causes me a LOT of grief when debugging clasp (Common Lisp implemented using llvm as the backend…

drmeister used a recommendation phrase. One indexed comment matches. This is a phrase match, not a verdict.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

Mentioned in the same Hacker News threads. That is not proof they are substitutes.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 11:23:53 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year95 dated mentions

Observed mentions: 2015-02-21 13:20:00 UTC to 2025-07-09 22:57:28 UTC.

051015202015-01-01 00:00:00 UTC to 2016-01-01 00:00:00 UTC (exclusive): 11 mentions; 2 submissions, 9 comments20152016-01-01 00:00:00 UTC to 2017-01-01 00:00:00 UTC (exclusive): 8 mentions; 0 submissions, 8 comments2017-01-01 00:00:00 UTC to 2018-01-01 00:00:00 UTC (exclusive): 10 mentions; 0 submissions, 10 comments2018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 9 mentions; 0 submissions, 9 comments2019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 12 mentions; 0 submissions, 12 comments2020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 4 mentions; 0 submissions, 4 comments20202021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 12 mentions; 2 submissions, 10 comments2022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 18 mentions; 8 submissions, 10 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 4 mentions; 1 submissions, 3 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 4 mentions; 0 submissions, 4 comments2025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 3 mentions; 0 submissions, 3 comments2025

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20152015-01-01 00:00:00 UTC2016-01-01 00:00:00 UTC1129
20162016-01-01 00:00:00 UTC2017-01-01 00:00:00 UTC808
20172017-01-01 00:00:00 UTC2018-01-01 00:00:00 UTC10010
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC909
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC12012
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC404
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC12210
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC18810
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC413
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC404
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC303

From the project README

An excerpt from the repository, fetched Nov 13, 2026.

Read the project’s introduction
Clasp — Bringing Common Lisp and C++ Together Clasp is a new Common Lisp implementation that seamlessly interoperates with C++ libraries and programs using LLVM for compilation to native code. This allows Clasp to take advantage of a vast array of preexisting libraries and programs, such as out of the scientific computing ecosystem. Embedding them in a Common Lisp environment allows you to make use of rapid prototyping, incremental development, and other capabilities that make it a powerful language. For more information on using Clasp, see: Clasp Manual clbind Documentation Releases See Releases for current releases of Clasp. For more information please see the Release Notes. Building Clasp At the moment, Clasp is supported on Linux, Mac OS X and FreeBSD. On these systems, you should be able to build it from source and you may be able to install using a package manager. See the Wiki for more information. In case things go wrong, the quickest way to get help is to either file an issue, or to chat with us directly. Building takes a lot of resources. In parallel mode (:parallel-build t in config.sexp) you need more than 8 GB of RAM and it will be 1-2 hours build time. If you do not have 8 GB of RAM you can turn off the parallel build which will then run for a day or so. Make sure to have some paging space ("swapfile") configured. There is also docker image here. Common Lisp Ecosystem Support Clasp supports the following major components: SLIME ASDF Quicklisp CFFI Bordeaux-Threads Unicode Post on the issues or contact us if you're interested in changing that. Contributing to Clasp We very much welcome any kind of contribution to Clasp, even if it is just bug finding and testing. A lot can be done all around the project, if you want to dive into something large. See the Contributing file for the few guidelines we've set up around contributions. Reporting Problems Generally you can report problems in two fashions, either by opening a New Issue or by chatting with us directly. In both cases, though, you should have the following pieces handy in order for us to be able to help you out as quickly and painlessly as possible: Your operating system name and version. The branch that you're using of Clasp. A paste of the build log or failure point that you reached. Patience. IRC Clasp has an IRC channel on Libera called #clasp. If you have questions, problems, suggestions, or generally would like to just hang out with us devs, come and stop by! More on Clasp For more information on Clasp and the discussion around it, see the following sites: Christian Schafmeister's blog Hackernews Reddit Google Tech Talks ELS2016 Lessons Learned Implementing Common Lisp with LLVM Acknowledgments Clasp was supported by: The Defense Threat Reduction Agency (DOD-DTRA) (HDTRA1-09-1-0009) The National Institutes of Health (NIH/NIGMS Grant number: 2R01GM067866-07A2) The National Science Foundation (Grant number: 1300231)
Read the full README on GitHub

What Hacker News says

12 sources
lispm·Jul 6, 2019
> Common Lisp still has some activity CLASP is a relatively new Common Lisp implementation with deep C++/LLVM integration. https://github.com/clasp-developers/clasp Quicklisp adds new libraries every month. http://blog.quicklisp.org LispWorks and Allegro CL are commercially available Lisps since 30+ years, running on various platforms and still supported. The LispWorks 7.1 update from 2017 brought native ARM64 support (Linux, iOS), remote debugging of Android and iOS LispWorks, ...
In SBCL – Past, Present, Future [pdf]
m00natic·Jun 18, 2019
Implementing a "simple virtual machine" for a particular task is greenspunning[1]. Introducing a JIT library is work, complexity, debug and portability issues. LLVM compiles much slower to native code as the Clasp[2] guys notice comparing to SBCL. And in the end, any of these would be at most "competitive" to the simple Common Lisp implementation in speed (which is even portable across the different implementations). [1] https://en.wikipedia.org/wiki/Greenspun%27s_tenth_rule [2] https://github.com/clasp-developers/clasp
In Uniform Structured Syntax, Metaprogramming and Run-Time Compilation
drmeister·Mar 31, 2019
We are traveling down this road. We've implemented Clasp (https://github.com/clasp-developers/clasp.git) - an implementation of Common Lisp that interoperates with C++ and uses llvm as the backend. On top of this, we built Cando (https://github.com/drmeister/cando.git) - a computational chemistry programming environment for designing large molecules. The end of our story hasn't been written yet. Clasp could be used for a lot of other things.
In The Programming Language Conundrum
drmeister·Mar 19, 2019
Lisp without s-expressions is like bathwater without a baby. S-expressions enable homo-iconic macros and make compile-time computing super easy! I spent 35 years programming in C and C-like languages and then developed my own Common Lisp implementation (http://github.com/clasp-developers/clasp.git) - the only Common Lisp that interoperates with C++ and uses llvm as the backend. When I started with lisp I wrestled with the syntax and sweet-expressions and just decided to let it go. Now I've found language love all over again! In a world that runs on Javascript, nobody should be able to complain about a few measly parentheses. Obligatory relevant XKCD comic: https://xkcd.com/297/
In Kilo LISP
drmeister·Mar 6, 2019
It's things like the visitor pattern that led me to implement Clasp - a Common Lisp that interoperates with C++ and uses llvm as the backend (github.com/clasp-developers/clasp.git). Common Lisp has generic functions and multiple dispatch - so it doesn't need the wretched visitor pattern. Try writing a compiler using the visitor pattern - I dare you. :-)
In Grim C++ Tales from the Crypt: The Visitor Pattern (2017)
drmeister·Feb 10, 2019
A growing group of us are implementing Clasp (https://github.com/clasp-developers/clasp) - a new Common Lisp that uses Robert Strandh's Cleavir compiler, interoperates with C++ and uses LLVM as the backend. Clasp is the foundation of Cando - a programming environment for the development of molecular devices (https://www.youtube.com/watch?v=mbdXeRBbgDM&feature=youtu.be). Robert Strandh is an exceptionally clear thinker and a fantastic programmer. I can't count the times that Robert has implemented changes to the Cleavir compiler source code and without him being able to test it (long story) passed it to me and it ran flawlessly in Clasp. I implemented his fast generic function solution within Clasp based on another of his papers (http://metamodular.com/generic-dispatch.pdf). Edit: Basically - if Robert writes it up in a paper - I want to
Read the rest
have the implementation. Once we develop molecular robots - they are going to implement LispOS. :-)
In LispOS: Specification of a Lisp operating system (2013) [pdf]

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