A Linked List of Cases in Language Design

Bo Joel Svensson; Benjamin Vedder

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arXiv · 2609.23009

A Linked List of Cases in Language Design

Bo Joel Svensson·Benjamin Vedder

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Abstract

LispBM is a Lisp dialect for microcontrollers and embedded systems. This paper is about the changes made to LispBM resulting from it being integrated into the VESC family of firmware and thus gaining a userbase. As a surprise to Author 1, the new users of LispBM wrote programs larger than ever imagined. This used up all available heap space and we were forced to find a way to evaluate Lisp programs partitioned across RAM and flash memory. This story and a couple more, like the one about the Lisp-image system for fast boots, are the core contribution of this paper. When the first versions of the VESC firmware with a built-in Lisp runtime system were released, there was some grumbling here and there about Lisp and its syntax, as expected. To our delight, most seemed very excited about a scripting language in the firmware. To the engineer and builder users, the choice of syntax seemed to matter less than the potential it opened up for them.

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Bo Joel Svensson, Benjamin Vedder. 2026-09-19. A Linked List of Cases in Language Design. https://arxiv.org/abs/2609.23009

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