CodeArchaeology

SymbEL - pronounced "symbol", and known to almost everyone who used it simply as "SE" - is Richard Pettit's interpreted, C-like language for reading performance data out of the Solaris kernel. Its defining idea is the active variable: declare a variable with a class prefix such as kstat$ or kvm$ and every read of one of its members silently goes out to the kernel and fetches the current value. It powered the SE Toolkit, the standard freeware performance-monitoring kit on Solaris for roughly a decade before DTrace, and has been dormant since 2013

A concurrent research language recorded as appearing in 2001 and now dormant - and a case study in a language whose only surviving trace is its catalog entry, buried beneath a decade of unrelated software that shares its name

SORTA is the two-stack scripting language implemented by Daniel J. Bernstein's 1,542-byte C program that won Best of Show at the 8th International Obfuscated C Code Contest in 1991 - a language with features, in its author's words, "sorta from C, sorta from FORTH, and sorta from Ada", with one stack for integers, one for strings, single-character named programs, real Unix fork/exec/pipe primitives and infinite-depth tail recursion. The 2005 date attached to it in derived language lists is the day a 99 Bottles of Beer program was submitted in it, not the year the language appeared

Swym is Laurie Cheers's readability-first hobby language - pronounced "swim", short for "Say What You Mean" - designed backwards from programs its author wanted to be able to write, then reverse-engineered into something implementable. Its two signature ideas are multivalues, in which any expression may return several values that propagate through the surrounding expression, and the etc keyword, which tells the compiler to extrapolate a sequence from two or three worked examples. Its only implementation is a JavaScript interpreter that runs in a web page; it has been dormant since 2017

SmallBASIC is a free, GPL-licensed BASIC interpreter written in C that Nicholas Christopoulos began in 2000 because his new Palm IIIx shipped without a decent calculator - a QBasic-flavoured language small enough for a handheld that, a quarter of a century later, is still being released for Windows, Linux, Android and a Teensy microcontroller

A comprehensive catalog of 1,200+ programming languages from computing history, with dates, status, paradigms, and categories.