April 11, 2026
Summon the arrays, mind the runes
The APL Programming Language Source Code (2012)
IBM’s 60s math-wizard code drops — magic spell or just weird symbols
TLDR: The Computer History Museum released IBM’s late‑60s APL/360 source code for non‑commercial use. Commenters split between awe at its “one‑line magic” and jokes about unreadable symbols, turning the drop into a nostalgia fest and a debate over brilliance versus practicality in old-school, math-heavy coding.
IBM’s 1969–72 APL/360 source code just landed via the Computer History Museum, and the comments went full campfire legend. APL, a math-first “array” language created by Kenneth Iverson, used a zoo of symbols and even ran interactively on shared mainframes — and the crowd can’t decide if it’s genius spellbook or keyboard hieroglyphics.
One camp is enchanted. A commenter called it “a kind of sorcery,” while another bragged that a finance pro in the 90s crunched a risk dataset into a single line, like prehistory’s Jupyter. APL superfans say it warps your brain in the best way: once you think in arrays, everything else feels clunky. Cue the memes: “summoning circles,” “magic runes,” and “poetry you can’t read.”
But skeptics clap back with reality checks. One veteran admits that in 43 years, they only ever saw one APL user — niche much? Others joke that APL looks like The Matrix fell on a keyboard. The middle ground calls it a beautiful relic: written in gritty assembly, powering its own timesharing system, now released for non-commercial tinkering. HN’s hall monitor even chimed in with a link to the last big thread, because of course they did. Verdict: a glorious, unreadable treasure map everyone wants to peek at, few will actually follow.
Key Points
- •Computer History Museum released the 1969–1972 “XM6” APL for System/360 source code for non-commercial use.
- •APL originated as Kenneth E. Iverson’s 1957 mathematical notation at Harvard and became a programming language by 1966.
- •IBM’s APL\360 provided an interactive, timeshared environment on the System/360, unusual for its era.
- •APL\360 was written entirely in 360 assembly and implemented a complete timesharing OS in addition to the language.
- •The released source comprises 37,567 lines across 90 files; access requires accepting a license that prohibits commercial use and reposting.