Hi HN, author here. This builds on the very same AutoLISP Interpreter, i did for: https://news.ycombinator.com/item?id=46393271

The Lisp can be used to define the GLDF product in the LISP REPL, some files are in the wasm bundle, so for the demo you can simply: Click the [λ Script (Lisp)] Button and it will create the GLDF as defined in the LISP, and also start some Animation, tilting the light fixtures, changing Variants (and as such housing and light color) and some camera movement

As the title as well mentioned IFC, here how to create the Quonset Hut on bimifc.de (same engine as acadlisp.de)

(ifc-new) (ifc-set-project "Quonset Hut" "Airfield" "Hangar" "GF" "Engineer" "Corps") (ifc-storey "Ground Floor" 0.0) (ifc-add-slab 0 0 8 15 0.2 0 "Concrete Pad") (ifc-add-wall 0 0 8 0.15 4.0 0.2 "Front Wall") (ifc-add-wall 0 14.85 8 0.15 4.0 0.2 "Rear Wall") (ifc-add-door 3 0 2.0 0.15 3.0 0.2 "Hangar Door") (ifc-add-window 1 14.85 1.5 0.15 1.5 0.2 "Rear Window") (ifc-storey "Roof" 4.0) (ifc-add-roof-barrel 0 0 8 15 3.0 4.0 "Steel Arch")

Forgot to mention: it is all Open Source and on crates.io: github.com/holg (acadlisp, bimifc, gldf-rs)