[okfn-labs] Free spreadsheet softwares that are easy to extend

[Thomas Levine]

I'm looking for a free spreadsheet software in which I can
easily write my own functions. Does anyone have any ideas?

I've been using Gnumeric, but it's quite buggy and poorly
documented.

I'm going to look next at Calligra, sc, Dismal mode, Esheet,
jQuery.sheet, and sheetjs.
http://dada.pink/notes/spreadsheet-softwares/

Is there anything else I should consider?

Thanks

Tom