Comments

• By _the_inflator 2026-02-115:254 reply

  Someone has to do it:

  Please auto-ban any "We gave Claude/Gemini/Grok/OpenAO/Qwen/Mistral/WhateverLLMAI the spec and..."

  "and..." resolves to:

  - "and now we have this impressive result you won't believe!"

  100% of the time this is attention seeking, live debugging - no value at all.

  Don't waste people's time. Any sound and reasonable story about results without misusing the public's eye is welcome, for example:

  - One year after - 10 hard problems we found - extensive pro/contra comparison with other solutions - maintaining such a AI app for one year

  Otherwise: please auto-ban.

  By illright 2026-02-1116:54

  I disagree that this submission has no value at all or that it should be auto-banned — there is a difference between thoughtless vibe-coding and spec-driven coding, guarded by tests. It seems from the next thread that this project is hopelessly outmatched by the sheer complexity of taking on something as the Docx spec, but this project has value, and for someone, it may be all that they need.

  However, I do agree with your point about live debugging. In light of that, I prefer to treat this submission as a curiosity about current model capabilities, and let the authors keep improving this project if they find it worth their time.

  Let's be more respectful to the differing goals of people

  By efilife 2026-02-116:05

  Seconded. I could ask the LLM myself and see what it comes up with in 5 minutes, not to mention that all of this was done 1000 times already so I have no interest of doing so.

  Also, it's effortless. Not interesting at all if you can't share any insight about the project, because you don't know how it works under the hood and how many architectural problems were solved (or not)

  By ramon156 2026-02-1111:161 reply

  At this point I agree, this is brogramming and its getting boring.

  By KellyCriterion 2026-02-1116:32

  > brogramming

  Is it back? I remember 2011 it had a high time in an ad agency I was working back then :-D

  By lelanthran 2026-02-1110:12

  The real tragedy is that I can only give a single upvote. This post needs to be added to the HN guidelines, I feel.

  We are being overwhelmed with slop. Not even original slop, but carefully specced slop that poorly replicates some existing functionality, but as a SaaS.

  This is the 90s equivalent of "Doing $FOO, but on the internet", only it's "Copying $FOO, but with added costs as a SaaS".

  That it is AI is just another black mark against it.

• By mediumdeviation 2026-02-1023:125 reply

  Ah these poor fools. Having built this exact product (OOXML compatible editor in React) before, it took all of two minutes to find a bug. The issue is that the OOXML spec is not in fact definitive - Word is, and trying to implement it from the spec will produce something that works maybe 80% of the time then fall over completely when you hit one of hundreds of minor, undocumented edge cases. Assuming of course that CC did not just hallucinate something. And then there's the more fundamental problem that HTML/CSS has unresolvable incompatibilities with OOXML. This is why Google Docs for instance use canvas for rendering.

  By jimjimjim 2026-02-112:573 reply

  I feel your pain. PDF applications have the same problem. The thousand page PDF spec isn't actually the spec, Acrobat is the spec.

  By FranklinJabar 2026-02-119:351 reply

  Acrobat at least hasn't been relevant for over a decade outside of niche concerns (like javascript-enabled pdfs, which I have seen exactly twice in the wild... these should be illegal by the way). You can't say the same about microsoft.

  By skeeter2020 2026-02-1115:30

  This is not true IME, because PDF and PostScript are so tightly coupled. If your PDF renderer doesn't tightly align with Acrobat, it's highly likely to not print correctly, hence Acrobat __is__ the spec.

  By pryelluw 2026-02-116:18

  I feel the pain having had to build a browser based pdf editor with features not found anywhere else. React was hammered into working and turned out pretty good. But my god, it was quite a journey. As with all enterprise projects, this one was shelved because business changed their minds. Two years of figuring it out just wasted …

  By throawayonthe 2026-02-117:531 reply

  do people still use acrobat? since pds becoming prolific in browsers and word and stuff i mean

  By k4rli 2026-02-1112:32

  IE was used well until EOL and is still being used in some places. I have no doubt Adobe Acrobat is the same way. Likely few if any new users but old ones will keep using what they're familiar with.

  By Tade0 2026-02-1111:43

  When I saw the title I couldn't help but ask myself: how?

  The spec is over 5000 pages long - no way in hell a human could parse this in a reasonable timeframe and no agent today has nearly the necessary context.

  EDIT: also, like you said: the spec is secondary to the implementation and was only published (and not even in complete form originally!) because Microsoft was asked by the EU to do that.

  By thisisjedr 2026-02-1023:491 reply

  Fair point, we know the editor isn't yet 1:1 with Word. When you built yours, was Word your source of truth (reverse-engineering sense), or did you stick to MS-OE376? And any recommended process for systematically uncovering those undocumented edge cases?

  By mediumdeviation 2026-02-110:331 reply

  We went out and used our editor against our and customer's documents. The Open part of OOXML makes as much sense as the Open in OpenAI. Microsoft made OOXML available to fend off an antitrust lawsuit, there is no incentive for them to make it actually easy to build competing editors off their specification.

  FWIW the bug I found is that your comment parser assumes the w:date attribute represents a useful timestamp of when comments are made. It does not - a bug in Word causes it to save it as ISO8601 local time but _without timezone_, rendering it useless if more than one user across different timezone edits the document. Instead, you need to cross reference the comment with a newer comment part and find a dateUtc attribute. The above is, of course, completely undocumented.

  By mickael-kerjean 2026-02-112:47

  Can you say the name of the editor your worked on?

  By nayroclade 2026-02-111:212 reply

  When you built this exact product, how long did it take you to reach 80% compatibility?

  By skeeter2020 2026-02-1115:31

  >> how long did it take you to reach 80% compatibility?

  Honest question: when the formal spec isn't really a spec how do you even measure "80% compatibility"?

  By thisisjedr 2026-02-111:441 reply

  We don’t have a formal '% compatibility' metric yet, but it’s on our radar as a feedback loop mechanism for self-improvement.

  For now, we mostly rely on testing with our own and customer docs. In practice, we were seeing solid results after a couple of days of keeping Claude working in the loop and giving lots of feedback: .docx files along with screenshots annotated to highlight what didn’t work.

  By ramon156 2026-02-1111:18

  This is a very naive mindset, getting the last 10% is going to be 90% of the work. Learn from other projects that have tried and failed. I can guarantee you LibreOffice was not built with "our own and customer docs" as a test harness.

  By KellyCriterion 2026-02-1116:34

  Arent there any commercial libraries available already?

  Somehow this reminds me of PDF

• By bonesss 2026-02-116:291 reply

  > As an experiment

  The threshold for caring about experiments is exponentially higher in 2026 thanks to half baked vibe slop.

  Non-functioning software and demoware comes fast and cheap, regardless of author.

  > we gave Claude Code the OOXML spec

  Having used the former a lot and read the latter in detail, uhhh…

  Trim down the claims here, clarify the editor subset you plan to be supporting, and map the “last 90%”’s to honestly reflect the product you are pushing.

  If “tables” and “images” aren’t there I’m quite skeptical about content controls and other key OOXML constructs being addressed meaningfully. The full OOXML footprint chokes OpenOffice out of procurements, rich OOXML documents choke half-way-there implementations (which was the whole point of the format).

  As is pointed out elsewhere in the thread - there are fundamental constraints that have kept Google, Apple, and others from pursuing this route. Relatively simple docs are one thing, but OOXML is full of dragons and parity with Word has eluded more than a few tech giants.

  By lelanthran 2026-02-1110:23

  I agree with everything in this comment - FWIW, I was on the standards bodies in my country in 2008/2009 to establish a national standard for word processing documents.

  We debated the OOXML spec in as much detail as time allowed, but we still didn't get through the entire behemoth of a thing.

  ISTR that Microsoft representatives were also on the same subcommittee, and, but the MS rep was pushing very hard indeed to standardise on OOXML.

  Too bad the OOXML format, itself, has MS-proprietary binary blobs built into the specification as part of the format.

  ISTR we submitted a recommendation of standardising on ODF.