Xerdi xerdi.com

Work

Evidence, not adjectives

A capability list costs nothing to write. These are the problems I was actually handed, and what changed as a result.

Selected work

  • A compliance knowledge base that keeps its provenance

    A regulatory-compliance venture

    Regulatory material — AI Act, GDPR, GxP — assembled into a corpus that can be searched and cited. The design rule was that a retrieved answer must always be traceable to the passage it came from: deterministic where the answer is a fact, human-validated where it is a judgement.

    Corpus engineeringRetrievalRegulatory text

  • XDP — the document tooling behind all of it

    Xerdi

    A LuaLaTeX document framework with a validated data/schema separation: a recipe declares the fields a document accepts, a payload supplies them, and a document that is handed the wrong data fails to build instead of printing it. Every quote, invoice and handbook Xerdi issues is produced by it. It is tooling and not a service: it runs on the machine in front of you. XDAP is the platform built on top of it.

    LuaLaTeXSchema validationPDF/A-4fReproducible builds

    Read where it is written down

  • XDAP — the platform that issues the documents

    Xerdi

    The platform built on XDP: a document type declares the input it accepts, the input is validated before anything is typeset, and what comes back is a PDF/A-4f file with the validator's report beside it. What it issues carries a detached signature, and the key to check that is published here rather than only on the platform — a key served by the machine that served the document proves nothing.

    Document pipelinePDF/A-4fDetached signaturesValidated input

    See it build a document

Why some clients are not named

Naming a client on a public page is their decision, not mine. Where I have their agreement on record, I name them. Where I do not, the work is described without them — which costs a little credibility and is still the right way round.

If you are a client and would like your project named here, or named differently, tell me and it changes.

Who does this

Xerdi is one engineer, which is a fair thing to want to check before handing over a document estate. The record is public and it is not kept here: the packages on CTAN, the papers in TUGboat and MAPS, the talks, and a list of what Erik has worked on and for whom.

It sits on his own site rather than this one because it is his and not the company's. It is linked because you are entitled to read it before deciding.

Erik's own record

Yours could be the next one

Most of this work started as a document that kept going wrong. Send me yours.

Write to Erik