Segler
Edit DocLang documents
Only for Mac
Free
Mac
DocLang is the open markup format for documents that language models read and write: the structure, the text, the layout and the reading order of a document in one file, from the LF AI & Data Foundation. Most DocLang is produced by a model from a PDF or a scan, and a model is sometimes wrong: a misread line, a heading taken for a paragraph, a table cell in the wrong column.
Segler is an editor for those documents.
WHAT YOU SEE
The document as a reader would see it: headings, paragraphs, lists, tables and pictures in reading order. The element tree beside it, so the structure the model found is visible next to the text it found. The selected element's properties: its kind, its level, its label, its layer, its bounding box on the page. And when the archive carries the page images the model read, those images beside the document with the located boxes drawn over them, so a doubtful line can be checked against the page.
WHAT YOU CAN DO
Retype a line where you read it - a paragraph, a list item, a table cell. Where a line carries bold or italic, its tags are shown in the field so a correction keeps them, and so formatting can be added. Change a heading's level, or a list's or picture's class. Change a cell's kind from body to header. Correct or clear a bounding box. Change an element's label or its layer. Remove an element that should not be there. Every edit can be undone.
Segler checks the document against the DocLang specification as you work and lists what it finds, each finding a click from its element.
WHAT A SAVE DOES
Save writes the file you opened with your edits applied and nothing else changed. Markup you did not touch is written back byte for byte, including comments and whitespace. An archive's page images and assets are carried across untouched. A document you did not change is not rewritten at all.
WHAT IT DOES NOT DO
No network connection of any kind. No account. No telemetry, no analytics, no crash reporting. Nothing about you or your documents is sent anywhere, because there is nowhere for it to be sent.
It does not convert. Segler edits DocLang that already exists; producing DocLang from a PDF is a converter's job.
OPEN SOURCE
Segler is open source under the same licence as DocLang itself, and the library underneath it is a separate crate anyone can build on: github.com/excelano/segler.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Segler comes up in German on a Mac set to German: the toolbar, both panes, the dialogs and the status line. What the document says stays as the document says it. An element's name, an attribute's name and the values you choose from a list are the file's own words, and are never translated.
Selecting a heading no longer changes it. A heading whose level the element pane could not show, one the document spelled as zero or one deeper than the field's range, was rewritten to the nearest level the field could show the moment you selected it. The document was marked modified, and a save would have written that substitution to the file. Selecting an element is not an edit, and the field's range is the schema's now.
The application icon is a full-bleed square. It was a boat in a blue roundel, and because every store frames an icon in a square and rounds the corners itself, the disc read as a sticker stuck on a tile. The two document icons keep the page shape.
The developer, Excelano LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Excelano LLC
- Size
- 8.9 MB
- Category
- Productivity
- Compatibility
Requires macOS 11.0 or later.
- Mac
Requires macOS 11.0 or later.
- Mac
- Languages
- English and German
- Age Rating
4+
- 4+
- Copyright
- © 2026 Excelano LLC