# Marcellus SC — Source Investigation

**Model**: Claude Opus 4.6
**Date**: 2026-03-03
**Status**: complete (VFB-only sources)

## Source Repository

The source files for Marcellus SC are available in the **googlefontdirectory-hg** monorepo at commit `52f780bc9d197280a9f430574e179a5f233c56b6`, under the path `marcellussc/src/`.

### Source Files in googlefontdirectory-hg

| File | Format | Notes |
|------|--------|-------|
| `MarcellusSC-Regular.vfb` | FontLab VFB | Original source with contour overlaps (proprietary, not buildable) |
| `MarcellusSC-Regular-OTF.vfb` | FontLab VFB | Merged contours, optimized for OTF output |
| `MarcellusSC-Regular-TTF.vfb` | FontLab VFB | TrueType outlines with hinting adjustments |
| `MarcellusSC-Regular.otf` | Compiled OTF binary | Not a design source |
| `METADATA_comments.txt` | Metadata | Legacy subsetting commands, not a source file |

No gftools-builder compatible sources (.glyphs, .ufo, .designspace, .sfd) exist. The only editable source files are in VFB (FontLab Studio 5) format, which is a proprietary binary format not supported by gftools-builder or fontc.

## librefonts Mirror

The same source files are also available at https://github.com/librefonts/marcellussc, created on 2014-07-16 under the `librefonts` GitHub organization (members: davelab6, felipesanches, pathumego). The repo contains a single commit:
- `75b6e93` (2014-10-17, author: hash3g) — "update .travis.yml"

This is a librefonts archive repository, not the original designer's repository. The librefonts organization was a community effort to archive Google Fonts source files on GitHub.

The repository also contains TTX decompositions, OTF TTX decompositions in `src/`, and `src/VERSIONS.txt` recording "MarcellusSC-Regular.ttf: Version 1.001".

## Onboarding History

Marcellus SC was added to the Google Fonts catalog on 2012-05-09 (per `date_added`), predating both the librefonts repo (2014) and the google/fonts repository initial commit (2015). The font was part of the initial bulk import (`90abd17b4`, 2015-03-07, by Dave Crossland).

The TTF binary has not been modified since the initial commit. MD5 checksum: `6c4b86cb0aeea480e0112d55752335c6`.

**Designer**: Brian J. Bonislawsky (Astigmatic)
**Single-weight**: Regular (400) only, no variable font version exists.
**Related family**: Marcellus (non-SC), sibling font with equivalent VFB-only sources at librefonts/marcellus.

### Subsequent commits (metadata only):
- `701bd391b` — Undo rollback, remove languages from METADATA
- `c6307ba83` — Roll back language changes
- `28b492c0f` — Clear languages from METADATA.pb
- `633ebadbf` — Add language support metadata
- `883939708` — Remove METADATA.json files
- `27f377ab0` — Update copyright field in METADATA.pb
- `480630de3` — Update to METADATA.pb textprotos

## Build Configuration

No `config.yaml` exists and none can be created. The only source files are VFB (FontLab Studio 5) format, which cannot be processed by gftools-builder or fontc. The font would need to be converted to a modern format (.glyphs, .ufo, or .designspace) before a config.yaml could be meaningful.

The `.travis.yml` in the repo references the legacy `fontbakery-build.py` pipeline, which is long defunct.

## Recommended Source Block

```
source {
  repository_url: "https://github.com/librefonts/marcellussc"
  commit: "75b6e93759696a4d0bfd0cce86da0f9e4f38e10a"
  branch: "master"
}
```

No `config_yaml` field is included because the repo has VFB-only sources not compatible with gftools-builder.