-# Ruluko — Upstream Source Investigation
+# Ruluko — Source Metadata Investigation
-**Designer**: Ana Sanfelippo, Angélica Díaz, Meme Hernández
**Model**: Claude Opus 4.6
**Date**: 2026-03-12
-## Summary
+## Source Repository
-No canonical upstream repository with UFO or Glyphs source files was found for Ruluko.
+The `googlefontdirectory-hg` monorepo (the historical Google Font Directory Mercurial archive) contains files for this family.
-## Investigation
+- **Repository**: `googlefontdirectory-hg`
+- **Commit**: `52f780bc9d197280a9f430574e179a5f233c56b6`
+- **Source path**: `ruluko/src/`
+
+## Source Files
+
+The `ruluko/src/` directory contains design sources in VFB (FontLab) and SFD (FontForge) formats, neither of which can be built with gftools-builder:
+
+- **VFB** (FontLab, proprietary format, not buildable with gftools): Ruluko-Regular-OTF.vfb, Ruluko-Regular.vfb
+- **SFD** (FontForge, not buildable with gftools-builder): Ruluko-Regular-TTF.sfd
+- **OTF** (compiled binaries, not design sources): Ruluko-Regular.otf
+
+## Buildability
+
+Not buildable with gftools-builder. The sources are in VFB (FontLab proprietary) and SFD (FontForge) formats. Neither format is supported by gftools-builder. Conversion to UFO or Glyphs format would be required.
+
+## Designer
+
+Ana Sanfelippo, Angélica Díaz, Meme Hernández
+
+## Investigation Details
Ruluko was designed by Ana Sanfelippo (Twitter: @anasanfelippo), Angélica Díaz (@angiecinadiaz), and Meme Hernández (@memepeca) as a typeface intended to aid those learning to read, with shapes related to handwriting styles used in Argentine schools.
- `google-fonts-bower/ruluko-bower` — a bower packaging repo (skipped)
No GitHub account was found for any of the three designers. The DESCRIPTION.en_us.html and FONTLOG.txt contain no upstream source repository links.
-
-## Conclusion
-
-No canonical upstream repository with editable UFO or Glyphs sources was found for Ruluko. No source block was added to METADATA.pb.