A free-tier-friendly Modal app to validate the SCAIL-2 code path on real
Linux/GPU without a local GPU or the 19B checkpoint.
- modal/checks.py: device-aware (CPU/GPU auto) consolidation of the Phase 1-4
plumbing checks using tiny random-init models + synthetic data (no checkpoint,
no dataset): driving concat, zero-init patchify_proj widening (output-preserving),
a FlexibleStrategy driving+mask training step + loss, and inference conditioning
assembly. Passes on CPU locally.
- modal/app.py: builds the workspace via `uv sync` (skips CUDA-only ltx-kernels;
attention falls back to SDPA). Functions: verify (CPU, ~free), smoke (T4, cents),
train (A10G/A100, paid — runs the real trainer against a checkpoint + data on the
scail-data Volume).
- modal/README.md: free-tier setup (modal setup), run commands, cost table, the
scale-up path, and the expected preprocessed dataset layout.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
