Fix Modal fine-tuning scripts for YOLO26n and MiniCPM-V before running
Session from kirana-detective-build-traces on Hugging Face by build-small-hackathon · MIT · condensed by Coders Talk
Review three Modal fine-tuning scripts (YOLO26n, MiniCPM-V 4.6, MiniCPM5-1B) against current June 2026 official docs before running them, and fix any bugs so they run cleanly on Modal.
- +0Prompt · +0Check the three finetune scripts (YOLO26n, MiniCPM-V, MiniCPM5-1B) before I run them on Modal — research official June 2026 MiniCPM training docs and confirm the scripts are correct.
- +0mAgent did · +0mRead all three fine-tune scripts and dispatched research subagents to check current Unsloth VLM patterns and MiniCPM-V/MiniCPM5-1B status as of June 2026.
- +2mAgent did · +2mApplied fixes across all three scripts: corrected pip extras/version pins, fixed image-path vs PIL Image handling, added missing UnslothVisionDataCollator, and fixed ONNX export path capture in the YOLO script.
- +12mFail · +12mmodal run of train_minicpm_v.py failed during image build with repeated apt-get 404 errors from a stale Debian bookworm package index.
- +13mAgent did · +13mDiagnosed that .run_commands("apt-get install...") skipped apt-get update; switched to Modal's .apt_install() which refreshes the index, and dropped the unneeded ffmpeg dependency.
- +21mFail · +21mImage built successfully but training crashed with a pyarrow ArrowInvalid error — PIL Image objects could not be serialized into the HuggingFace Arrow dataset.
- +22mAgent did · +22mReworked the dataset build to store image file paths in a separate 'images' column, cast it with datasets.Image(), used a {'type':'image'} placeholder in messages, and relied on UnslothVisionDataCollator to pair them at training time — the standard Unsloth VLM pattern.
- +22mOutcome · +22mSession ends with the dataset-format fix applied and a retry of 'modal run finetune/train_minicpm_v.py' queued; two build/runtime failures (apt 404s, Arrow/PIL serialization) were diagnosed and fixed in sequence.
Next time I'd ask it to actually dry-run or at least trace the Modal image build and dataset serialization steps against Unsloth's current examples, not just review the code — the static review missed both the apt-get ordering bug and the PIL/Arrow serialization issue, which only showed up once I actually ran it on Modal. The fix that did the real work was switching to .apt_install() for a fresh package index and moving images into a separate datasets.Image() column instead of embedding PIL objects directly.