{"id":26975,"library":"fa3-fwd","title":"fa3-fwd","description":"fa3-fwd provides a forward-only implementation of FlashAttention-3 for efficient attention computation on GPUs. Version 0.0.3, pre-release, no stable release cadence.","status":"active","version":"0.0.3","language":"python","source_language":"en","source_url":"https://github.com/","tags":["attention","flash-attention","gpu","cuda","deep-learning"],"install":[{"cmd":"pip install fa3-fwd","lang":"bash","label":"PyPI"}],"dependencies":[],"imports":[{"note":"Package uses underscores in module name, not hyphen.","wrong":"from fa3fwd import flash_attn_forward","symbol":"flash_attn_forward","correct":"from fa3_fwd import flash_attn_forward"}],"quickstart":{"code":"import torch\nfrom fa3_fwd import flash_attn_forward\n\nq = torch.randn(1, 8, 64, 128, device='cuda', dtype=torch.bfloat16)\nk = torch.randn(1, 8, 64, 128, device='cuda', dtype=torch.bfloat16)\nv = torch.randn(1, 8, 64, 128, device='cuda', dtype=torch.bfloat16)\n\nout = flash_attn_forward(q, k, v)\nprint(out.shape)","lang":"python","description":"Basic usage of flash attention forward pass."},"warnings":[{"fix":"Use full FlashAttention-3 library if backward is needed.","message":"Only forward pass is implemented; no backward pass. Cannot be used for training.","severity":"breaking","affected_versions":"all"},{"fix":"Pin version if stability is required.","message":"The API is experimental and may change without notice in future versions.","severity":"deprecated","affected_versions":"<1.0.0"},{"fix":"Ensure tensors are on CUDA device.","message":"Requires CUDA-capable GPU and PyTorch with CUDA. Will raise RuntimeError on CPU.","severity":"gotcha","affected_versions":"all"}],"env_vars":null,"last_verified":"2026-04-27T00:00:00.000Z","next_check":"2026-07-26T00:00:00.000Z","problems":[{"fix":"Run 'pip install fa3-fwd' and use 'import fa3_fwd' (underscore, not hyphen).","cause":"Wrong import path, missing install, or Python environment issue.","error":"ModuleNotFoundError: No module named 'fa3_fwd'"},{"fix":"Move tensors to CUDA: q = q.cuda(), etc.","cause":"Tensors are on CPU instead of GPU.","error":"RuntimeError: FlashAttention only supported on CUDA"},{"fix":"Call with three tensors: flash_attn_forward(q, k, v).","cause":"Missing required keyword arguments or too few positional args.","error":"TypeError: flash_attn_forward() missing 3 required positional arguments: 'q', 'k', 'v'"}],"ecosystem":"pypi","meta_description":null,"install_score":null,"install_tag":null,"quickstart_score":null,"quickstart_tag":null}