THE OPEN NOTEBOOK
A book for the curious.
70 chapters inside the Welvet AI engine. Start with why it exists, then follow the ideas into layers, learning, and the systems that connect them.
18 entries · Clear filters
III · Layers
layers/dense — MatVec microkernel
Most FLOPs are W@x. One Dense stack owns FormatNone×34 and all quants × three backends so every composite proj shares one correctness surface — including native in-dtype SGD.
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layers/mha — attention
Transformers need multi-head attention with masks, RoPE/ALiBi, GQA/MQA, and cross-attn — without forking MatVec for every projection.
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layers/swiglu — gated FFN
Modern decoder FFNs are SiLU(gate)⊙up → down. Projections must share Dense’s quant/backend matrix.
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layers/rmsnorm
Llama-style blocks normalize by RMS, not mean+var. Needs native fwd/bwd and WebGPU shaders.
Read moreIII · Layers
layers/layernorm
Classic mean+var normalization with γ/β — still required for many HF architectures.
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layers/embedding
Token IDs must gather rows from a table — not a Dense MatVec — with scatter grads on backward.
Read moreIII · Layers
layers/softmax
Classification heads and attention need stable softmax variants, including sparse/Gumbel/Entmax for research paths.
Read moreIII · Layers
layers/sequential
Some cells need an ordered Dense chain without burning grid hops.
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layers/residual
Skip connections stabilize deep stacks: y = F(x) + x with correct skip grads.
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layers/cnn1 · cnn2 · cnn3
Conv nets must sit on the same dtype×quant×backend matrix as Dense. im2col → Dense GEMV is the intentional first cut.
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layers/rnn · lstm
Sequence models before transformers still need vanilla RNN and LSTM with BPTT on the shared MatVec stack.
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layers/seqmix — mixer contract
Attention, SSM, linear attn, and conv mixers must not be accidental forks of mha. Naming the contract keeps packages honest.
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layers/gdn — gated delta net
Linear attention / decode-first mixers (Gated DeltaNet) need a first-class package under KindLinearAttn.
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layers/mamba — selective SSM
SSM mixers (KindSSM) are not MHA clones — they need their own selective-scan path.
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layers/convt1 · convt2 · convt3
Generators and U-Nets need transposed convolution as a peer of CNN, on the same Dense proj surface.
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layers/kmeans
Soft clustering as a differentiable layer lets topology experiments sit inside the same train loop.
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layers/parallel — MoE + cameral
Mixture-of-experts and multi-path cells need concat/add/avg/filter combines. Cameral graphs need sibling hemispheres that share input, merge outputs, and optionally train under distinct mode
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layers/metacognition
Observed layers can apply heuristic stability rules (gate/scale/reset) without dtype morph/QAT.
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