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25 concepts

Architecture concepts

The design ideas that keep showing up across the gallery: what each one does, what it costs, and which models use it.

Attention

  • MHA4 models

    Multi-Head Attention

    The original transformer attention: every head has its own queries, keys and values.

    First here: GPT-2 XL 1.5B · Nov 5, 2019

  • GQA78 models

    Grouped-Query Attention

    Several query heads share one key/value head, shrinking the KV cache with little quality loss.

    First here: Llama 3 8B · Apr 18, 2024

  • MLA28 models

    Multi-Head Latent Attention

    Keys and values are compressed into a small latent vector that is cached instead of full K/V.

    First here: DeepSeek V3 · Dec 26, 2024

  • SWA38 models

    Sliding Window Attention

    Some layers only attend to a local window of recent tokens instead of the whole context.

    First here: Gemma 3 27B · Mar 11, 2025

  • Attention budgeting3 models

    Layer-wise attention budgeting

    Different layers get different attention budgets: head counts, windows or full context.

    First here: Laguna XS.2 · Apr 28, 2026

  • Gated attention21 models

    Gated Attention

    A learned sigmoid gate scales the attention output before it re-enters the residual stream.

    First here: Qwen3 Next 80B-A3B · Sep 9, 2025

  • Hybrid attention24 models

    Hybrid Attention

    Mixes cheap linear-attention or state-space layers with a few full-attention layers.

    First here: Qwen3 Next 80B-A3B · Sep 9, 2025

  • ShortConv10 models

    Short Convolution

    A tiny causal depthwise convolution (kernel ≈ 4) that mixes each channel over the last few tokens.

    First here: Kimi Linear 48B-A3B · Oct 30, 2025

Sparse & compressed attention

  • DSA10 models

    DeepSeek Sparse Attention

    A lightweight indexer scores past tokens and each query attends only to its top-k picks.

    First here: DeepSeek V3.2 · Dec 1, 2025

  • IndexShare3 models

    IndexShare

    Nearby layers reuse the token selection computed by one DSA indexer.

    First here: GLM-5.2 · Jun 17, 2026

  • QSA1 models

    Qwen Sparse Attention

    Like DSA, but the indexer picks whole four-token blocks rather than single tokens.

    First here: Qwen3.8-Flash-Next 125B-A6B · Aug 26, 2026

  • CSA / HCA2 models

    Compressed Sparse & Heavily Compressed Attention

    Pool groups of older tokens into fewer KV entries, compressing along the sequence axis.

    First here: DeepSeek V4-Pro · Apr 24, 2026

  • CCA1 models

    Compressed Convolutional Attention

    Attention computed directly in a compressed latent space, with convolutional mixing.

    First here: ZAYA1-8B · May 6, 2026

Feed-forward & experts

  • MoE79 models

    Mixture of Experts

    Many feed-forward experts, but a router sends each token to only a few of them.

    First here: DeepSeek V3 · Dec 26, 2024

  • Latent MoE5 models

    Latent MoE

    Routed experts operate in a smaller latent space instead of the full hidden width.

    First here: Nemotron 3 Super 120B-A12B · Mar 11, 2026

  • PolyNorm1 models

    PolyNorm

    A learned activation mixing normalised linear, quadratic and cubic terms.

    First here: Motif 3 Beta · Jul 21, 2026

Residual stream

  • mHC6 models

    Manifold-constrained Hyper-Connections

    Several parallel residual streams with learned, constrained mixing between them.

    First here: DeepSeek V4-Pro · Apr 24, 2026

  • GR1 models

    Gated Residuals

    Gated read/write modules over four residual streams, without mHC's mixing matrix.

    First here: Qwen3.8-Flash-Next 125B-A6B · Aug 26, 2026

  • AttnRes3 models

    Attention Residuals

    Learned, attention-style weights over earlier layer outputs replace the plain residual sum.

    First here: Kimi Linear 48B-A3B · Oct 30, 2025

  • Looped depth3 models

    Looped Transformer

    The same blocks are applied several times, reusing weights across depth.

    First here: Ouro-Thinking 2.6B · Oct 29, 2025

Positions & normalization

  • QK-Norm40 models

    QK-Norm

    RMSNorm applied to queries and keys before attention to keep logits well-behaved.

    First here: OLMo 2 7B · Nov 25, 2024

  • NoPE18 models

    No Positional Embeddings

    Some or all layers drop explicit positional encodings and rely on the causal mask.

    First here: SmolLM3 3B · Jun 19, 2025

Efficiency & sharing

  • KV sharing4 models

    Cross-Layer KV Sharing

    Later layers reuse key/value states produced by earlier layers.

    First here: Gemma 4 E4B · Apr 2, 2026

  • PLE3 models

    Per-Layer Embeddings

    Each layer gets its own token-specific embedding signal from a large lookup table.

    First here: Gemma 4 E4B · Apr 2, 2026

Training objectives

  • MTP34 models

    Multi-Token Prediction

    Extra heads learn to predict several future tokens, and can draft tokens at inference.

    First here: DeepSeek V3 · Dec 26, 2024

Reference pages on the source gallery

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