HyMo-434M — documentation portal

A 434M-active / 1.13B-stored hybrid language model: Gated Delta Networks (linear attention) interleaved 3:1 with Multi-Head Latent Attention (full attention), routed through a 16+1 Asymmetric Mixture-of-Experts. Pure PyTorch — one hand-written Triton GDN recurrence kernel, a NorMuon + AdamW dual optimizer, and a 30B-token training target.

HYBRID RATIO
75% SUB-QUADRATIC
3:1 stack ratio · 24 GDN linear layers + 8 MLA full-attention layers
ASYMMETRIC FFN
16+1 TOP-2 MoE
Sparse MoE (2304d) on 8 MLA blocks; 24 GDN blocks are recurrence-only (no FFN)
DUAL OPTIMIZER
NorMuon + AdamW
NorMuon for 2D matrix weights; Cautious AdamW for 1D, Embeddings & MoE
MTP PREDICTION
2 HEADS [0.3, 0.1]
Multi-Token Prediction auxiliary heads accelerate representation learning
FIG. A0 HYBRID RECURRENCE FIELD · GDN · MLA · MoE 32 LAYERS · 896 DIMS · 16 HEADS
01 · params
~750M
02 · layers
32 24+8 (3:1)
03 · attention
MLA 4 KV grp
04 · recurrence
GDN chunk 64
05 · ffn
16+1 MoE / SwiGLU
06 · vocab
64,256 BPE-64k
07 · ctx & rope
4096 25% decoupled
08 · optimizer
Dual NorMuon+AdamW
§ HYMO CORE MECHANISMS · INTERACTIVE BENCHMARK LABS
01 · GDN RECURRENCE Fused 1D Selective Scan

Gated Delta Net processes linear recurrence with sub-quadratic O(N) complexity. Learned decay α_t = exp(g_t A) and write/read state decomposition.

Recurrence Chunk Size: 64 tokens / chunk
DELTA RULE h_t = (1 - β_t q_t k_t⊤) h_{t-1} + β_t v_t k_t⊤
TRITON KERNEL Fused 1D selective scan with chunked recurrence (Q=64)
Sub-Quadratic Ratio: 24 of 32 Layers (75% Stack)
Numerical Parity: < 1e-5 max |Δ| vs Eager
02 · ASYMMETRIC MoE 16+1 Router on MLA Layers

DeepSeekMoE with 16 routed experts (2304d) + 1 shared expert (2304d). Top-2 routed per token with aux-loss-free dynamic bias leveling Δb.

Active Experts: #02, #07 + shared (2304d)
FFN Placement: MLA Only (GDN blocks are recurrence-only, no FFN)
03 · MLA COMPRESSION 4 KV Groups Footprint Analyzer

Multi-Head Latent Attention compresses KV cache to 4 groups (128 latent + 32 rope dims). Reduces KV cache footprint by 16× per layer vs standard MHA.

Context Length: 32,768 tokens
Standard MHA (16 heads × 128d × 32L): 8.00 GB
HyMo Hybrid (24 GDN + 8 MLA): 0.13 GB
KV Cache Memory Saved: 7.87 GB (16× cut per layer)
04 · MTP SPECULATION Depth-2 Speculative Tree

Multi-token prediction. Main 32-layer backbone predicts token t while depth-1 and depth-2 modules draft candidate tokens t+1 and t+2 with shared embeddings.

MAIN HEAD Token t → "architectures" (p = 0.99)
MTP DRAFT 1 Token t+1 → "converge" (p = 0.88 ≥ 0.80)
MTP DRAFT 2 Token t+2 → "faster" (p = 0.82 ≥ 0.75)
Speculative Verification: ACCEPTED (3 Tokens / Step)
Throughput Acceleration: 2.00× effective speedup
FIG. A1 FULL TRAINING STEP PIPELINE 32 LAYERS · FORWARD · AUTOGRAD · DUAL OPTIMIZER
§ core

Core Architecture

§ concepts

Architecture & Concepts

§ guides

Guides & Playbooks

§ refs

API References