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Open-weight model · Image and text to text

Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX

by Elvis McFee Ecmcfee/Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX

Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX is an open-weight model for image and text to text from Elvis McFee, released under other. It has 20.9B parameters and a 262,144-token context. At 16-bit it needs about 50.2 GB of GPU memory, which fits on 1x MI300X from $1.85 an hour, at the lowest prices in the SAVRN Index.

This is a quantized MLX pack of ukisai/Swift1.5-Qwen3.8-Flash-Next — UkisAI's reasoning-efficient finetune of Qwen3.8-Flash-Next — produced by applying the MTPLX "Optimized Speed" quantization recipe from Youssofal/Qwen3.8-Flash-Next-MTPLX-Optimized-Speed to…

Parameters20.9B
Context262,144
Weights107.2 GB
Licenseother
AccessOpen weights
Monthly Downloads—

Runs On

What it takes to serve Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX (20.9B parameters): the memory its weights need at each precision, and the cheapest way to rent enough data-center GPUs to hold them.

PrecisionWeightsMemory neededCheapest setupPer hourAlso fits
16-bit 41.9 GB 50.2 GB 1x MI300X (192 GB)
Vultr
$1.85 1x H100 $1.99 · 1x MI325X $2.00
8-bit 20.9 GB 25.1 GB 1x MI300X (192 GB)
Vultr
$1.85 1x H100 $1.99 · 1x MI325X $2.00
4-bit 10.5 GB 12.6 GB 1x MI300X (192 GB)
Vultr
$1.85 1x H100 $1.99 · 1x MI325X $2.00

Memory is the weights at that precision plus 20% for the runtime and a short context; a long context needs more. Prices are the lowest on-demand hourly rates in the SAVRN Index, read Oct 16, 2026.

Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX on every accelerator the SAVRN Index prices, at every precision

Model Card

This is a quantized MLX pack of ukisai/Swift1.5-Qwen3.8-Flash-Next — UkisAI's reasoning-efficient finetune of Qwen3.8-Flash-Next — produced by applying the MTPLX "Optimized Speed" quantization recipe from Youssofal/Qwen3.8-Flash-Next-MTPLX-Optimized-Speed to the Swift-1.5 weights. It was forged locally with mtplx forge (MTPLX 2.12.2, qwen4-exp lane) from source revision 0bd4fe22431372cdad1979267d3ab45aa7e6150a, full-load verified before stamping, and runs with MTP draft-acceptance active and the n-gram table offloaded to SSD — the same target class as the original pack: M5 Ultra 96 GB or M5 Max 128 GB Macs with fast NVMe storage. Note vs the original Youssofal pack: this build runs qsa8bit…

Excerpt from the card by Elvis McFee, licensed other.

Configuration

Architecture
Qwen4ExpForConditionalGeneration
Context length (tokens)
262,144
Layers
48
Hidden size
2,560
Attention heads
24
Key/value heads
2
Head dimension
256
Vocabulary size
248,320
Experts
512
Experts active per token
10
Model type
qwen4_exp

Identity and Version

Repository
Ecmcfee/Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX
Publisher
Elvis McFee
Task
Image and text to text
Modality
Image and text
Library
mlx-lm
Parameters
20.9B parameters
Languages
mlx-lm, mlx, mtp, moe
Revision
4a5daad54dddb23e5454bfb30211f5cd7d2e6645
First published
2026-10-15
Last updated
2026-10-15

Files and Weights

36 files, 107.2 GB in total. The weights are 22 files totalling 107.2 GB in safetensors.

Weights22 files · 107.2 GB
Configuration7 files · 360.0 KB
Tokenizer4 files · 30.1 MB
Documentation1 file · 4.0 KB
Other1 file · 9.0 KB
Repository1 file · 1.6 KB
Every file
FileTypeSizeSHA-256
model-00001-of-00019.safetensorsWeights4.2 GB b995a152a046
model-00002-of-00019.safetensorsWeights4.0 GB 6aef82bc6494
model-00003-of-00019.safetensorsWeights3.9 GB 16770d885ec5
model-00004-of-00019.safetensorsWeights4.0 GB e90e601ef947
model-00005-of-00019.safetensorsWeights4.0 GB 2d7f616b7452
model-00006-of-00019.safetensorsWeights3.9 GB 756e4c250493
model-00007-of-00019.safetensorsWeights4.0 GB 01fa8d410816
model-00008-of-00019.safetensorsWeights4.0 GB 9158239adf02
model-00009-of-00019.safetensorsWeights3.9 GB 46f4478b5a40
model-00010-of-00019.safetensorsWeights4.0 GB b94eb862b280
model-00011-of-00019.safetensorsWeights4.0 GB a2c4cdcb41be
model-00012-of-00019.safetensorsWeights3.9 GB 09fb54445c2f
model-00013-of-00019.safetensorsWeights4.0 GB 1bd2665bcb78
model-00014-of-00019.safetensorsWeights4.0 GB b7d3f22aed56
model-00015-of-00019.safetensorsWeights3.9 GB 199fe96df97a
model-00016-of-00019.safetensorsWeights4.0 GB 54e14758c202
model-00017-of-00019.safetensorsWeights4.0 GB 719e410256e3
model-00018-of-00019.safetensorsWeights3.9 GB 5952ab703ce3
model-00019-of-00019.safetensorsWeights1.2 GB fbde36c73b5d
model-vision.safetensorsWeights897.9 MB 5aff6983f36f
mtp.safetensorsWeights1.5 GB bcc290d37a6d
ngram-table.safetensorsWeights32.0 GB db2b050c3f5a
config.jsonConfiguration68.8 KB —
generation_config.jsonConfiguration202 B —
model.safetensors.index.jsonConfiguration284.9 KB —
mtplx_runtime.jsonConfiguration4.9 KB —
preprocessor_config.jsonConfiguration390 B —
processor_config.jsonConfiguration367 B —
video_preprocessor_config.jsonConfiguration385 B —
README.mdDocumentation4.0 KB —
chat_template.jinjaOther9.0 KB —
.gitattributesRepository1.6 KB —
merges.txtTokenizer3.4 MB —
tokenizer.jsonTokenizer20.0 MB 06b9509352d2
tokenizer_config.jsonTokenizer1.1 KB —
vocab.jsonTokenizer6.7 MB —

License and Download

License
other
Access
Open weights, no gate
Download size
107.2 GB
Download from Elvis McFee

Released by Elvis McFee through its official repository on Hugging Face. Read the license.

Built From

  • Derived from ukisai/Swift1.5-Qwen3.8-Flash-Next
  • Quantized from ukisai/Swift1.5-Qwen3.8-Flash-Next

Memory Requirements

PrecisionWeights in memory
As published107.2 GB
16-bit41.9 GB
8-bit20.9 GB
4-bit10.5 GB

Weights only, from the published parameter count; the key-value cache and runtime add to this.

Questions About Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX

How much GPU memory does Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX need?

About 50.2 GB at 16-bit and 12.6 GB at 4-bit: the weights (20.9B parameters) plus a working margin. A long context needs more.

What is the cheapest GPU to run Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX on?

At 16-bit, 1x MI300X from $1.85 an hour; at 4-bit, 1x MI300X from $1.85 an hour, at the lowest on-demand prices the SAVRN Index lists.

What license is Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX released under?

other, as its publisher declares it. Read the license text before commercial use.

What is Swift1.5-Qwen3.8-Flash-Next-q4-MTPLX's context length?

262,144 tokens, from the maximum position embeddings in its published configuration.

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