GLM-5.3-Flash-4bit-paged
Expert-paged build of pipenetwork/GLM-5.3-Flash-MLX-4bit. The weights that are read a fraction at a time
live in their own containers, so a machine loads what it needs rather than all
of it.
| file | size | holds |
|---|---|---|
model.safetensors | 5.89 GiB | resident weights |
experts.bin | 159.47 GiB | routed experts |
mtp/ | 3.90 GiB | draft head, off by default |
Total 169.27 GiB. Of that, 165.37 GiB is the source build, whose bytes moved into
These containers are not a format mlx-lm reads. The model runs on
gbx_lm, a single signed binary for Apple Silicon; there is nothing to
pip install.
containers rather than being copied, and 3.90 GiB is the draft head, which no
published build of this model carries.
Requirements
| macOS | 15.0 or later |
| chip | Apple Silicon (arm64). There is no Intel build. |
| Python | none -- the binary carries what it needs |
Memory is not a fixed figure for a paged build, and that is the point of one: it fills what fits and streams the rest from disk. On a 512 GB Mac Studio with room to spare this model settles at about 172 GB resident. A smaller machine holds less and reads more from disk -- slower, but it runs.
How much slower depends on how far the machine is from holding the experts, and on how fast its disk is. Each token routes to a few experts; the ones already in memory cost nothing to reach, and the ones that are not have to be read before that token can finish. A machine holding most of them waits rarely, one holding few waits often. We have not measured this across machine sizes and will not guess a figure: what we can say is that the model answers either way, and that the wait is the SSD's, not the model's.
Install
# upgrading? clear the previous version's unpack directory first
rm -rf ~/.libra/cache/onefile/gbx_lm
curl -fL -o gbx_lm-darwin-arm64.tar.gz 'https://github.com/GreenBitAI/gbx-lm/releases/latest/download/gbx_lm-darwin-arm64.tar.gz' \
&& tar -xzf gbx_lm-darwin-arm64.tar.gz gbx_lm \
&& mkdir -p "$HOME/.local/bin" \
&& mv gbx_lm "$HOME/.local/bin/gbx_lm" \
&& chmod +x "$HOME/.local/bin/gbx_lm"
gbx_lm -h
The build is signed with a Developer ID and notarised, so macOS runs it without the usual detour for a downloaded binary.
command not found -- $HOME/.local/bin is not on your PATH:
echo 'export PATH="$HOME/.local/bin:$PATH"' >> ~/.zshrc && source ~/.zshrc # zsh
echo 'export PATH="$HOME/.local/bin:$PATH"' >> ~/.bash_profile && source ~/.bash_profile # bash
Killed: 9 -- a previous version's files are still in the unpack directory,
and macOS refuses to mix two builds. Run the rm -rf line above, then try again.
Run
gbx_lm --model GreenBitAI/GLM-5.3-Flash-4bit-paged
That serves an OpenAI-compatible API on port 11688, which is its default. The
weights download on first use into ~/.libra/cache/models; set HF_HOME to put
them elsewhere, and HF_TOKEN if you meet the Hub's rate limits for anonymous
downloads.
curl http://127.0.0.1:11688/v1/chat/completions \
-H 'Content-Type: application/json' \
-d '{"model":"GreenBitAI/GLM-5.3-Flash-4bit-paged","messages":[{"role":"user","content":"Hello"}]}'
Where the weights fit they are filled from experts.bin and the model runs the
stock path at stock speed; where they do not, they stream from disk. Reading
the machine decides that, not a flag.
To override that: GBX_PAGING=off holds the experts resident.
Checked at build time, while the source checkpoint was still there to compare against:
- PASS layer-wise vs resident — 42 layers x 2 draws exact, 60.93 GiB peak for this gate
Quantization, tokenizer, chat template and licence are unchanged from pipenetwork/GLM-5.3-Flash-MLX-4bit.
From the command line
From gbx_lm v0.7.1, the binary also runs the model without a server -- one
prompt, or an interactive chat:
GBX_GLM53_MTP=on gbx_lm generate --model GreenBitAI/GLM-5.3-Flash-4bit-paged --prompt "Hello" --max-tokens 2048
GBX_GLM53_MTP=on gbx_lm chat --model GreenBitAI/GLM-5.3-Flash-4bit-paged --max-tokens 2048
gbx_lm generate -h and gbx_lm chat -h list their options. Keep
--max-tokens generous: the default is 100 for generate and 256 for chat,
and the model's reasoning before it answers counts against it. Leave out
GBX_GLM53_MTP=on to run without the draft head.
Coding agents
The server speaks three wire protocols on the same port, so the tools that expect a hosted API can be pointed at this one:
| path | for |
|---|---|
/v1/chat/completions | anything written against the OpenAI API |
/v1/responses | Codex |
/v1/messages | Claude Code |
Codex -- a provider in ~/.codex/config.toml:
[model_providers.gbx]
name = "gbx-lm"
base_url = "http://127.0.0.1:11688/v1"
wire_api = "responses"
and a profile in ~/.codex/gbx.config.toml:
model_provider = "gbx"
model = "GreenBitAI/GLM-5.3-Flash-4bit-paged"
model_context_window = 1048576
Claude Code -- ~/.claude/gbx.settings.json:
{
"env": {
"ANTHROPIC_BASE_URL": "http://127.0.0.1:11688",
"ANTHROPIC_AUTH_TOKEN": "local",
"ANTHROPIC_MODEL": "GreenBitAI/GLM-5.3-Flash-4bit-paged",
"ANTHROPIC_DEFAULT_HAIKU_MODEL": "GreenBitAI/GLM-5.3-Flash-4bit-paged"
}
}
Both clients ask for a small model for their own background work, so every name in the settings has to be one this server is serving.
The draft head
The mtp/ folder carries the model's own multi-token prediction head, converted
from zai-org/GLM-5.3-Flash, so speculative decoding works from this repository
alone. It is off unless asked for:
GBX_GLM53_MTP=on gbx_lm --model GreenBitAI/GLM-5.3-Flash-4bit-paged
Up to 1.4x, more as the context grows.
Measured 2026-10-13 with gbx_lm v0.8.0 on a 512 GB Mac Studio (M3 Ultra), weights
resident, greedy, thinking off, 256 tokens a reply, decode timed from the first token.
Short prompts: three each of code, prose and chat, three runs each, the median per kind.
Long contexts: a slice of source code and a question about it, the median of three runs.
| prompt | head off | head on | speedup |
|---|---|---|---|
| short, code | 39.5 tok/s | 55.5 | 1.41x |
| short, prose | 39.5 | 45.8 | 1.16x |
| short, chat | 39.5 | 50.8 | 1.29x |
| 3,400-token context | 32.6 | 40.0 | 1.23x |
| 14,000-token context | 32.2 | 43.8 | 1.36x |
| 29,000-token context | 31.4 | 42.5 | 1.35x |
Code gains most and prose least. With more context behind it the head proposes better -- it accepts about 63% of what it proposes on short prompts and 75-77% from 14k tokens on.
Every token the head proposes is checked by the model itself, so the reply is the model's own either way; the head only saves passes over the weights.