Hardware tiers
What to serve based on your Mac's unified memory. These
four picks are what install.sh ships as its RAM
recommender — one canonical alias per tier, boot-verified against
rapid-mlx 0.10.3 on M3 Ultra.
RECOMMENDED_MODEL block in
install.sh
writes into the quick-start banner after
curl -fsSL https://rapidmlx.com/install.sh | bash.
Boot times and peak RSS come from
PR #1053's
cached-model empirical run (M3 Ultra 256 GB, port 8804-8807,
/v1/models-Ready gate).
The RAM → alias map
| RAM tier | Alias (default recommendation) | HF repo | Boot to /v1/models |
Peak RSS |
|---|---|---|---|---|
| 96+ GB | gpt-oss-120b-mxfp4-q8 |
mlx-community/gpt-oss-120b-MXFP4-Q8 |
15 s | 60.9 GB |
| 48-95 GB | qwen3.6-35b-8bit |
mlx-community/Qwen3.6-35B-A3B-8bit |
11 s | 35.6 GB |
| 24-47 GB | gpt-oss-20b-mxfp4-q8 |
mlx-community/gpt-oss-20b-MXFP4-Q8 |
6 s | 12.1 GB |
| 8-23 GB | qwen3.5-4b-4bit |
mlx-community/Qwen3.5-4B-MLX-4bit |
8 s | 2.8 GB |
96+ GB · Mac Studio / Pro
Pick: gpt-oss-120b-mxfp4-q8
· rapid-mlx serve gpt-oss-120b-mxfp4-q8
OpenAI's harmony-native 120B MoE at MXFP4 with 8-bit accumulators.
Native harmony reasoning + tool calling, so
--tool-call-parser harmony is auto-selected. Cache
footprint on disk is roughly 59 GB — comfortably below the M3 Ultra
256 GB envelope with headroom for a second sidecar model.
Rationale: at this tier the picky question is "frontier reasoning + tool calling on-device". 120B-MXFP4 is the largest checkpoint that boots in seconds and fits below the 96 GB working-set floor, so it wins the tier over 122B dense / 158B DeepSeek V4 Flash both of which spill past the 96 GB envelope on typical prompts.
48-95 GB · Mac Studio
Pick: qwen3.6-35b-8bit
· rapid-mlx serve qwen3.6-35b-8bit
Qwen 3.6 35B-A3B (35B total / 3B active MoE) in 8-bit MLX. Ships with
a native MTP head baked into every checkpoint, so
--enable-mtp (or a
--speculative-config '{"method":"mtp"}') accelerates
decode without a separate drafter download. The
hermes / qwen3 parser pair is auto-selected.
Rationale: the 35B-A3B sweet spot — active-parameter cost of a 3B model, quality of a 35B — anchors this tier. 8-bit MLX at ~35 GB peak RSS leaves 13-60 GB free at 48-95 GB budgets for prefix cache and concurrent sequences.
24-47 GB · Mac Mini / Studio
Pick: gpt-oss-20b-mxfp4-q8
· rapid-mlx serve gpt-oss-20b-mxfp4-q8
The smaller sibling of the 96+ pick. Harmony-native, ~11 GB on disk, 12.1 GB peak RSS during a warm boot. Fits comfortably at 24 GB with a normal browser + IDE workload alongside.
Rationale: at 24-47 GB the ceiling is set by the "leave room for VS Code + Chrome + a build" reality. A ~12 GB peak-RSS harmony-native model that responds at real chat speed on M-series is the honest highest quality that clears this bar.
8-23 GB · MacBook Air / small mini
Pick: qwen3.5-4b-4bit
· rapid-mlx serve qwen3.5-4b-4bit
Qwen 3.5 4B at 4-bit MLX. Runs fine on a 16 GB MacBook Air with power
to spare. Also the default alias for
rapid-mlx chat,
rapid-mlx launch,
and the matrix cheap-alias policy.
Why not Qwen 3.6 here? Qwen 3.6 has no <8B SKU at time of release, so the recommender falls back to 3.5-4B. When 3.6 ships a small variant, the install.sh map will be re-verified for this tier.
Verify empirically
The installer's doctor subcommand reports your machine's
Apple Silicon variant, macOS version, free disk, and HF cache size,
then flags any missing optional extras.
$ rapid-mlx doctor
Sample output on M3 Ultra 256 GB:
◆ System ✓ Apple Silicon (Apple M3 Ultra, 256 GB) ✓ macOS 26.5.1 (Darwin 25.5.0) ✓ Free disk: 114 GB ◆ Required Packages ✓ mlx 0.32.0 ✓ mlx-lm 0.31.3 ✓ rapid-mlx 0.10.3