| --- |
| license: other |
| language: [en] |
| tags: [midtraining, code, agentic, software-engineering, multi-agent] |
| task_categories: [text-generation] |
| --- |
| |
| # CooperData v3 — Midtraining Blend (Qwen3.5-9B cooperative SWE agents) |
|
|
| All-token **midtraining** mixture that bridges `Qwen/Qwen3.5-9B` (instruct) toward the cooperative |
| multi-agent SWE-coding SFT distribution. **One document per row** (`text`, tagged by `source`) — NOT |
| packed — so `trl.SFTTrainer(packing=False)` tokenizes per-doc and the Gated-DeltaNet recurrence |
| stays per-document. **~390M tokens.** |
|
|
| ## Composition |
| | source | tokens | share | role | |
| |---|---|---|---| |
| | `web` | 210.0M | 54% | general | |
| | `math` | 55.0M | 14% | general | |
| | `instruct` | 25.0M | 6% | general | |
| | `coop` | 60.0M | 15% | bridge | |
| | `swe_smith` | 15.0M | 4% | bridge | |
| | `nebius` | 15.0M | 4% | bridge | |
| | `social` | 10.0M | 3% | bridge | |
|
|
| General **~74%** / bridge **~26%** (coop-dominant). Agentic/social sources are rendered with |
| the model's **real** chat template (so coop tool-calls become native `<tool_call>`/`<tool_response>`, |
| matching the `qwen3_coder` serving parser). |
|
|
| ## Methodology |
| Grounded in ["Midtraining Bridges Pretraining and Posttraining Distributions" (2510.14865)](https://arxiv.org/abs/2510.14865): |
| specialized data is introduced *late* (a finished instruct model), so the conservative-weight finding |
| (high specialized weight late -> catastrophic forgetting) dictates a **general-dominant** mix. The |
| bridge is coop-dominant — near-domain agentic-coding on a coding model (low forgetting risk) and the |
| exact SFT target. Heavy agentic specialization is left to SFT. |
|
|
| ## Usage (all-token, packing=False) |
| ```python |
| from trl import SFTTrainer, SFTConfig |
| from datasets import load_dataset |
| ds = load_dataset("CooperBench/cooperdata-v3-midtrain-blend", split="train") |
| SFTTrainer(model="Qwen/Qwen3.5-9B", train_dataset=ds, |
| args=SFTConfig(dataset_text_field="text", packing=False, max_length=8192)) |
| ``` |
|
|
| ## Build |
| `coopertrain/train/modal/datamix/` (sources + mixture + cleaning). Inherits the licenses of its |
| constituent datasets (Dolmino, mini-coder-trajs, OdysSim) + our coop trajectories. |
|
|
