locailabs/nemotron-chat-welsh

---
language:
- cy
- en
license: cc-by-4.0
task_categories:
- text-generation
tags:
- welsh
- cymraeg
- nemotron
- synthetic
- translation
- sft
---

# Nemotron Instruction Following Chat — Welsh (Cymraeg)

Welsh-language supervised fine-tuning dataset translated from the NVIDIA Nemotron
Instruction Following Chat dataset using an LLM translation pipeline.

## Dataset summary

| Split | Count | Description |
|-------|-------|-------------|
| `train` | 27807 | Welsh translations of English chat instruction-following examples |

## How this dataset was made

### 1. Source data

Examples were drawn from `nvidia/Nemotron-Instruction-Following-Chat-v1`
(`chat_if` split, filtered to `capability_target == chat`), yielding 336,831
candidate rows.

### 2. Preprocessing

Each row was preprocessed as follows:

1. **Conversation flattening** — multi-turn messages stripped of system prompts
and truncated to the first user–assistant turn, producing `{prompt, response}`
pairs.
2. **Content filtering** — rows containing model self-identification strings
(e.g. "nemotron") removed (64,157 rows filtered).
3. **Language detection** — rows where either the prompt or response was detected
as non-English were removed using `lingua-language-detector` (12,924 rows
filtered), leaving **259,750 rows**.

### 3. Translation

Each prompt and response was independently translated from English to Welsh using
`qwen/qwen3.5-35b-a3b` via OpenRouter (non-thinking/instruct mode). The pipeline
uses async calls (50 concurrent) with per-row retry logic and incremental JSONL
output for resume support.

Translation prompt instructs the model to preserve XML tags, URLs, mathematical
formulas, and code blocks verbatim.

### 4. Format

Each row contains a `messages` list in standard chat format:

```json
{
"messages": [
{"role": "user", "content": "..."},
{"role": "assistant", "content": "..."}
]
}
```

## Intended use

Post-training / fine-tuning LLMs to add Welsh language capability.

## Source dataset

`nvidia/Nemotron-Instruction-Following-Chat-v1`