| --- |
| language: |
| - en |
| - zh |
| - es |
| - ur |
| license: apache-2.0 |
| task_categories: |
| - text-generation |
| tags: |
| - code |
| - multilingual |
| - legesher |
| - transpilation |
| - tiny-aya-expedition |
| - language-decoded |
| pretty_name: Language Decoded Data |
| size_categories: |
| - 100K<n<1M |
| configs: |
| - config_name: condition-1-en-32k |
| data_files: |
| - split: train |
| path: data/condition-1-en-32k/train-* |
| - split: validation |
| path: data/condition-1-en-32k/validation-* |
| - config_name: condition-1-en-5k |
| data_files: |
| - split: train |
| path: data/condition-1-en-5k/train-* |
| - split: validation |
| path: data/condition-1-en-5k/validation-* |
| - config_name: condition-2-es-32k |
| data_files: |
| - split: train |
| path: data/condition-2-es-32k/train-* |
| - split: validation |
| path: data/condition-2-es-32k/validation-* |
| - config_name: condition-2-es-5k |
| data_files: |
| - split: train |
| path: data/condition-2-es-5k/train-* |
| - split: validation |
| path: data/condition-2-es-5k/validation-* |
| - config_name: condition-2-ur-32k |
| data_files: |
| - split: train |
| path: data/condition-2-ur-32k/train-* |
| - split: validation |
| path: data/condition-2-ur-32k/validation-* |
| - config_name: condition-2-ur-5k |
| data_files: |
| - split: train |
| path: data/condition-2-ur-5k/train-* |
| - split: validation |
| path: data/condition-2-ur-5k/validation-* |
| - config_name: condition-2-zh-32k |
| data_files: |
| - split: train |
| path: data/condition-2-zh-32k/train-* |
| - split: validation |
| path: data/condition-2-zh-32k/validation-* |
| - config_name: condition-2-zh-5k |
| data_files: |
| - split: train |
| path: data/condition-2-zh-5k/train-* |
| - split: validation |
| path: data/condition-2-zh-5k/validation-* |
| - config_name: condition-3-zh-5k |
| data_files: |
| - split: train |
| path: data/condition-3-zh-5k/train-* |
| - split: validation |
| path: data/condition-3-zh-5k/validation-* |
| - config_name: condition-4-zh-5k |
| data_files: |
| - split: train |
| path: data/condition-4-zh-5k/train-* |
| - split: validation |
| path: data/condition-4-zh-5k/validation-* |
| dataset_info: |
| - config_name: condition-1-en-32k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 403718262 |
| num_examples: 31818 |
| - name: validation |
| num_bytes: 42626910 |
| num_examples: 3536 |
| download_size: 164619518 |
| dataset_size: 446345172 |
| - config_name: condition-1-en-5k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 55261555 |
| num_examples: 4500 |
| - name: validation |
| num_bytes: 6365959 |
| num_examples: 500 |
| download_size: 22897728 |
| dataset_size: 61627514 |
| - config_name: condition-2-es-32k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 408041994 |
| num_examples: 31818 |
| - name: validation |
| num_bytes: 43090956 |
| num_examples: 3536 |
| download_size: 166000000 |
| dataset_size: 451132950 |
| - config_name: condition-2-es-5k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 55864731 |
| num_examples: 4500 |
| - name: validation |
| num_bytes: 6432095 |
| num_examples: 500 |
| download_size: 23031674 |
| dataset_size: 62296826 |
| - config_name: condition-2-ur-32k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 415552907 |
| num_examples: 31818 |
| - name: validation |
| num_bytes: 43879443 |
| num_examples: 3536 |
| download_size: 166000000 |
| dataset_size: 459432350 |
| - config_name: condition-2-ur-5k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 56906247 |
| num_examples: 4500 |
| - name: validation |
| num_bytes: 6545730 |
| num_examples: 500 |
| download_size: 23158039 |
| dataset_size: 63451977 |
| - config_name: condition-2-zh-32k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 405515831 |
| num_examples: 31818 |
| - name: validation |
| num_bytes: 45065811 |
| num_examples: 3536 |
| download_size: 165387142 |
| dataset_size: 450581642 |
| - config_name: condition-2-zh-5k |
| features: |
| - name: file_path |
| dtype: string |
| - name: code |
| dtype: string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: string |
| - name: license |
| dtype: string |
| - name: token_count |
| dtype: int32 |
| splits: |
| - name: train |
| num_bytes: 55793642 |
| num_examples: 4500 |
| - name: validation |
| num_bytes: 6422792 |
| num_examples: 500 |
| download_size: 22978834 |
| dataset_size: 62216434 |
| - config_name: condition-3-zh-5k |
| features: |
| - name: file_path |
| dtype: large_string |
| - name: code |
| dtype: large_string |
| - name: code_en |
| dtype: string |
| - name: language |
| dtype: large_string |
| - name: license |
| dtype: large_string |
| - name: token_count |
| dtype: int64 |
| - name: source_type |
| dtype: large_string |
| splits: |
| - name: train |
| num_bytes: 40782466 |
| num_examples: 4500 |
| - name: validation |
| num_bytes: 4531385 |
| num_examples: 500 |
| download_size: 17299185 |
| dataset_size: 45313851 |
| - config_name: condition-4-zh-5k |
| features: |
| - name: filename |
| dtype: string |
| - name: content |
| dtype: string |
| - name: extension |
| dtype: string |
| - name: source |
| dtype: string |
| - name: quality_tier |
| dtype: string |
| - name: sha256 |
| dtype: string |
| - name: byte_size |
| dtype: int64 |
| - name: total_lines |
| dtype: int64 |
| - name: cjk_ratio |
| dtype: float64 |
| - name: has_cjk |
| dtype: bool |
| splits: |
| - name: train |
| num_bytes: 44246508 |
| num_examples: 6553 |
| - name: validation |
| num_bytes: 7522476 |
| num_examples: 729 |
| download_size: 18300000 |
| dataset_size: 51768984 |
| --- |
| |
| # Language Decoded | Multilingual Code Dataset |
|
|
| Multilingual Python code datasets for the **Language Decoded** project (part of [Cohere's Tiny Aya Expedition](https://aya.for.ai)), investigating whether code's reasoning benefit for language models is **language-dependent** or **structure-dependent**. |
|
|
| ## Research Question |
|
|
| > Does fine-tuning on non-English code (Python with translated keywords) improve multilingual reasoning as much as English code does? |
|
|
| Prior work ([Aryabumi et al., 2024 -- "To Code or Not to Code"](https://arxiv.org/abs/2408.10914)) demonstrated that including English code in pre-training data improves downstream reasoning performance by approximately 8%. However, that study only tested English code. This dataset enables the natural follow-up: does the reasoning benefit come from the _structure_ of code, or from the _language_ of its keywords? |
|
|
| ## Dataset Description |
|
|
| This dataset provides filtered, quality-controlled Python source code in multiple configurations: the original English, three keyword-swapped variants (Chinese, Spanish, Urdu), a blended native+transpiled mix, and strictly native Chinese code. The source data is drawn from [bigcode/the-stack-dedup](https://huggingface.co/datasets/bigcode/the-stack-dedup) (Python subset), filtered for quality using the following criteria: |
|
|
| - AST-valid Python only (must parse without errors) |
| - Permissive licenses only (MIT, Apache-2.0, BSD, etc.) |
| - 10--1000 lines of code |
| - Minimum 21 GitHub stars |
| - No autogenerated files |
| - SHA-256 deduplication |
|
|
| Keyword-swapped variants are produced using [Legesher](https://github.com/legesher/legesher) v0.7.3, which translates Python reserved words (37 keywords, 72 builtins, 66 exceptions) into the target language while preserving code structure and semantics. |
|
|
| ## Available Configs |
|
|
| Each condition is available in two sizes: `-32k` (full filtered corpus, ~31.8k train + ~3.5k validation) and `-5k` (stratified subset, 4.5k train + 500 validation). The `-5k` subsets are used for QLoRA fine-tuning on consumer GPUs. |
|
|
| | Config | Condition | Language | Description | Train | Val | |
| | -------------------- | ----------- | -------- | ------------------------------------------------------------ | ------ | ----- | |
| | `condition-1-en-32k` | 1 (control) | English | Unmodified filtered Python from The Stack Dedup | 31,818 | 3,536 | |
| | `condition-1-en-5k` | 1 (control) | English | Stratified 5k subset of condition-1 | 4,500 | 500 | |
| | `condition-2-zh-32k` | 2 | Chinese | Keyword-swapped Python via Legesher v0.7.3 | 31,818 | 3,536 | |
| | `condition-2-zh-5k` | 2 | Chinese | Stratified 5k subset of condition-2-zh | 4,500 | 500 | |
| | `condition-2-es-32k` | 2 | Spanish | Keyword-swapped Python via Legesher v0.7.3 | 31,818 | 3,536 | |
| | `condition-2-es-5k` | 2 | Spanish | Stratified 5k subset of condition-2-es | 4,500 | 500 | |
| | `condition-2-ur-32k` | 2 | Urdu | Keyword-swapped Python via Legesher v0.7.3 | 31,818 | 3,536 | |
| | `condition-2-ur-5k` | 2 | Urdu | Stratified 5k subset of condition-2-ur | 4,500 | 500 | |
| | `condition-3-zh-5k` | 3 | Chinese | Blended: 3,486 native Chinese code + 1,514 transpiled Python | 4,500 | 500 | |
| | `condition-4-zh-5k` | 4 | Chinese | Strictly native Chinese code (no transpiled code) | 6,553 | 729 | |
|
|
| ## Schema |
|
|
| ### Conditions 1--2 |
|
|
| Used by: `condition-1-en-*`, `condition-2-zh-*`, `condition-2-es-*`, `condition-2-ur-*` |
|
|
| | Column | Type | Description | |
| | ------------- | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------- | |
| | `code` | string | Python source code. For condition-2 configs, this is the transpiled (keyword-swapped) version. For condition-1, this is the original English source. | |
| | `code_en` | string | Original English Python source code. Identical to `code` for condition-1-en. | |
| | `language` | string | ISO 639-1 language code: `en`, `ur`, `zh`, or `es`. | |
| | `file_path` | string | Original file path in The Stack Dedup. | |
| | `license` | string | SPDX license identifier for the source file. | |
| | `token_count` | int64 | Token count computed using the CohereLabs/tiny-aya-base tokenizer. | |
|
|
| ### Condition 3 |
|
|
| Used by: `condition-3-zh-5k` |
|
|
| Condition 3 blends native Chinese code with transpiled code and adds a `source_type` column to distinguish them. `code_en` is populated for transpiled rows (keeping them in sync with conditions 1--2) but null for native code rows, which have no English equivalent. |
|
|
| | Column | Type | Description | |
| | ------------- | ----------- | ---------------------------------------------------------------------------------- | |
| | `file_path` | string | File identifier (native filename or transpiled file path) | |
| | `code` | string | The code content (native or transpiled) | |
| | `code_en` | string/null | English original -- populated for transpiled rows, null for native code rows | |
| | `language` | string | ISO 639-1 language code (`zh`) | |
| | `license` | string | Source license (SPDX identifier, `UNKNOWN`, or `varies`) | |
| | `token_count` | int64 | Token count computed using the CohereLabs/tiny-aya-base tokenizer | |
| | `source_type` | string | `"native"` (natively Chinese-authored) or `"transpiled"` (keyword-swapped English) | |
|
|
| ### Condition 4 |
|
|
| Used by: `condition-4-zh-5k` |
|
|
| Condition 4 contains strictly native Chinese code -- code written by developers who think and code in Chinese. This uses the same schema as the [language-decoded-community](https://huggingface.co/datasets/legesher/language-decoded-community) dataset rather than the transpilation schema, since there is no English original to reference. |
|
|
| | Column | Type | Description | |
| | -------------- | ------- | -------------------------------------------------------------- | |
| | `filename` | string | Original filename | |
| | `content` | string | The code content | |
| | `extension` | string | File extension (e.g., `.py`, `.c`, `.wenyan`) | |
| | `source` | string | Data source (e.g., `thestack`, `wenyan`, `program_in_chinese`) | |
| | `quality_tier` | string | Quality rating: `A` (highest) through `D` (lowest) | |
| | `sha256` | string | SHA-256 hash for deduplication | |
| | `byte_size` | int64 | File size in bytes | |
| | `total_lines` | int64 | Total line count | |
| | `cjk_ratio` | float64 | Ratio of CJK characters in the file | |
| | `has_cjk` | bool | Whether the file contains CJK characters | |
|
|
| ## Experimental Conditions |
|
|
| The Language Decoded experiment uses a ladder of conditions to isolate the mechanism behind code's reasoning benefit: |
|
|
| | Condition | Name | Purpose | |
| | ----------- | -------------------- | ----------------------------------------------------------------------------------------- | |
| | Baseline | No fine-tuning | Establishes the performance floor | |
| | Condition 1 | English code | Tests whether code fine-tuning helps at all (replicates Aryabumi et al.) | |
| | Condition 2 | Keyword-swapped code | Tests whether the _language_ of keywords matters for the reasoning benefit | |
| | Condition 3 | Mixed native sources | Tests whether diverse native-language code adds value beyond keyword swapping | |
| | Condition 4 | Strictly native code | Tests whether code authored by native speakers carries unique signal beyond transpilation | |
|
|
| ### The Experimental Ladder |
|
|
| - **Baseline --> 1**: Does code help at all? |
| - **1 --> 2**: Does the language of keywords matter? |
| - **2 --> 3**: Does diversity of native-language sources add value beyond keyword swap? |
| - **3 --> 4**: Does code written in the cultural context of a language carry something that transpiled+mixed can't? |
|
|
| ## Usage |
|
|
| ```python |
| from datasets import load_dataset |
| |
| # Load full-size English code (control) |
| ds = load_dataset("legesher/language-decoded-data", "condition-1-en-32k") |
| |
| # Load 5k subset (for QLoRA fine-tuning) |
| ds = load_dataset("legesher/language-decoded-data", "condition-1-en-5k") |
| |
| # Load keyword-swapped variants |
| ds = load_dataset("legesher/language-decoded-data", "condition-2-zh-5k") |
| ds = load_dataset("legesher/language-decoded-data", "condition-2-es-5k") |
| ds = load_dataset("legesher/language-decoded-data", "condition-2-ur-5k") |
| |
| # Load blended native + transpiled (condition 3) |
| ds = load_dataset("legesher/language-decoded-data", "condition-3-zh-5k") |
| |
| # Load strictly native code (condition 4) |
| ds = load_dataset("legesher/language-decoded-data", "condition-4-zh-5k") |
| |
| # Access splits |
| train = ds["train"] |
| val = ds["validation"] |
| |
| # Filter condition-3 by source type |
| native_only = train.filter(lambda x: x["source_type"] == "native") |
| ``` |
|
|
| ## Technical Details |
|
|
| | Parameter | Value | |
| | ---------------------- | ------------------------------------------------------------------------------------------------------------------ | |
| | Source dataset | [bigcode/the-stack-dedup](https://huggingface.co/datasets/bigcode/the-stack-dedup) (Python subset) | |
| | Transpilation tool | [Legesher](https://github.com/legesher/legesher) v0.7.3 (legesher-core, legesher-i18n) | |
| | Tokenizer | CohereLabs/tiny-aya-base | |
| | Base model | [CohereLabs/tiny-aya-base](https://huggingface.co/CohereLabs/tiny-aya-base) (3.35B params) | |
| | Train/validation split | 90% / 10% (seed 42) | |
| | File format | Parquet (snappy compression) | |
| | Filtering criteria | AST-valid, permissive licenses, 10--1000 lines, min 21 GitHub stars, no autogenerated files, SHA-256 deduplication | |
|
|
| ## Limitations |
|
|
| - **Source bias**: The Stack Dedup skews toward popular, well-starred GitHub repositories, which may not represent the full diversity of Python code in the wild. |
| - **Keyword-only transpilation**: Legesher translates Python reserved words (keywords, builtins, exceptions) but leaves comments, docstrings, string literals, and variable/function names in their original language (typically English). This means condition-2 code is a hybrid of translated keywords and English identifiers. |
| - **Token count variation**: Transpiled code may have different token counts than the English original due to multi-byte characters (especially for Chinese and Urdu), even though the code structure is identical. |
| - **Single programming language**: Currently limited to Python. Results may not generalize to other programming languages. |
| - **Condition 4 scope**: Native Chinese code is limited to publicly available sources (The Stack, Wenyan, Program-in-Chinese, Qi, Mulan) and may not represent the full spectrum of Chinese-language programming. |
|
|
| ## Citation |
|
|
| ```bibtex |
| @misc{language-decoded-2026, |
| title={Language Decoded: Investigating Language-Dependent vs. Structure-Dependent Reasoning Benefits of Code}, |
| author={Madison Edgar and Saad Ahmed Bazaz and Tom Sherborne and Rashik Shahjahan and Khojasteh Mirza and Sarah Jawaid and Rafay Mustafa and Sohaib Ahmed Bazaz}, |
| year={2026}, |
| publisher={Hugging Face}, |
| url={https://huggingface.co/datasets/legesher/language-decoded-data} |
| } |
| ``` |
|
|
| ## Links |
|
|
| - [Legesher on GitHub](https://github.com/legesher/legesher) |
| - [Tiny Aya Expedition](https://aya.for.ai) |
| - [bigcode/the-stack-dedup](https://huggingface.co/datasets/bigcode/the-stack-dedup) |
| - [Language Decoded Community (native code)](https://huggingface.co/datasets/legesher/language-decoded-community) |
| - [Language Decoded Experiments (tracking)](https://huggingface.co/datasets/legesher/language-decoded-experiments) |
| - [Language Decoded LoRA (model hub)](https://huggingface.co/legesher/language-decoded-lora) |
|
|
| ## License |
|
|
| Apache 2.0 |
|
|