license: apache-2.0
language:
- en
pipeline_tag: text-generation
datasets:
- codeparrot/codeparrot-clean
- google-research-datasets/mbpp
tags:
- code
- python
- python-code
- code-generation
- code-completion
- causal-language-modeling
- decoder-only
- programming-language-model
- small-language-model
- from-scratch
- random-initialization
- custom-architecture
- custom-pytorch
- pytorch
- byte-level-bpe
- rope
- rmsnorm
- swiglu
- consumer-gpu
- rtx-3060
- research
- jumplander
- jl-code
JL-Code-Python-97M
A compact Python-focused causal language model trained from random initialization by JumpLander.
Overview
JL-Code-Python-97M is an experimental, Python-specialized decoder-only language model developed by JumpLander.
The checkpoint contains exactly 97,536,768 trainable parametersβapproximately 97.54 million parameters. It was trained from randomly initialized weights and does not inherit pretrained weights from Qwen, Llama, DeepSeek, Code Llama, GPT, or another external model family.
The release focuses on a narrow technical domain:
- Python source-code continuation
- Python function completion
- technical English associated with Python code
- docstring-to-code patterns
- short English-to-Python programming tasks
- fill-in-the-middle code reconstruction
This is a base research checkpoint, not a general chat model and not a production coding assistant.
Compatibility notice: this release uses a custom PyTorch architecture and a custom
.ptcheckpoint. It is not currently loadable throughAutoModelForCausalLM.from_pretrained(...). Use the includedjumplander_python_100m.pyfile for loading and inference.
JL-Code model family
JL-Code is JumpLander's language-specific code-model line. Each branch is intended to focus on one programming language rather than mixing every language into a single small checkpoint.
JumpLander
βββ JL-Code
βββ JL-Code-Python-97M β current release
βββ JL-Code-JavaScript-* β planned
βββ JL-Code-PHP-* β planned
βββ JL-Code-Rust-* β planned
βββ JL-Code-C-* β planned
βββ JL-Code-Cpp-* β planned
βββ JL-Code-SQL-* β planned
Planned names are directional and do not imply that those checkpoints have already been released.
At a glance
| Property | Value |
|---|---|
| Repository | jumplander/JL-Code-Python-97M |
| Developer | JumpLander |
| Model family | JL-Code |
| Release | v0.1-base |
| Status | Experimental research release |
| Primary domain | Python |
| Natural-language context | Technical English |
| Architecture | Custom decoder-only Transformer |
| Parameters | 97,536,768 |
| Initialization | Random initialization |
| External pretrained checkpoint | None |
| Context length | 1,024 tokens |
| Tokenizer | Custom Byte-Level BPE |
| Vocabulary | 16,384 tokens |
| Training objective | Causal language modeling |
| Framework | PyTorch |
| Training GPU | NVIDIA RTX 3060 12GB |
| Checkpoint format | Custom PyTorch training checkpoint (.pt) |
Architecture
The model architecture is implemented in jumplander_python_100m.py.
| Component | Configuration |
|---|---|
| Transformer blocks | 12 |
| Hidden dimension | 768 |
| Attention heads | 12 |
| Head dimension | 64 |
| Feed-forward dimension | 2,048 |
| Maximum sequence length | 1,024 |
| Vocabulary size | 16,384 |
| Position encoding | Rotary Position Embeddings (RoPE) |
| RoPE theta | 10,000 |
| Normalization | RMSNorm |
| RMSNorm epsilon | 1e-5 |
| MLP | SwiGLU |
| Attention | Causal self-attention |
| Attention implementation | PyTorch scaled dot-product attention |
| Attention/MLP bias | Disabled |
| Dropout | 0.0 |
| Input/output embedding tying | Enabled |
| Initialization standard deviation | 0.02 |
| Training gradient checkpointing | Enabled |
The exact machine-readable architecture is available in config.json.
Parameter count
97,536,768 trainable parameters
β 97.54M parameters
β 100M-class model
The repository name uses 97M to reflect the exact architecture more honestly than rounding it up to 100M.
Tokenizer
The tokenizer was trained specifically for this project from the prepared local training corpus.
| Property | Value |
|---|---|
| Algorithm | Byte-Level BPE |
| Vocabulary target | 16,384 |
| Minimum token frequency | 2 |
| Byte fallback | Enabled |
| Pre-tokenizer | ByteLevel |
| Decoder | ByteLevel |
Special tokens:
<pad>
<unk>
<bos>
<eos>
<file_start>
<file_end>
<fim_prefix>
<fim_suffix>
<fim_middle>
<instruction>
<response>
The tokenizer file required for inference is tokenizer.json.
Training data
The local data-building pipeline uses two public Hugging Face datasets.
1. CodeParrot Clean
- Dataset:
codeparrot/codeparrot-clean - Purpose: Python source-code pretraining and code-structure learning
- Source type: deduplicated Python files collected from public GitHub repositories
The upstream dataset includes per-file license metadata and contains code under multiple software licenses. Users should review the dataset card and original repository licenses before downstream commercial use.
2. MBPP
- Dataset:
google-research-datasets/mbpp - Alternate dataset card:
Muennighoff/mbpp - Purpose: short technical-English-to-Python examples and held-out programming tasks
- Content: natural-language tasks, Python reference solutions, and automated tests
MBPP examples assigned to test or validation splits were kept outside the main training split by the project pipeline.
Data preparation pipeline
The dataset was not passed directly into training. The local pipeline applied additional filtering and transformation:
- stream Python records from Hugging Face;
- normalize line endings and remove null bytes;
- reject very short or oversized files;
- detect likely credentials, keys, and private-key blocks;
- reject generated or minified files;
- validate Python using
ast.parse; - split large source files at Python function/class boundaries where possible;
- remove exact duplicates using SHA-256;
- create deterministic train, validation, and test splits;
- extract selected function/docstring pairs as English-to-Python instruction rows;
- add MBPP examples according to their upstream split;
- generate deterministic fill-in-the-middle variants for base training rows;
- tokenize and pack the corpus into contiguous
uint16token streams.
Prepared dataset statistics
| Statistic | Count |
|---|---|
| Accepted base samples | 20,000 |
| Final training rows | 35,855 |
| Final validation rows | 389 |
| Final test rows | 793 |
| Exact duplicates rejected | 391 |
| Generated files rejected | 246 |
| Secret-like samples rejected | 75 |
| Syntax-invalid samples rejected | 1,523 |
| Oversized samples rejected | 268 |
| Source records read | 10,809 |
A single accepted source file can produce more than one training rowβfor example, a base-code sample plus extracted function/docstring instruction samples. This is why the final training-row count is larger than the accepted-base-sample count.
Training configuration
The model was trained using next-token prediction over packed token sequences.
| Setting | Value |
|---|---|
| Optimizer | AdamW |
| Optimizer betas | (0.9, 0.95) |
| Optimizer epsilon | 1e-8 |
| Weight decay | 0.1 |
| Peak learning rate | 3e-4 |
| Minimum learning rate | 3e-5 |
| Scheduler | Cosine decay |
| Warmup | 200 optimizer steps |
| Total optimizer steps | 10,000 |
| Micro-batch size | 1 sequence |
| Gradient accumulation | 32 |
| Effective batch | 32 sequences |
| Sequence length | 1,024 tokens |
| Tokens per optimizer step | 32,768 |
| Approximate tokens processed | 327,680,000 |
| Gradient clipping | 1.0 |
| Evaluation interval | 250 steps |
| Checkpoint interval | 500 steps |
| Random seed | 1,337 |
| Precision | BF16 mixed precision |
| Hardware | NVIDIA RTX 3060 12GB |
Observed during training:
- approximately 8,400β9,000 tokens/second;
- approximately 1.86 GB peak allocated VRAM in the reported run;
- stable gradient norms during the observed training window.
The complete machine-readable run settings are in training_config.json.
Repository files
Recommended repository layout:
JL-Code-Python-97M/
βββ README.md
βββ config.json
βββ training_config.json
βββ jumplander_python_100m.pt
βββ tokenizer.json
βββ jumplander_python_100m.py
βββ requirements.txt
βββ DATA_SOURCES.md
| File | Purpose |
|---|---|
README.md |
Hugging Face model card |
config.json |
Machine-readable architecture description |
training_config.json |
Training and data-preparation settings |
jumplander_python_100m.pt |
Trained model checkpoint |
tokenizer.json |
Byte-Level BPE tokenizer |
jumplander_python_100m.py |
Model architecture, loading, generation, and web UI |
requirements.txt |
Python dependencies |
DATA_SOURCES.md |
Additional data provenance notes |
Do not upload .venv, __pycache__, Hugging Face caches, tokenized .bin training files, or private training logs unless they are intentionally part of the release.
Download
Hugging Face CLI
pip install -U huggingface_hub
hf download jumplander/JL-Code-Python-97M --local-dir JL-Code-Python-97M
cd JL-Code-Python-97M
Git and Git LFS
git lfs install
git clone https://huggingface.co/jumplander/JL-Code-Python-97M
cd JL-Code-Python-97M
Installation
python -m venv .venv
Windows PowerShell:
.\.venv\Scripts\Activate.ps1
Linux/macOS:
source .venv/bin/activate
Install dependencies:
pip install -r requirements.txt
Inspect the environment and local files:
python jumplander_python_100m.py check
Inspect the architecture and exact parameter count:
python jumplander_python_100m.py info
Inference
Terminal generation
Instruction-style prompt:
python jumplander_python_100m.py generate \
"Write a Python function that returns unique list items while preserving order."
Code completion:
python jumplander_python_100m.py generate \
"def fibonacci(n):" \
--mode completion \
--max-new-tokens 160 \
--temperature 0.2 \
--top-p 0.95
Windows PowerShell single-line example:
python jumplander_python_100m.py generate "Write a Python function that checks whether a number is prime."
Local browser UI
python jumplander_python_100m.py chat
Default address:
http://127.0.0.1:7860
The UI provides two modes:
- instruction-to-Python;
- Python code completion.
Checkpoint format
jumplander_python_100m.pt is a custom PyTorch training checkpoint containing:
model_name
model_config
train_config
model_state
optimizer_state
step
tokens_seen
saved_at
format_version
Because the checkpoint includes optimizer state, it can be larger than a weights-only release.
A future release should also provide:
- a weights-only checkpoint;
model.safetensors;- native Hugging Face Transformers integration;
AutoModelForCausalLMloading support.
Evaluation status
This release documents the completed training run, but it does not yet claim a verified HumanEval, MBPP pass@1, or production code-generation score.
Training loss alone does not establish code correctness. Proper evaluation should include:
- Python AST parse rate;
- executable completion rate;
- unit-test pass rate;
- MBPP pass@1 and pass@k;
- HumanEval evaluation after contamination review;
- repetition and memorization checks;
- security-oriented code review.
Until those evaluations are published, treat this checkpoint as an experimental base model.
Intended uses
Appropriate uses:
- research on small code language models;
- experiments with Python code completion;
- educational study of from-scratch Transformer training;
- tokenizer and data-pipeline research;
- local inference experiments;
- continued pretraining and instruction tuning;
- analysis of consumer-GPU model development.
Out-of-scope uses
This model is not intended for:
- production-critical code generation;
- security-sensitive implementation without review;
- autonomous deployment of generated code;
- legal, medical, financial, or safety-critical systems;
- generating or executing untrusted code without sandboxing;
- replacing human code review and automated testing.
Limitations
- The model is small and narrowly trained.
- It has limited general-world knowledge.
- It may generate invalid, incomplete, insecure, or fabricated Python code.
- English understanding is primarily tied to technical programming patterns.
- The context window is limited to 1,024 tokens.
- The training corpus is much smaller than corpora used for leading code models.
- GitHub-derived data can contain bugs, insecure patterns, biases, or licensing constraints.
- The current architecture is custom and is not yet integrated with Transformers.
- Generated code must be reviewed, sandboxed, and tested before use.
Safety and responsible use
Never execute generated code directly in a privileged environment.
Recommended controls:
- run generated code in a restricted sandbox;
- disable network access where possible;
- apply CPU, memory, and execution-time limits;
- scan generated code for secrets and unsafe operations;
- require unit tests and human review;
- avoid exposing private repositories or credentials to untrusted systems.
Licensing and data notice
The repository declares the Apache License 2.0 for JumpLander-authored code and released model artifacts.
That license declaration does not replace or override the licenses attached to upstream source files used by the training datasets. codeparrot/codeparrot-clean includes per-file license metadata from many public repositories. Users are responsible for reviewing the upstream dataset cards, source-code licenses, attribution requirements, and applicable law before commercial or regulated use.
MBPP is commonly distributed under CC BY 4.0; consult the current dataset card for attribution and reuse requirements.
This section is informational and is not legal advice.
Roadmap
Potential follow-up work:
- publish a weights-only
safetensorscheckpoint; - add Transformers-compatible configuration and model classes;
- publish reproducible evaluation scripts;
- evaluate on MBPP and HumanEval;
- expand high-quality Python training data;
- create a stronger instruction-tuned Python variant;
- train larger Python-specific models;
- extend the JL-Code family to additional programming languages.
Links
- Model: huggingface.co/jumplander/JL-Code-Python-97M
- JumpLander on Hugging Face: huggingface.co/jumplander
- JumpLander website: jumplander.org
- JumpLander documentation: jumplander.org/fa/docs
- CodeParrot Clean: huggingface.co/datasets/codeparrot/codeparrot-clean
- MBPP: huggingface.co/datasets/google-research-datasets/mbpp
Citation
@misc{jumplander_jl_code_python_97m_2026,
author = {{JumpLander}},
title = {JL-Code-Python-97M: A From-Scratch Python Code Language Model},
year = {2026},
publisher = {Hugging Face},
howpublished = {\url{https://huggingface.co/jumplander/JL-Code-Python-97M}},
note = {Experimental base release, version 0.1}
}
Acknowledgements
This project uses:
- PyTorch for model implementation and training;
- Hugging Face Datasets for dataset access;
- Hugging Face Tokenizers for Byte-Level BPE;
- CodeParrot Clean for Python source data;
- MBPP for English-to-Python programming tasks.
Built by JumpLander Β· Programming intelligence, code models, datasets, and developer systems