SIEVE

A parameterized GitHub corpus builder for contamination-free, post-cutoff code evaluation.

SIEVE (Software Ingestion & Extraction for Verifiable Evaluation) is a parameterized GitHub corpus builder for software engineering research.

The Problem

Evaluating LLMs on code tasks is increasingly compromised by training data contamination—benchmarks built from public repositories risk overlapping with a model’s training set, inflating reported performance.

Our Approach

SIEVE produces contamination-free, post-cutoff code corpora directly from public repositories, with full control over language, recency, and repository quality. It supports Python, Java, JavaScript, and C++, and includes a CodeBERT-based classifier for detecting LLM-generated code (F1=0.9478, AUROC=0.9902, trained on 114K samples across 9 LLMs).

Stack

Python, Streamlit, HuggingFace, tree-sitter


View the code on GitHub. Try the live demo on HuggingFace Spaces. Paper to appear at MSR 2027 (Data & Tool Showcase Track).