ScaleBox: A High-Fidelity and Scalable Code Verification System for Large Language Models

ScaleBox is an open-source project developed by the team from the Institute of Information Engineering, Chinese Academy of Sciences (IIE CAS). It was selected as an ACL 2026 demo paper. This project focuses on solving the verification challenges of code generated by large language models, providing a high-fidelity and scalable code verification solution, aiming to offer more reliable infrastructure for the objective evaluation of LLM code generation capabilities.

With the widespread application of large language models in the field of code generation, how to efficiently and accurately verify the correctness of generated code has become a key issue. Current mainstream evaluation benchmarks (such as HumanEval, MBPP) have obvious limitations in terms of verification fidelity and scalability. The ScaleBox project was born in this context, with the core goal of building a system that combines high-fidelity verification results and large-scale scalability.

Existing code verification solutions face four major challenges:

1. Insufficient Verification Fidelity: Misjudgment issues (false positives/negatives) affect the credibility of evaluations;
2. Scalability Bottlenecks: Traditional architectures struggle to scale linearly while maintaining high accuracy;
3. Environmental Consistency Issues: Differences in runtime environments lead to irreproducible results;
4. Limited Test Case Coverage: Existing benchmarks struggle to cover edge cases, easily misjudging defective code.

ScaleBox addresses challenges through multiple technical innovations:

• Containerized Execution Environment: Uses Docker to build isolated, standardized environments, ensuring consistency and security;
• Multi-level Verification Strategy: Combines static analysis, syntax checking, runtime monitoring, and other multi-dimensional evaluations;
• Intelligent Test Generation: Automatically generates test cases for boundary conditions and abnormal paths to improve coverage comprehensiveness;
• Distributed Verification Architecture: Supports parallel execution of tasks to achieve horizontal scalability;
• Result Consistency Guarantee: Multiple execution comparisons, cross-environment verification, and detailed logs facilitate auditing.

ScaleBox's application scenarios include:

1. Model R&D Evaluation: Helps teams accurately understand the real capabilities of models and identify improvement directions;
2. Model Comparison Evaluation: Ensures fair and credible comparison results between different models (e.g., GPT-4, Claude, CodeLlama);
3. Production Code Screening: Provides automated quality control for enterprises to screen code usable in production;
4. Benchmark Improvement: Helps maintainers identify and fix issues in existing test sets.

Technical highlights:

• Modular Design: Clear component responsibilities, easy to maintain and extend;
• Configuration-Driven: Flexibly define verification processes via configuration files;
• Detailed Analysis Reports: Outputs in-depth information such as execution time, coverage rate, error classification, etc.;
• API-Friendly: Provides Python API for easy integration. Comparison with existing tools:
• Higher fidelity than benchmark scripts like HumanEval;
• Provides a more complete verification pipeline than simple sandboxes;
• Open-source nature gives users full control, suitable for academic and customized scenarios.

Usage suggestions:

1. Ensure Docker environment is correctly configured (core mechanism);
2. Start with sample configurations, adjust gradually, and verify effects on small-scale samples;
3. Prepare input data that meets format requirements (e.g., JSON/JSONL format);
4. Make full use of detailed reports to analyze error distribution, coverage rate, and other information to reveal model shortcomings.

Research Significance: ScaleBox promotes the development of the code evaluation field towards high fidelity and scalability. Future Outlook:

• Support more complex scenarios (multi-file projects, cross-language calls);
• Introduce semantic verification (focus on code quality, readability, security);
• Dynamic difficulty adjustment and integration of human feedback. Summary: ScaleBox effectively addresses the limitations of existing tools, provides reliable infrastructure for model evaluation and AI code applications, and is expected to become an important open-source tool in the code verification field.