---
title: "cceval vs FastChat"
type: "comparison"
canonical_url: "https://www.graphcanon.com/compare/amazon-science-cceval-vs-lm-sys-fastchat"
tools: ["amazon-science-cceval", "lm-sys-fastchat"]
---

# cceval vs FastChat

*GraphCanon updated Jul 11, 2026*

## Verdict

Pick cceval when tags unique to cceval: python; pick FastChat when tags unique to FastChat: chatbots, distributed serving, evaluation system, large-language-models.

[cceval](https://crosscodeeval.github.io/) reports 181 GitHub stars, 25 forks, and 5 open issues, last pushed Aug 15, 2025. [FastChat](https://github.com/lm-sys/FastChat) has 39k stars, 4.8k forks, and 1.0k open issues, last pushed May 1, 2026. Figures are from public GitHub metadata via [cceval's repository](https://github.com/amazon-science/cceval) and [FastChat's repository](https://github.com/lm-sys/FastChat).

| | [cceval](/tools/amazon-science-cceval.md) | [FastChat](/tools/lm-sys-fastchat.md) |
| --- | --- | --- |
| Tagline | CrossCodeEval: A Diverse and Multilingual Benchmark for Cross-File Code Completion (NeurIPS 2023) | An open platform for training, serving, and evaluating large language models |
| Stars | 181 | 39,490 |
| Forks | 25 | 4,788 |
| Open issues | 5 | 1,027 |
| Language | Python | Python |
| Adopt for | - | FastChat is a comprehensive open platform for managing large language models (LLMs) that includes capabilities for training, serving, evaluating, and comparing chatbot models via web UIs and RESTful APIs. It powers ChatB |
| Persona | - | - |
| Runtime | - | - |
| License | Apache-2.0 | Apache-2.0 |
| Categories | Data & Retrieval, Evaluation & Observability | Evaluation & Observability, Inference & Serving, LLM Frameworks, Model Training |

## Trust and health

_Sourced signals - not a safety guarantee. No winner column._

| | [cceval](/tools/amazon-science-cceval.md) | [FastChat](/tools/lm-sys-fastchat.md) |
| --- | --- | --- |
| Maintenance | Slowing (36%) | Steady (60%) |
| Days since push | 330d | 71d |
| Open issues (now) | 5 | 1.0k |
| Security scan | 5 critical, 7 high, 8 medium, 21 low (5 critical, 7 high, 8 medium, 21 low) | No lockfile |
| Full report | [trust report](/tools/amazon-science-cceval/trust.md) | [trust report](/tools/lm-sys-fastchat/trust.md) |

## Shared compatibility

- **Python**: [cceval](/tools/amazon-science-cceval.md) - Python runtime; [FastChat](/tools/lm-sys-fastchat.md) - Python runtime

## Decision facts: FastChat

- **Adopt for:** FastChat is a comprehensive open platform for managing large language models (LLMs) that includes capabilities for training, serving, evaluating, and comparing chatbot models via web UIs and RESTful APIs. It powers ChatB

## Choose when

### Choose cceval if…

- Tags unique to cceval: python.
- Also covers Data & Retrieval.
- Leaner open-issue backlog (5).

### Choose FastChat if…

- Tags unique to FastChat: chatbots, distributed serving, evaluation system, large-language-models.
- Also covers Inference & Serving, LLM Frameworks, Model Training.
- - You are looking to train and evaluate state-of-the-art models such as Vicuna or MT-Bench.

## When NOT to use cceval

- Last GitHub push was 330 days ago (slowing maintenance, Aug 15, 2025). Validate activity before betting a new project on cceval.
- Data & Retrieval: Skip a heavy ingestion framework when your corpus is small and static; a script plus the embedding API is enough.
- Evaluation & Observability: Defer heavyweight eval infra only until you have real traffic - never skip it once users depend on answers.

## When NOT to use FastChat

- - You require a proprietary or closed-source framework; FastChat is open-source under Apache-2.0 license and its use might be unsuitable for environments requiring proprietary solutions.
- - Your chatbot evaluation needs do not align with the types of data used in FastChat's datasets (e.g., human votes, MT-Bench evaluations).
- - You prefer a more user-friendly setup without the need to clone a repository and manually install dependencies; FastChat requires installation from source with additional steps for Rust and CMake on
- + Mac.

## Common questions

### What is the difference between cceval and FastChat?

cceval: CrossCodeEval: A Diverse and Multilingual Benchmark for Cross-File Code Completion (NeurIPS 2023). FastChat: An open platform for training, serving, and evaluating large language models. See the comparison table for live GitHub stats and shared categories.

### When should I choose cceval over FastChat?

Choose cceval over FastChat when Tags unique to cceval: python; Also covers Data & Retrieval; Leaner open-issue backlog (5).

### When should I choose FastChat over cceval?

Choose FastChat over cceval when Tags unique to FastChat: chatbots, distributed serving, evaluation system, large-language-models; Also covers Inference & Serving, LLM Frameworks, Model Training; - You are looking to train and evaluate state-of-the-art models such as Vicuna or MT-Bench.

### When should I avoid cceval?

Last GitHub push was 330 days ago (slowing maintenance, Aug 15, 2025). Validate activity before betting a new project on cceval. Data & Retrieval: Skip a heavy ingestion framework when your corpus is small and static; a script plus the embedding API is enough. Evaluation & Observability: Defer heavyweight eval infra only until you have real traffic - never skip it once users depend on answers.

### When should I avoid FastChat?

- You require a proprietary or closed-source framework; FastChat is open-source under Apache-2.0 license and its use might be unsuitable for environments requiring proprietary solutions. - Your chatbot evaluation needs do not align with the types of data used in FastChat's datasets (e.g., human votes, MT-Bench evaluations). - You prefer a more user-friendly setup without the need to clone a repository and manually install dependencies; FastChat requires installation from source with additional steps for Rust and CMake on + Mac.

### Is cceval or FastChat more popular on GitHub?

FastChat has more GitHub stars (39,490 vs 181). Stars measure visibility, not whether either tool fits your constraints.

### Are cceval and FastChat open source?

Yes - both are open-source projects on GitHub (cceval: Apache-2.0, FastChat: Apache-2.0).

### Where can I find alternatives to cceval or FastChat?

GraphCanon lists graph-backed alternatives at [cceval alternatives](/tools/amazon-science-cceval/alternatives) and [FastChat alternatives](/tools/lm-sys-fastchat/alternatives) ([cceval markdown twin](/tools/amazon-science-cceval/alternatives.md), [FastChat markdown twin](/tools/lm-sys-fastchat/alternatives.md)), ranked by typed relationship edges rather than popularity votes.

### Is there a machine-readable version of this comparison?

Yes. The markdown twin at [this comparison](/compare/amazon-science-cceval-vs-lm-sys-fastchat.md) mirrors this page for agents and LLM crawlers, with the same stats table and FAQ answers.

### Which is better maintained, cceval or FastChat?

cceval: Slowing. FastChat: Steady. Compare maintenance labels, days since push, and release cadence in the trust section below - stars alone do not measure maintenance.

### Where are the full trust reports for cceval and FastChat?

GraphCanon publishes per-repo trust reports with dated maintenance, provenance, and scan summaries: [cceval trust report](/tools/amazon-science-cceval/trust); [FastChat trust report](/tools/lm-sys-fastchat/trust).

---

**Machine-readable endpoints**

- JSON: [`/api/graphcanon/graph?tool=amazon-science-cceval`](/api/graphcanon/graph?tool=amazon-science-cceval)
- LLM index: [/llms.txt](/llms.txt)
- Full corpus: [/llms-full.txt](/llms-full.txt)

_GraphCanon - The knowledge graph for AI development. https://www.graphcanon.com/_
