How to install libfyaml on Ubuntu?

Build from source using CMake or Autotools; install dependencies like llvm-dev for libclang support, then follow the build instructions in the README for a proper setup.

libfyaml vs yaml-cpp for C projects?

libfyaml is C-native with multi-layer APIs and typed serdes, while yaml-cpp is C++-focused. Choose libfyaml for C compatibility or reflection features; yaml-cpp for C++ ecosystems and simplicity.

How to use the reflection API to deserialize YAML into C structs?

Annotate your C headers, use fy_reflection_from_c_file_with_cflags to extract metadata, create a type context, and deserialize directly using the reflection API as shown in examples.

Does libfyaml support JSON parsing?

Yes, it fully supports JSON parsing and emission alongside YAML 1.2, making it versatile for both formats, with zero-copy operation in core paths.

Is libfyaml production ready?

No, it's in alpha (version 1.0-alpha4), so it's not recommended for production due to potential instability, breaking changes, and ongoing packaging fixes.

How to build libfyaml with CMake?

Create a build directory, run cmake .., then cmake --build ..; ensure optional dependencies like libclang-dev are installed if reflection authoring is needed.

libfyaml

MITCv0.9.6

A high-performance YAML 1.2 and JSON parser/emitter for C with zero-copy operation, generics, and reflection-based serdes.

GitHub

331 stars104 forks0 contributors

What is libfyaml?

libfyaml is a high-performance, feature-complete YAML 1.2 and JSON parser and emitter library written in C. It provides multiple API layers—core, generic, and reflection—for parsing, emitting, and manipulating structured data with zero-copy operation and full compliance with the YAML specification. It solves the problem of efficiently working with YAML and JSON in C applications, from low-level document control to high-level typed serialization.

Target Audience

C developers who need to parse, emit, or manipulate YAML or JSON data, particularly those working on configuration systems, data serialization, or tools requiring interoperability with YAML/JSON formats.

Value Proposition

Developers choose libfyaml for its comprehensive feature set, including zero-copy parsing, a Python-like generic API for flexible data handling, and reflection-based typed serdes for stable C structs. Its MIT license, full YAML 1.2 compliance, and multi-layer design make it a versatile and performant alternative to other YAML libraries.

Overview

Fully feature complete YAML parser and emitter, supporting the latest YAML spec and passing the full YAML testsuite.

Use Cases

Best For

Parsing and emitting YAML configuration files in C applications

Related Projects

Community-curated · Updated weekly · 100% open source

Found a gem we're missing?

Open-Awesome is built by the community, for the community. Submit a project, suggest an awesome list, or help improve the catalog on GitHub.

Submit a project Star on GitHub

Implementing typed serialization/deserialization between YAML and C structs

Building tools that require zero-copy YAML or JSON processing for performance

Prototyping data transformations in Python and porting them to C

Working with schema-less or schema-light YAML/JSON data in a Python-like manner

Developing cross-language applications that share YAML/JSON data models between C and Python

Not Ideal For

Projects requiring a stable, production-ready YAML library without the risks of alpha software
Applications that only need JSON parsing and don't benefit from YAML support or advanced features
Environments with minimal dependency tolerance, as reflection authoring requires optional libclang
Teams looking for a simple, single-API solution without the learning curve of multiple abstraction layers

Pros & Cons

Pros

Full YAML 1.2 Compliance

Passes the entire YAML test suite, ensuring reliable parsing and emission for configuration and data interchange tasks, as stated in the README.

Zero-Copy Performance

Core parsing paths use zero-copy operation, enhancing efficiency for large YAML and JSON documents, a key feature highlighted in the description.

Multi-Layer API Design

Offers core, generic, and reflection APIs, allowing developers to choose the right level of control or convenience, as emphasized in the philosophy section.

Python Interoperability

Includes a Python binding that mirrors the C generic API, enabling seamless prototyping and cross-language data modeling, demonstrated in the examples.

Typed Serialization Support

Reflection API provides direct serialization and deserialization between YAML and native C structs using type metadata, solving schema-driven workflows.

Cons

Alpha Release Status

As version 1.0-alpha4, it's not stable, with potential breaking changes and bugs, as evidenced by recent packaging fixes mentioned in the README.

Complex Build and Dependencies

Optional dependencies like libclang for reflection authoring, and documentation builds require Sphinx and LaTeX, adding setup overhead and complexity.

Steep Learning Curve

Three distinct API layers (core, generic, reflection) require developers to understand which to use, increasing initial effort and decision fatigue.

Limited Ecosystem

Being a newer project, it has fewer community resources, tutorials, and support compared to established libraries like yaml-cpp or libyaml.