Chrono (crate)

Chrono (crate)
Name	Chrono
Language	Rust
License	MIT OR Apache-2.0
Repository	crates.io
Latest release	stable
Genre	library

Chrono (crate) Chrono is a Rust library for date and time handling, providing parsing, formatting, timezone conversion, and arithmetic utilities used across systems and applications. It integrates with ecosystems and tools such as Rust, Cargo (software), LLVM, Mozilla, Microsoft, and Amazon (company), serving projects in domains associated with Linux, Windows, macOS, Android (operating system), and iOS. Chrono has been adopted in software that interoperates with standards and platforms like POSIX, ISO 8601, NTP, UNIX time, and services from Google, Facebook, Twitter, GitHub, and GitLab.

Overview

Chrono provides a strongly typed API for temporal values, offering types for naive dates, times, combined datetime, durations, and timezone-aware instants used in applications ranging from web backends like Actix (web framework), Rocket (web framework), and Warp (web server), to databases such as PostgreSQL, MySQL, and SQLite. The crate interoperates with serialization formats and libraries including Serde (framework), JSON, Protocol Buffers, MessagePack, and systems like Redis, Kafka, and NATS (software). Chrono's development and maintenance are influenced by organizations and projects like Servo, FreeBSD, OpenBSD, Debian, Ubuntu, Fedora Project, Arch Linux, and Gentoo.

Features

Chrono offers parsing and formatting compatible with RFC 3339, ISO 8601, and custom strftime-style patterns familiar from GNU and BSD toolchains. It supports timezone handling through integrations with databases and standards such as IANA time zone database, tzdata, and interoperability with Windows Time Zone definitions used by Microsoft Windows. Chrono exposes arithmetic operations for durations and intervals used in applications by organizations like Netflix, Spotify, Dropbox, and Airbnb. It also integrates with logging and tracing ecosystems such as Log4rs, env_logger, tracing (software), and observability platforms like Prometheus, Grafana, and Datadog.

Usage and Examples

Chrono's API is commonly demonstrated in tutorials and examples alongside frameworks and tools including Rustlings, The Rust Programming Language, Playground (Rust), and educational projects from Coursera, edX, and Udemy. Example usage often shows conversion between naive and timezone-aware types for interoperability with databases like MongoDB, Cassandra, and InfluxDB and cloud services including AWS Lambda, Google Cloud Functions, and Azure Functions. Chrono examples include formatting for internationalization contexts referencing organizations like Unicode Consortium, ICU (software), W3C, and IETF specifications.

Design and Architecture

Chrono's internal design emphasizes safety and correctness, leveraging Rust features and components such as Ownership (computer science), Borrow checker, and integrations with compilation targets supported by LLVM and rustc. It aligns with serialization and conversion traits from Serde (framework) and pattern matching idioms used in projects like Tokio, Async-std, and Mio (software). Chrono's handling of leap seconds, offsets, and calendar calculations reflects interoperability concerns raised by standards bodies including IANA, ISO, and IETF and implementations found in libraries for languages such as Python (programming language), Go (programming language), Java (programming language), C++, and JavaScript.

Compatibility and Performance

Chrono is designed to compile and run across targets supported by Rustup, cargo, and toolchains maintained by Mozilla and the Rust Foundation. Benchmarks and performance tuning are demonstrated in ecosystems such as Criterion.rs, bench (Rust), and CI services like GitHub Actions, Travis CI, CircleCI, GitLab CI/CD, and Azure Pipelines. Chrono's performance characteristics are relevant for high-throughput services operated by Twitter, Reddit, LinkedIn, Pinterest, Stripe, and Square (company), and for embedded contexts supported by ARM, x86, and RISC-V architectures used by vendors including Intel, AMD, NVIDIA, and Qualcomm.

Development and Community

Chrono's development community collaborates on platforms like GitHub, crates.io, Rust Forum, Users (Stack Overflow), and communication channels such as Discord, Matrix (protocol), and Zulip. Contributors include individuals and organizations associated with Mozilla, the Rust Foundation, Google, Microsoft, and open source distributions like Debian and Fedora Project. The project coordinates with standards and infrastructure from IETF, IANA, ISO, and Unicode Consortium and participates in events and conferences such as RustConf, FOSDEM, CppCon, PyCon, GopherCon, and KubeCon. Community resources include tutorials from YouTube, Medium (website), DEV Community, and documentation hosted alongside The Rust Programming Language materials.

Category:Rust libraries