Definitions of terms and acronyms used in the Zstandard plugin and CLI documentation.
API — Application Programming Interface. The public methods and types exposed by the plugin (e.g. Zstandard().compress(), decompress()).
ARM64 — 64-bit ARM architecture. Used by Apple Silicon (M1/M2/M3), many Android devices, and some Windows/Linux machines.
CLI — Command-Line Interface. The zstandard_cli package provides both an in-code API and command-line tools (dart run zstandard_cli:compress, decompress).
Compression level — Integer from 1 to 22 controlling the trade-off between speed and compression ratio. Level 1 is fastest; level 22 gives the smallest output.
Dart — The programming language used for the plugin and CLI. See dart.dev.
Decompress — Convert Zstandard-compressed bytes back to the original uncompressed data.
FFI — Foreign Function Interface. The mechanism in Dart that allows calling native (C/C++) code. The plugin uses FFI to call the zstd C library on Android, iOS, macOS, Windows, and Linux.
Flutter — The UI toolkit and framework. The main zstandard package is a Flutter plugin; zstandard_cli is pure Dart (no Flutter).
Federated plugin — A Flutter plugin that delegates to platform-specific implementations (e.g. zstandard_android, zstandard_ios) rather than implementing everything in one package. The zstandard_native package holds the shared C source (facebook/zstd) used by all native implementations and the CLI; it is published to pub.dev as part of the release set.
Frame — A Zstandard-compressed unit of data with a header and optional checksum. The API compresses and decompresses one frame at a time (or a single buffer that may contain a frame).
Isolate — A Dart concurrency unit. The native implementations may run compression/decompression in a separate isolate so the UI thread is not blocked.
LCOV — A format for code coverage data. flutter test --coverage and the coverage package produce LCOV (e.g. lcov.info) for tools like Codecov.
Native — Code that runs on the host OS (C/C++, Kotlin, Swift, etc.) as opposed to Dart or JavaScript. The zstd library is native; the plugin wraps it via FFI.
Precompiled — Built in advance (e.g. the CLI’s native libraries for macOS, Windows, Linux are precompiled and shipped with the package).
pub.dev — The default package repository for Dart and Flutter. Packages are published there with dart pub publish.
Uint8List — A Dart type for a list of unsigned 8-bit bytes. The plugin’s compress and decompress APIs use Uint8List for input and output.
WASM / WebAssembly — A binary format for running code in browsers. The zstandard_web implementation compiles zstd to WASM and loads it via JavaScript.
x64 / x86_64 — 64-bit Intel/AMD architecture. Supported on macOS, Windows, Linux, and Android emulators.
zstd — Zstandard. The compression algorithm and library developed by Meta (Facebook). The plugin and CLI wrap the official facebook/zstd C library.
Zstandard — Same as zstd; the full name of the algorithm and format.