ajson

Read JSON from a file and execute a specified JSONPath expression

$ ajson '[$..json[?(@.path)]]' [path/to/file.json]

$ cat [path/to/file.json] | ajson '[$..json[?(@.path)]]'

$ ajson '[avg($..price)]' '[https://example.com/api/]'

$ echo '[3]' | ajson '[2 * pi * $]'

ajson [OPTION]... <filter> [file...]
ajson [OPTION]... --arg name value [name value...] <filter> [file...]

-h, --help
    Display help and exit

-V, --version
    Output version information

-n, --null-input
    Use null input instead of reading file

-s, --slurp
    Read entire input into single array

-r, --raw-output
    Output strings without quotes

-c, --color-output
    Colorize output

--unbuffered
    Flush output after each record

--arg
    Define variable from command-line

--argjson
    Define JSON variable from string

--slurpfile
    Slurp file contents into variable

--stream
    Parse in streaming fashion

--seq
    Wrap filtered output in array

ajson is a high-performance command-line tool for parsing, filtering, and transforming JSON data.

Written in Zig, it offers jq-like syntax and semantics while achieving significantly higher speeds—up to 10x faster than jq on large datasets.

It supports common operations like selecting fields (.field), array slicing, object merging, and complex pipes. Ideal for log processing, API data manipulation, and DevOps scripts.

Key strengths include low memory usage, streaming support for huge files, and native binary distribution. Unlike jq, it compiles filters at runtime for efficiency.

ajson reads JSON from files or stdin, applies user-defined filters, and outputs formatted or raw results. It's cross-platform (Linux, macOS, Windows) and lightweight (~1MB binary).

While highly compatible with jq, some advanced modules may lack support. Perfect for users needing jq power without performance overhead.

Not 100% jq compatible; some esoteric features/modules unsupported. Best on Linux x86_64. Streaming mode may alter output order.

Via prebuilt binaries from GitHub releases or build from source: zig build -Drelease-safe.

ajson '.users[].name' data.json
Extract names from users array.

Developed by Vladimir Vivkin in 2023 using Zig. Inspired by jq limitations on speed. v0.1.0 released Oct 2023; active development with benchmarks vs jq.

jq(1), jless(1), gron(1), json_pp(1)