fastgron: A JSON to GRON Converter That's 40 Times Faster Than Gron
Hello HN! I want to introduce fastgron, my new project. fastgron is a JSON to GRON converter, built to be incredibly fast – it's 40 times faster than Gron. GRON is a tool for making JSON greppable, but it can slow down with larger files. With fastgron, even a 200MB JSON file can be converted in just 1 second. Key features include streaming conversion for memory efficiency and an optimized path reconstruction for faster operations. It leverages C++ and the simdjson and fast_io libraries for speed. I welcome all feedback, suggestions, or questions. Thank you!
fastgron: A JSON to GRON Converter That's 40 Times Faster Than Gron launched on May 28, 2023 with 23 votes, #1,545 of 4,910 launches that month and more than 75% of that year's launches. The site was still online in September 2026, 3 years on.
In plain words
fastgron converts JSON files into GRON format, which makes JSON data greppable for easier searching and filtering. Built in C++ using optimized libraries, it handles large files efficiently through streaming conversion and fast path reconstruction. The tool is designed for developers and data analysts who need to query or analyze JSON data quickly, particularly with large files that would slow down traditional GRON tools.
written from the facts on this page · September 2026
From the sources
High-performance JSON to GRON (greppable, flattened JSON) converter - adamritter/fastgron
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