The aeson package

[Tags: bsd3, library]

A JSON parsing and encoding library optimized for ease of use and high performance.

To get started, see the documentation for the Data.Aeson module below.

For release notes, see

Parsing performance on a late 2010 MacBook Pro (2.66GHz Core i7), for mostly-English tweets from Twitter's JSON search API:

Handling heavily-escaped text is a little more work. Here is parsing performance with Japanese tweets, where much of the text is entirely Unicode-escaped.

Encoding performance on the same machine and data:

(A note on naming: in Greek mythology, Aeson was the father of Jason.)


Dependenciesattoparsec (>=, base (==4.*), blaze-builder (>=, bytestring, containers, deepseq, hashable (>=, mtl, old-locale, syb, template-haskell (>=2.4), text (>=, time, unordered-containers (>=, vector (>=0.7.1)
Copyright(c) 2011, 2012, 2013 Bryan O'Sullivan (c) 2011 MailRank, Inc.
AuthorBryan O'Sullivan <>
MaintainerBryan O'Sullivan <>
CategoryText, Web, JSON
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Source repositoryhead: git clone git://
head: hg clone
Upload dateWed Sep 4 19:25:23 UTC 2013
Uploaded byBryanOSullivan
DistributionsDebian:, Fedora:, FreeBSD:, NixOS:
Downloads75364 total (17692 in last 30 days)



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