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

Note: if you use GHCi or Template Haskell, please see the README file for important details about building this package, and other packages that depend on it:

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.)


Versions0.1.0.0,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, (info)
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 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 Apr 4 04:58:17 UTC 2012
Uploaded byBryanOSullivan
DistributionsDebian:, Fedora:, FreeBSD:, NixOS:
Downloads146660 total (19826 in last 30 days)




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