Launch a web app in the default browser.

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LTS Haskell 11.0:
Stackage Nightly 2018-03-12:
Latest on Hackage:

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MIT licensed by Michael Snoyman
Maintained by michael@snoyman.com

Module documentation for


This handles cross-platform launching and inserts Javascript code to ping the server. When the server no longer receives pings, it shuts down.


  • process package bump

  • Improvements to ping's javascript script. #494

  • Relax upper bound on process


  • Don't launch if server fails; kill server on exit #537 #541


  • make host configurable too (fixes #538) #539

  • Support wai/warp 3.2

Allow blaze-builder 0.4

  • Support for Win64
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