The hydra-print package

[ Tags: bsd3, concurrency, library, program ] [ Propose Tags ]

Output from parallel subprocesses is an ugly, many-headed beast. Piping though hydra-print provides an NCurses interface to a dynamic set output streams, displayed without interleaving. This is a common problem, for example, with parallel compiles, or data-processing scripts.

Specifically, this small library will split the screen when parallelism occurs, and unsplit it when the parallelism is finished (i.e. dynamically growing and losing "heads"). The io-streams library is used for all stream inputs.


Dependencies async, base (<=4.7), bytestring, containers, directory, filepath, io-streams, mtl, ncurses, process, random, semigroups, text, time, transformers, unix [details]
License BSD3
Copyright 2013, Ryan Newton
Author Ryan Newton
Maintainer Ryan Newton <>
Category Concurrency
Home page
Source repo head: git clone git://
Uploaded Mon Apr 15 20:00:28 UTC 2013 by RyanNewton
Distributions NixOS:
Executables hydra-head, hydra-view
Downloads 1160 total (21 in the last 30 days)
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Status Docs not available [build log]
All reported builds failed as of 2016-12-21 [all 7 reports]
Hackage Matrix CI


  • Scripting
    • Parallel
      • Scripting.Parallel.ThreadPool
  • UI
    • UI.HydraPrint


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