Hi all,

The Snap team is pleased to announce the release of Snap 0.2.7. This release contains critical fixes for correctness bugs and all Snap users should upgrade to the latest version (including snap-server, a point fix for an embarrassing release issue) at their earliest convenience.

Changes since 0.2.6

New features:

  • the “snap” project starter was reorganized by new Snap contributor Shane O’Brien (duairc).

  • The HTTP parser in snap-server has a couple of new criterion benchmarks courtesy of Aycan Irican.

  • the default/simple Snap backend should now have properly functioning timeout support.


  • fixed a serious HTTP spec bug; the HTTP spec says that 304 responses are never to contain message bodies, but we were sending ours with “Transfer-encoding: chunked”, causing a spurious “0\r\n\r\n” sequence to cause pipelined HTTP sessions to go out of sync.

  • fixed a bug in the route function related to variable capture.

  • fixed a couple of minor bugs related to iteratee buffering.

  • squashed a space leak.

  • some fixes related to sendfile() support, especially relating to timeouts. On a temporary basis this has required us to pull in quite a bit of internal code from the sendfile library, because that library uses GHC’s IO manager for event handling. (Not so good for us on libev!)

Upcoming in 0.3

Carl and Shane have been working very hard on the upcoming 0.3 branch release. The snap project starter executable has been spawned out of the snap-core repository and completely rewritten; the new version features a “development mode” which runs your web handlers using hint. This will allow changes in your Haskell code to be reflected instantly in the server output, without the overhead of a shutdown/startup cycle on the server. We’re really excited about this feature, it gets us a lot closer to having the best of both worlds: rapid development to rival PHP or Python, as well as high performance in “production” mode.