Article · Wikipedia archive · Last revised May 27, 2026

Snap (web framework)

Snap is a web framework for developing web applications written in the functional programming language Haskell.

Last revised
May 27, 2026
Read time
≈ 2 min
Length
447 w
Citations
22
Source
Wikipedia ↗
Snap
Original authorsGregory Collins, Doug Beardsley1
DeveloperSnap Team
Initial releaseMay 2010 (2010-05)
Stable release
1.1.3.22 / July 19, 2023 (2023-07-19)
Written inHaskell
Operating systemCross-platform: Unix, Unix-like, macOS; Windows NT
PlatformIA-32, x86-64
Available inEnglish
TypeWeb framework
LicenseBSD
Websitesnapframework.com
Repositorygithub.com/snapframework

Snap is a web framework for developing web applications written in the functional programming language Haskell.34

Overview

The Snap framework consists of the following:

  • snap-core,5 a generic Haskell web server API.
  • snap-server,6 a fast7 HTTP server that implements the snap-core interface.
  • Heist,8 an HTML-based templating system for generating pages that allows you to bind Haskell functionality to HTML tags for a clean separation of view and backend code, much like Lift's snippets. Heist is self-contained and can be used independently.
  • Snaplets,9 a high-level system for building modular web applications.
  • Built-in snaplets for templating, session management, and authentication.
  • Third party snaplets for features including file uploads, database connectivity (PostgreSQL, MongoDB, etc.), generation of JavaScript from Haskell code, and more.
  • The Snap monad for stateful access to HTTP requests and responses.10

Snap runs on both Windows NT and Unix-like platforms. Snap uses the Iteratee input/output (I/O) model,11 As of version 1.0, its I/O is implemented with io-streams.

Usage

Snap is used by Silk,12 JanRain,1314 Racemetric,15 Lee Paste's Financial Blog,1617 SooStone Inc, and Group Commerce. Snap is also used as a lightweight, standalone Haskell server. The static site generator Hakyll uses Snap for its preview mode.18

Other Haskell web frameworks

References

References

  1. Snap Framework Team. "Snap: A Haskell Web Framework: About". Snap Framework.com.
  2. "snapframework/snap". GitHub.com.
  3. Collins, Gregory; Beardsley, Doug (January–February 2011). "The Snap Framework: A Web Toolkit for Haskell" (PDF). IEEE Internet Computing. 15 (1): 84–87. Bibcode:2011IIC....15a..84C. doi:10.1109/mic.2011.21.
  4. Biscardi, Chris (2014). Snap for Beginners. Gumroad.
  5. "snap-core". Hackage.org.
  6. "snap-server". Hackage.org.
  7. "Snap 0.3 benchmarks with GHC 7.0.1". Snap Framework.com. Retrieved 2014-03-02.
  8. Snap Framework Team. "Snap: A Haskell Web Framework: Heist Tutorial". Snap Framework.com.
  9. Snap Framework Team. "Snap: A Haskell Web Framework: Snaplet Directory". Snap Framework.com.
  10. "Snap.Core". Hackage.org.
  11. "InfoQ Interview: Gregory Collins on High Performance Web Apps with Snap and Haskell". Sep 12, 2011.
  12. "FP Complete Case Study – Silk – Structured Content Management" (PDF). FP Complete. Retrieved 2014-03-02.
  13. "FP Complete Case Study – JanRain – User Management System" (PDF). FP Complete. Retrieved 2014-03-02.
  14. "Blog tutorial on Snap and PostgreSQL". JanRain. Retrieved 2014-03-02.
  15. Hoersten, Luke. "Haskell Snap App in Production". Retrieved 2014-03-02.
  16. "Lee Paste". Lee Paste's Financial Blog.
  17. Done, Chris. "lpaste source code". GitHub. Retrieved 2014-03-02.
  18. Van der Jeugt, Jasper. "Hakyll". JasperVdJ.be. Retrieved 2024-11-09.
  19. "scotty: Haskell web framework inspired by Ruby's Sinatra, using WAI and Warp". Hackage.org.
  20. "Spock: Another Haskell web framework for rapid development". Hackage.org.
  21. "MFlow: stateful, RESTful web framework". Hackage.org.
  22. "miso: A tasty Haskell front-end framework". Hackage.org.
External links