154 stable releases

new 3.19.0 May 18, 2024
3.16.11 Apr 29, 2024
3.15.7 Mar 27, 2024
3.9.13 Dec 31, 2023
3.6.2 Nov 30, 2023

#61 in Unix APIs

Download history 13190/week @ 2024-02-03 12703/week @ 2024-02-10 12954/week @ 2024-02-17 10961/week @ 2024-02-24 13618/week @ 2024-03-02 15105/week @ 2024-03-09 14862/week @ 2024-03-16 14595/week @ 2024-03-23 14393/week @ 2024-03-30 6766/week @ 2024-04-06 6715/week @ 2024-04-13 6312/week @ 2024-04-20 7571/week @ 2024-04-27 5190/week @ 2024-05-04 2926/week @ 2024-05-11 2999/week @ 2024-05-18

19,610 downloads per month


63K SLoC

msrv repology build status pipeline status

license maintenance-status dependency status OpenSSF best practices

Shine On You Crazy Diamond! Try to Avoid Chance!


Syd is a rock-solid user-space kernel to sandbox applications on Linux>=5.19. Syd is similar to Bubblewrap, Firejail, GVisor, and minijail. Syd is secure by default, and intends to provide a simple interface over various intricate Linux sandboxing mechanisms such as LandLock, Namespaces, ptrace, and seccomp-{bpf,notify}. You may run Syd as a regular user, with no extra privileges, and you can even set Syd as your login shell. A brief overview of Syd's capabilities are as follows:

Read the fine manuals of syd, libsyd, gosyd, plsyd, pysyd, rbsyd, syd.el and watch the asciicasts Memory Sandboxing, PID Sandboxing, Network Sandboxing, and Sandboxing Emacs with syd. Join the CTF event at https://ctftime.org/event/2178 and try to read the file /etc/CTF¹ on syd.chesswob.org with ssh user/pass: syd.

Maintained by Ali Polatel. Up-to-date sources can be found at https://gitlab.exherbo.org/sydbox/sydbox.git and bugs/patches can be submitted to https://gitlab.exherbo.org/groups/sydbox/-/issues. Follow toots with the #sydbox hashtag and discuss in #sydbox on Libera Chat.

¹: The SHA256 checksum is f1af8d3946546f9d3b1af4fe15f0209b2298166208d51a481cf51ac8c5f4b294.

²: That cat's something I can't explain!


~512K SLoC