Continuous Integration

Cuirass is a continuous integration tool for Guix. It can be used both for development and for providing substitutes to others.


GNU Cuirass is a Continuous Integration system provided for PantherX and GNU Guix.

Cuirass may be run manually or as service. In this document we will provide instructions about using Cuirass to build a custom package list and how to setup a Substitute Server.

Cuirass Spec Definition

In order to define build jobs for Cuirass, we need to define Specification List, a sample definition is as follows:

   '((#:name . "pantherx-packages")
     (#:load-path-inputs . ("guix"))
     (#:package-path-inputs . ("custom-packages"))
     (#:proc-input . "guix")
     (#:proc-file . "build-aux/cuirass/gnu-system.scm")
     (#:proc . cuirass-jobs)
     (#:proc-args . ((subset . "manifests")
                     (manifests . (("config" . "manifest.scm")))
                     (systems . ("x86_64-linux"))))
     (#:inputs . (((#:name . "guix")
                   (#:url . "git://")
                   (#:load-path . ".")
                   (#:branch . "master")
                   (#:no-compile? . #t))
                  ((#:name . "config")
                   (#:url . "git://")
                   (#:load-path . ".")
                   (#:branch . "ci")
                   (#:no-compile? . #t))
      		      ((#:name . "custom-packages")
      		       (#:url . "git://")
      		       (#:load-path . ".")
      		       (#:branch . "master")
      		       (#:no-compile? . #t))))))

Each Cuirass job consist of a list of inputs that needs to load in order to prepare for starting the job and a proc which runs by Cuirass.

  • name: a title for each job that used for identification of Cuirass jobs
  • load-path-inputs: list of inputs that are needed to run current job successfully
  • package-path-inputs: Cuirass uses this list to search for package definitions to build
  • proc-input: the input which job execution process should load from, by default we use guix (referring to official guix repository) input for build
  • proc-file: location of file which job execution procedure should load from. for Package build procedure, we use build-aux/cuirass/gnu-system.scm as default value
  • proc: name of Job procedure inside proc-file. default value is cuirass-jobs
  • proc-args: arguments we want to pass to job execution procedure
    • subset: defines how should cuirass load packages for build. this could be "manifests" string, or a list of package names we want to build
    • systems: list of system architectures to build, (default x86_64-linux)
    • manifests: pointing to a relative location to based on input and file of manifest which contains package list
  • inputs: list of input definitions for job, each containing following parameters:
    • name: name of input
    • url: input repository url
    • branch: repository branch which input should load from
    • load-path: relative path in repository that input should load
    • no-compile?: —

Running Cuirass manually

In order to run cuirass manually, you need to install cuirass package. later you can run it using following command:

cuirass --specifications=/path/to/spec.scm --database=/path/to/database.db

you could also add following command-line arguments:

  • --one-shot: Evaluate and build jobs only once
  • --cache-directory=DIR: Use DIR for storing repository data
  • --fallback: Fall back to building when the substituter fails.
  • --specifications=SPECFILE: Add specifications from SPECFILE to database.
  • --database=DB: Use DB to store build results.
  • --ttl=DURATION: Keep build results live for at least DURATION.
  • --port=NUM: Port of the HTTP server.
  • --listen=HOST: Listen on the network interface for HOST
  • --interval=N: Wait N seconds between each poll
  • --use-substitutes: Allow usage of pre-built substitutes
  • --threads=N: Use up to N kernel threads

Run Cuirass as a Service

In order to run Cuirass as a service, first you need to define job specification, then you need to add it to list of services inside System Configuration File:

(define %cuirass-specs
   #~(list ... ))

   (services (cons*
		(service cuirass-service-type
            (host "")
            (port 8080)
            (specifications %cuirass-spec)
            (use-substitutes? #t)
            (fallback? #t)))

to find a detailed description about Cuirass Service Details, you can see official document

Provide web access for built packages

in order to serve built packages for clients, first you need to generate authorization keys on server:

guix archive --generate-key

your generated key is located in /etc/guix/.

now you need to add guix-publish service as follows:

(services (cons*
		   (service guix-publish-service-type
			      (host "")
			      (port 3000)
			      (compression '(("gzip" 9) ("lzip" 9)))))

Client Configuration

In order to allow clients to access build server, we need to register server’s public key on clients using guix archive command:

guix archive --authorize < /path/to/

now we need to modify guix-daemon service and add build server’s url to that:

(append (modify-services %base-services
      config => (guix-configuration
         (substitute-urls '("http://server_url:3000"

Known Issues

Input Name Issue

There is a weird issue in cuirass, that when we start some input name with p letter, cuirass execution will fail:

2019-06-25T19:17:35 evaluating spec 'hello-spec'
          17 (apply-smob/1 #<catch-closure 128b780>)
In ice-9/boot-9.scm:
    705:2 16 (call-with-prompt _ _ #<procedure default-prompt-handle…>)
In ice-9/eval.scm:
    619:8 15 (_ #(#(#<directory (guile-user) 1316140>)))
   293:34 14 (_ #(#(#(#(#(#(#(#(#(#(#(…) …) …) …) …) …) …) …) …) …) …))
    159:9 13 (_ _)
    619:8 12 (_ #(#(#(#<module (#{ g18}#) 1339640>) #<store-co…> …) …))
   626:19 11 (_ #(#(#(#<module (#{ g18}#) 1339640>) #<store-co…> …) …))
In guix/store.scm:
  1794:24 10 (run-with-store _ _ #:guile-for-build _ #:system _ # _)
In guix/channels.scm:
    498:2  9 (_ _)
    455:2  8 (_ _)
In guix/monads.scm:
    482:9  7 (_ _)
In guix/store.scm:
   1667:8  6 (_ _)
In guix/gexp.scm:
    708:2  5 (_ _)
In guix/monads.scm:
    482:9  4 (_ _)
In guix/gexp.scm:
   573:13  3 (_ _)
In guix/store.scm:
  1667:13  2 (_ _)
In guix/gexp.scm:
    210:2  1 (lower-object #f _ #:target _)
   189:36  0 (lookup-compiler #f)

guix/gexp.scm:189:36: In procedure lookup-compiler:
In procedure struct_vtable: Wrong type argument in position 1 (expecting struct): #f

Some deprecated features have been used.  Set the environment
variable GUILE_WARN_DEPRECATED to "detailed" and rerun the
program to get more information.  Set it to "no" to suppress
this message.
2019-06-25T19:17:36 failed to evaluate spec 'hello-spec'

for now we don’t have any fix for this, and as a workaround, you need to aware about your input names that not to start with p letter.

Reference: Guix-Devel mailing list

Same Repository URL for inputs

using same URL for multiple inputs (for example inputs for different branches of a git repository) could cause issues during build. since Cuirass creates just one cache folder for each repository, switching between these branches during build, could cause the build process to be failed.

PantherX & (unofficial) GNU Guix Wiki.

Last update: 2023-11-11 21:56:46 +0000 | Apache-2.0

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