Configuration and Administration¶
The nixbuild.net Shell¶
nixbuild.net does not have a web frontend for administrating your account. Instead all administration and configuration is done through a terminal-based shell accessible over SSH like this:
ssh eu.nixbuild.net shell
By default, the SSH key you used when registering is used both for performing Nix builds and for accessing the administration shell. You can, however, add more SSH keys to your account and give the keys different permissions within your account. It doesn't matter what user name you connect with, only your SSH key will be checked. This also means that the same SSH keys can't be added to multiple nixbuild.net accounts.
The nixbuild.net shell doesn't yet have support for command history or many other features that you could expect from a proper shell. However, you can use the rlwrap program to mitigate this:
rlwrap ssh eu.nixbuild.net shell
This will make things like Up/Down arrow keys and CTRL-R work as you would expect.
The greeting screen showed each time you log in to the shell also includes a list of all top-level commands, and instructions on how the help system works:
•••••••••••••••••••••••••••• ••••••• nixbuild.net ••••••• •••••••••••••••••••••••••••• Welcome to nixbuild.net! This shell allows you to administer your account and retrieve information about your nix builds. Account id: IIERI7 Unbilled CPU hours: 0 Free build time left: 49:59:59 Available shell commands: help Show help settings Configure account or SSH key settings usage Show resource usage ssh-keys Manage your public SSH keys billing Billing activation and info signing-keys Manage Nix signing keys tokens Manage auth tokens builds Manage builds Run 'help COMMAND' for help on individual shell commands. For help on subcommands run 'COMMAND SUBCOMMAND --help'. For more documentation, see: https://docs.nixbuild.net/configuration
To see how much you've been using nixbuild.net, run the
nixbuild.net> usage Resources used since 2021-03-01 -------------------- Build count : 51 Successful builds : 51 Wall time : 5.79 s CPU time : 6.26 s The usage metrics only includes non-discarded builds and includes any free build time consumed. To find out your currently accumulated cost, or see past invoices, use the 'billing info' command.
By default, the
usage command will show your usage during the current month.
You can also show the previous month's usage with the
-l option and the total
usage with the
nixbuild.net> usage -h usage - Show resource usage Usage: usage [(-t|--total) | (-l|--last-month) | (-m|--this-month)] Available options: -t,--total Show total usage -l,--last-month Show last month's usage -m,--this-month Show this month's usage (default) -h,--help Show this help text
To get information on how much money you've spent on builds, use the billing commands.
You can manage your nixbuild.net settings with the
Show all settings by running
nixbuild.net> settings --show Account settings ---------------- access-tokens <no entries> allow-build true allow-shell true always-substitute true caches <no entries> inject-fs-randomness false + keep-builds-running true max-cpu-hours-per-month 2000 reuse-build-failures true reuse-build-timeouts false substituters https://cache.nixos.org trusted-public-keys cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= settings-from-drv-env false settings-from-ssh-env true Settings with a '+' sign have been assigned a value, others are using system defaults.
Set, get and reset individual settings with
nixbuild.net> settings keep-builds-running --set true nixbuild.net> settings keep-builds-running --show keep-builds-running true nixbuild.net> settings keep-builds-running --reset nixbuild.net> settings keep-builds-running --show keep-builds-running false
Complex settings like lists have the options
--remove instead of
You can revert all account settings by running
settings --reset. Note that this
doesn't revert any of the settings you might have configured for individual SSH
You can list, add and remove ssh keys associated with your account using the
ssh-keys - Manage your public SSH keys Usage: ssh-keys SUBCOMMAND Available options: -h,--help Show this help text Available subcommands: list List SSH keys add Add a key remove Remove a key get Get settings overrides for an SSH key set Set settings overrides for an SSH key unset Unset settings overrides for an SSH key
nixbuild.net supports fetching build dependencies from binary caches. This can make builds a lot faster, especially if your network upload speed is poor.
By default nixbuild.net uses cache.nixos.org to
perform substitution, just like an ordinary Nix installation does. You can
disable substitution by setting substituters to an
empty list. You can also add other substituters that you want nixbuild.net to
use when it runs your builds. Remember that when adding new substituters you
also need to add their public keys using the
trusted-public-keys setting. The
trusted-public-keys settings work the same in nixbuild.net
as they do for a local Nix installation.
nixbuild.net only supports substituting from publicly available HTTP caches. If you need support for using private substituters, contact [email protected].
You can use public Cachix caches for substitution. Simply
add a substituter with an URL on the form
You see the public key of a cache if you visit
in your browser.
Uploading to external caches¶
nixbuild.net also supports uploading store paths to external caches. Any cache added to the caches setting will be populated with the transitive closure of the build's inputs and outputs. Uploading of a build's inputs happens in parallel to running the build, and the outputs are uploaded as soon as the build finishes.
Utilizing nixbuild.net for performing cache uploads means that you don't have to do that yourself as an extra step after the build is done. If also combined with remote store building, you can cut down network traffic to a minimum which can really improve performance in some cases.
Currently, nixbuild.net only supports uploading to Cachix caches. See the documentation of the caches setting for instruction on how to configure Cachix caches. If you would like to see support for additional cache types in nixbuild.net, please contact [email protected].
Using nixbuild.net as a substituter¶
You can set up Nix to use nixbuild.net as a substituter on your local machine or CI builder. This can improve performance in some situtations, and it is very useful in custom CI setups where you want to integrate nixbuild.net. Note that even if you set up nixbuild.net as a substituter, you still need to use an SSH key to access it.
To set up nixbuild.net as a substituter, first fetch your public signing key through the shell:
nixbuild.net> signing-keys account-keys nixbuild.net/bob-1:8tJU22/XxyINhP+wM65gwSIlg0rrQrmWhFf5+8u8F/s=
Then add the substituter and signing key to your existing configuration in
substituters = ... ssh://eu.nixbuild.net trusted-public-keys = ... nixbuild.net/bob-1:8tJU22/XxyINhP+wM65gwSIlg0rrQrmWhFf5+8u8F/s=
You can use trusted-substituters instead of substituters to not use nixbuild.net as a substituter by default, but make it available for selection on the command line.
billing commands let you manage billing for your account:
nixbuild.net> billing --help billing - Billing activation and info Usage: billing SUBCOMMAND Available options: -h,--help Show this help text Available subcommands: activate Enable non-free usage edit Edit your credit card details info Display billing details
To be able to use nixbuild.net beyond the initial free build hours you need
to enable billing by running
billing activate. You can do this at any time,
and as soon as you've done it your account will be able to run non-free builds.
If you run out of free build hours before you have activated billing, you will
not be able to run any more builds. As soon as you activate billing, you will
be able to run builds again.
When activating billing, you will be directed to a
Stripe-hosted web page where you can enter your billing
address and credit card details. When running
billing activate you need to
provide your company name or full name (for personal accounts) like this:
nixbuild.net> billing activate Acme LLC Billing has been activated for your account. You will now be able to use nixbuild.net beyond your free CPU hours. If you still have free CPU hours left, you will not be charged until they have been used up. IMPORTANT: Visit the time-limited url below to enter your credit card details and billing address. https://billing.stripe.com/session/_J7U1XtINfG0dMoQayAJegz3kcfSsryu If you want to change your payment method after the above url has expired, use the command 'billing edit'. If you need to make any other billing changes, please contact [email protected]. If you fail to provide valid billing details your account may be locked.
If you need to change your credit card details at any time, you can use the
billing edit command. If you need to change any other billing details, you
must contact [email protected].
billing info command lets you see the amount of the upcoming invoice, as
well as past invoices.
Use the command
list builds -r to list your currently running builds:
nixbuild.net> list builds -r 70196 2020-08-23 21:05:10Z 3.21 s 1 CPU [In queue] /nix/store/ky3fzyaw0hibjpkpyx8s89fhaprxhrba-zlib-1.2.11.drv 70195 2020-08-23 21:05:10Z 3.66 s 1 CPU [In queue] /nix/store/k8ir9nqbqhlriqs6r97vi19im5rn9nkd-xz-5.2.5.drv 70194 2020-08-23 21:05:09Z 3.40 s 4 CPUs [Running] /nix/store/5k1i3j15dzqkf8rcga0ap7fjk1q7xj9a-perl-5.30.3.drv 70193 2020-08-23 21:05:08Z 4.18 s 2 CPUs [Running] /nix/store/7cgb9m0dm9facpzqbyfkz1i0snd2n1y7-gnum4-1.4.18.drv
-r option to also show historic builds. By default, at most 500
builds are listed, but that can be adjusted with the