nix3-flake-lock(1) General Commands Manual nix3-flake-lock(1)

Warning
This program is experimental and its interface is subject to change.

nix flake lock - create missing lock file entries

nix flake lock [option…] flake-url

•
Create the lock file for the flake in the current directory:
# nix flake lock
warning: creating lock file '/home/myself/repos/testflake/flake.lock':
• Added input 'nix':
  'github:NixOS/nix/9fab14adbc3810d5cc1f88672fde1eee4358405c' (2023-06-28)
• Added input 'nixpkgs':
  'github:NixOS/nixpkgs/3d2d8f281a27d466fa54b469b5993f7dde198375' (2023-06-30)
•
Add missing inputs to the lock file for a flake in a different directory:
# nix flake lock ~/repos/another
warning: updating lock file '/home/myself/repos/another/flake.lock':
• Added input 'nixpkgs':
  'github:NixOS/nixpkgs/3d2d8f281a27d466fa54b469b5993f7dde198375' (2023-06-30)
Note
When trying to refer to a flake in a subdirectory, write ./another instead of another. Otherwise Nix will try to look up the flake in the registry.

This command adds inputs to the lock file of a flake (flake.lock) so that it contains a lock for every flake input specified in flake.nix. Existing lock file entries are not updated.

If you want to update existing lock entries, use nix flake update

•
--arg name expr
Pass the value expr as the argument name to Nix functions.
•
--arg-from-file name path
Pass the contents of file path as the argument name to Nix functions.
•
--arg-from-stdin name
Pass the contents of stdin as the argument name to Nix functions.
•
--argstr name string
Pass the string string as the argument name to Nix functions.
•
--debugger
Start an interactive environment if evaluation fails.
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--eval-store store-url
The URL of the Nix store to use for evaluation, i.e. to store derivations (.drv files) and inputs referenced by them.
•
--impure
Allow access to mutable paths and repositories.
•
--include / -I path
Add path to search path entries used to resolve lookup paths
This option may be given multiple times.
Paths added through -I take precedence over the nix-path configuration setting and the NIX_PATH environment variable.
•
--override-flake original-ref resolved-ref
Override the flake registries, redirecting original-ref to resolved-ref.
•
--commit-lock-file
Commit changes to the flake’s lock file.
•
--inputs-from flake-url
Use the inputs of the specified flake as registry entries.
•
--no-registries
Don’t allow lookups in the flake registries.
DEPRECATED
Use --no-use-registries instead.
•
--no-update-lock-file
Do not allow any updates to the flake’s lock file.
•
--output-lock-file flake-lock-path
Write the given lock file instead of flake.lock within the top-level flake.
•
--override-input input-path flake-url
Override a specific flake input (e.g. dwarffs/nixpkgs). This implies --no-write-lock-file.
•
--recreate-lock-file
Recreate the flake’s lock file from scratch.
DEPRECATED
Use nix flake update instead.
•
--reference-lock-file flake-lock-path
Read the given lock file instead of flake.lock within the top-level flake.
•
--update-input input-path
Update a specific flake input (ignoring its previous entry in the lock file).
DEPRECATED
Use nix flake update instead.
•
--debug
Set the logging verbosity level to ‘debug’.
•
--log-format format
Set the format of log output; one of raw, internal-json, bar or bar-with-logs.
•
--print-build-logs / -L
Print full build logs on standard error.
•
--quiet
Decrease the logging verbosity level.
•
--verbose / -v
Increase the logging verbosity level.

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--help
Show usage information.
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--offline
Disable substituters and consider all previously downloaded files up-to-date.
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--option name value
Set the Nix configuration setting name to value (overriding nix.conf).
•
--refresh
Consider all previously downloaded files out-of-date.
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--repair
During evaluation, rewrite missing or corrupted files in the Nix store. During building, rebuild missing or corrupted store paths.
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--version
Show version information.

Note

See man nix.conf for overriding configuration settings with command line flags.