.\" -*- mode: troff; coding: utf-8 -*-
.TH "nix3-flake-lock" "1" ""
.RS
.PP
\fBWarning\fR 
.br
This program is
\fB\fBexperimental\fR\fR
and its interface is subject to change.
.RE
.SH
Name
.LP
\fCnix flake lock\fR - create missing lock file entries
.SH
Synopsis
.LP
\fCnix flake lock\fR [\fIoption\fR\[u2026]] \fIflake-url\fR
.SH
Examples
.IP "\(bu" 3
Create the lock file for the flake in the current directory:
.LP
.EX
# 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)
.EE
.IP "\(bu" 3
Add missing inputs to the lock file for a flake in a different directory:
.LP
.EX
# nix flake lock \(ti/repos/another
warning: updating lock file '/home/myself/repos/another/flake.lock':
• Added input 'nixpkgs':
  'github:NixOS/nixpkgs/3d2d8f281a27d466fa54b469b5993f7dde198375' (2023-06-30)
.EE
.RS
.IP
\fBNote\fR
.IP
When trying to refer to a flake in a subdirectory, write \fC./another\fR
instead of \fCanother\fR.
Otherwise Nix will try to look up the flake in the registry.
.RE
.SH
Description
.LP
This command adds inputs to the lock file of a flake (\fCflake.lock\fR)
so that it contains a lock for every flake input specified in
\fCflake.nix\fR. Existing lock file entries are not updated.
.PP
If you want to update existing lock entries, use
\fB\fCnix flake update\fR\fR
.SH
Options
.SS
Common evaluation options
.IP "\(bu" 3
\fB\fC--arg\fR\fR \fIname\fR \fIexpr\fR
.IP
Pass the value \fIexpr\fR as the argument \fIname\fR to Nix functions.
.IP "\(bu" 3
\fB\fC--arg-from-file\fR\fR \fIname\fR \fIpath\fR
.IP
Pass the contents of file \fIpath\fR as the argument \fIname\fR to Nix functions.
.IP "\(bu" 3
\fB\fC--arg-from-stdin\fR\fR \fIname\fR
.IP
Pass the contents of stdin as the argument \fIname\fR to Nix functions.
.IP "\(bu" 3
\fB\fC--argstr\fR\fR \fIname\fR \fIstring\fR
.IP
Pass the string \fIstring\fR as the argument \fIname\fR to Nix functions.
.IP "\(bu" 3
\fB\fC--debugger\fR\fR
.IP
Start an interactive environment if evaluation fails.
.IP "\(bu" 3
\fB\fC--eval-store\fR\fR \fIstore-url\fR
.IP
The \fBURL of the Nix store\fR
to use for evaluation, i.e. to store derivations (\fC.drv\fR files) and inputs referenced by them.
.IP "\(bu" 3
\fB\fC--impure\fR\fR
.IP
Allow access to mutable paths and repositories.
.IP "\(bu" 3
\fB\fC--include\fR\fR / \fC-I\fR \fIpath\fR
.IP
Add \fIpath\fR to the Nix search path. The Nix search path is
initialized from the colon-separated \fB\fCNIX_PATH\fR\fR environment
variable, and is used to look up the location of Nix expressions using \fBpaths\fR enclosed in angle
brackets (i.e., \fC<nixpkgs>\fR).
.IP
For instance, passing
.LP
.EX
-I /home/eelco/Dev
-I /etc/nixos
.EE
.IP
will cause Nix to look for paths relative to \fC/home/eelco/Dev\fR and
\fC/etc/nixos\fR, in that order. This is equivalent to setting the
\fCNIX_PATH\fR environment variable to
.LP
.EX
/home/eelco/Dev:/etc/nixos
.EE
.IP
It is also possible to match paths against a prefix. For example,
passing
.LP
.EX
-I nixpkgs=/home/eelco/Dev/nixpkgs-branch
-I /etc/nixos
.EE
.IP
will cause Nix to search for \fC<nixpkgs/path>\fR in
\fC/home/eelco/Dev/nixpkgs-branch/path\fR and \fC/etc/nixos/nixpkgs/path\fR.
.IP
If a path in the Nix search path starts with \fChttp://\fR or \fChttps://\fR,
it is interpreted as the URL of a tarball that will be downloaded and
unpacked to a temporary location. The tarball must consist of a single
top-level directory. For example, passing
.LP
.EX
-I nixpkgs=https://github.com/NixOS/nixpkgs/archive/master.tar.gz
.EE
.IP
tells Nix to download and use the current contents of the \fCmaster\fR
branch in the \fCnixpkgs\fR repository.
.IP
The URLs of the tarballs from the official \fCnixos.org\fR channels
(see \fBthe manual page for \fCnix-channel\fR\fR) can be
abbreviated as \fCchannel:<channel-name>\fR. For instance, the
following two flags are equivalent:
.LP
.EX
-I nixpkgs=channel:nixos-21.05
-I nixpkgs=https://nixos.org/channels/nixos-21.05/nixexprs.tar.xz
.EE
.IP
You can also fetch source trees using \fBflake URLs\fR and add them to the
search path. For instance,
.LP
.EX
-I nixpkgs=flake:nixpkgs
.EE
.IP
specifies that the prefix \fCnixpkgs\fR shall refer to the source tree
downloaded from the \fCnixpkgs\fR entry in the flake registry. Similarly,
.LP
.EX
-I nixpkgs=flake:github:NixOS/nixpkgs/nixos-22.05
.EE
.IP
makes \fC<nixpkgs>\fR refer to a particular branch of the
\fCNixOS/nixpkgs\fR repository on GitHub.
.IP "\(bu" 3
\fB\fC--override-flake\fR\fR \fIoriginal-ref\fR \fIresolved-ref\fR
.IP
Override the flake registries, redirecting \fIoriginal-ref\fR to \fIresolved-ref\fR.
.SS
Common flake-related options
.IP "\(bu" 3
\fB\fC--commit-lock-file\fR\fR
.IP
Commit changes to the flake\(cqs lock file.
.IP "\(bu" 3
\fB\fC--inputs-from\fR\fR \fIflake-url\fR
.IP
Use the inputs of the specified flake as registry entries.
.IP "\(bu" 3
\fB\fC--no-registries\fR\fR
.IP
Don\(cqt allow lookups in the flake registries.
.RS
.IP
\fBDEPRECATED\fR
.IP
Use \fB\fC--no-use-registries\fR\fR instead.
.RE
.IP "\(bu" 3
\fB\fC--no-update-lock-file\fR\fR
.IP
Do not allow any updates to the flake\(cqs lock file.
.IP "\(bu" 3
\fB\fC--output-lock-file\fR\fR \fIflake-lock-path\fR
.IP
Write the given lock file instead of \fCflake.lock\fR within the top-level flake.
.IP "\(bu" 3
\fB\fC--override-input\fR\fR \fIinput-path\fR \fIflake-url\fR
.IP
Override a specific flake input (e.g. \fCdwarffs/nixpkgs\fR). This implies \fC--no-write-lock-file\fR.
.IP "\(bu" 3
\fB\fC--recreate-lock-file\fR\fR
.IP
Recreate the flake\(cqs lock file from scratch.
.RS
.IP
\fBDEPRECATED\fR
.IP
Use \fB\fCnix flake update\fR\fR instead.
.RE
.IP "\(bu" 3
\fB\fC--reference-lock-file\fR\fR \fIflake-lock-path\fR
.IP
Read the given lock file instead of \fCflake.lock\fR within the top-level flake.
.IP "\(bu" 3
\fB\fC--update-input\fR\fR \fIinput-path\fR
.IP
Update a specific flake input (ignoring its previous entry in the lock file).
.RS
.IP
\fBDEPRECATED\fR
.IP
Use \fB\fCnix flake update\fR\fR instead.
.RE
.SS
Logging-related options
.IP "\(bu" 3
\fB\fC--debug\fR\fR
.IP
Set the logging verbosity level to \(oqdebug\(cq.
.IP "\(bu" 3
\fB\fC--log-format\fR\fR \fIformat\fR
.IP
Set the format of log output; one of \fCraw\fR, \fCinternal-json\fR, \fCbar\fR or \fCbar-with-logs\fR.
.IP "\(bu" 3
\fB\fC--print-build-logs\fR\fR / \fC-L\fR
.IP
Print full build logs on standard error.
.IP "\(bu" 3
\fB\fC--quiet\fR\fR
.IP
Decrease the logging verbosity level.
.IP "\(bu" 3
\fB\fC--verbose\fR\fR / \fC-v\fR
.IP
Increase the logging verbosity level.
.SS
Miscellaneous global options
.IP "\(bu" 3
\fB\fC--help\fR\fR
.IP
Show usage information.
.IP "\(bu" 3
\fB\fC--offline\fR\fR
.IP
Disable substituters and consider all previously downloaded files up-to-date.
.IP "\(bu" 3
\fB\fC--option\fR\fR \fIname\fR \fIvalue\fR
.IP
Set the Nix configuration setting \fIname\fR to \fIvalue\fR (overriding \fCnix.conf\fR).
.IP "\(bu" 3
\fB\fC--refresh\fR\fR
.IP
Consider all previously downloaded files out-of-date.
.IP "\(bu" 3
\fB\fC--repair\fR\fR
.IP
During evaluation, rewrite missing or corrupted files in the Nix store. During building, rebuild missing or corrupted store paths.
.IP "\(bu" 3
\fB\fC--version\fR\fR
.IP
Show version information.
.RS
.LP
\fBNote\fR
.PP
See \fB\fCman nix.conf\fR\fR for overriding configuration settings with command line flags.
.RE