git-fast-export(1) Git Manual git-fast-export(1)
NAME
git-fast-export - Git data exporter
SYNOPSIS
git fast-export [<options>] [<revision-range>] [[--] <path>...]
DESCRIPTION
This program dumps the given revisions in a form suitable to be piped
into git fast-import.
You can use it as a human-readable bundle replacement (see git-
bundle(1)), or as a format that can be edited before being fed to git
fast-import in order to do history rewrites (an ability relied on by
tools like git filter-repo).
OPTIONS
--progress=<n>
Insert progress statements every <n> objects, to be shown by git
fast-import during import.
--signed-tags=(verbatim|warn-verbatim|warn-strip|strip|abort)
Specify how to handle signed tags. Since any transformation after the
export (or during the export, such as excluding revisions) can change
the hashes being signed, the signatures may become invalid.
When asking to abort (which is the default), this program will die
when encountering a signed tag. With strip, the tags will silently be
made unsigned, with warn-strip they will be made unsigned but a
warning will be displayed, with verbatim, they will be silently
exported and with warn-verbatim (or warn, a deprecated synonym), they
will be exported, but you will see a warning. verbatim and
warn-verbatim should only be used if you know that no transformation
affecting tags or any commit in their history will be performed by
you or by fast-export or fast-import, or if you do not care that the
resulting tag will have an invalid signature.
--signed-commits=(verbatim|warn-verbatim|warn-strip|strip|abort)
Specify how to handle signed commits. Behaves exactly as
--signed-tags, but for commits. Default is strip, which is the same
as how earlier versions of this command without this option behaved.
When exported, a signature starts with:
gpgsig <git-hash-algo> <signature-format>
where <git-hash-algo> is the Git object hash so either "sha1" or
"sha256", and <signature-format> is the signature type, so "openpgp",
"x509", "ssh" or "unknown".
For example, an OpenPGP signature on a SHA-1 commit starts with
gpgsig sha1 openpgp, while an SSH signature on a SHA-256 commit
starts with gpgsig sha256 ssh.
While all the signatures of a commit are exported, an importer may
choose to accept only some of them. For example git-fast-import(1)
currently stores at most one signature per Git hash algorithm in each
commit.
Note
This is highly experimental and the format of the data stream may
change in the future without compatibility guarantees.
--tag-of-filtered-object=(abort|drop|rewrite)
Specify how to handle tags whose tagged object is filtered out. Since
revisions and files to export can be limited by path, tagged objects
may be filtered completely.
When asking to abort (which is the default), this program will die
when encountering such a tag. With drop it will omit such tags from
the output. With rewrite, if the tagged object is a commit, it will
rewrite the tag to tag an ancestor commit (via parent rewriting; see
git-rev-list(1)).
-M, -C
Perform move and/or copy detection, as described in the git-diff(1)
manual page, and use it to generate rename and copy commands in the
output dump.
Note that earlier versions of this command did not complain and
produced incorrect results if you gave these options.
--export-marks=<file>
Dumps the internal marks table to <file> when complete. Marks are
written one per line as :markid SHA-1. Only marks for revisions are
dumped; marks for blobs are ignored. Backends can use this file to
validate imports after they have been completed, or to save the marks
table across incremental runs. As <file> is only opened and truncated
at completion, the same path can also be safely given to
--import-marks. The file will not be written if no new object has
been marked/exported.
--import-marks=<file>
Before processing any input, load the marks specified in <file>. The
input file must exist, must be readable, and must use the same format
as produced by --export-marks.
--mark-tags
In addition to labelling blobs and commits with mark ids, also label
tags. This is useful in conjunction with --export-marks and
--import-marks, and is also useful (and necessary) for exporting of
nested tags. It does not hurt other cases and would be the default,
but many fast-import frontends are not prepared to accept tags with
mark identifiers.
Any commits (or tags) that have already been marked will not be
exported again. If the backend uses a similar --import-marks file,
this allows for incremental bidirectional exporting of the repository
by keeping the marks the same across runs.
--fake-missing-tagger
Some old repositories have tags without a tagger. The fast-import
protocol was pretty strict about that, and did not allow that. So
fake a tagger to be able to fast-import the output.
--use-done-feature
Start the stream with a feature done stanza, and terminate it with a
done command.
--no-data
Skip output of blob objects and instead refer to blobs via their
original SHA-1 hash. This is useful when rewriting the directory
structure or history of a repository without touching the contents of
individual files. Note that the resulting stream can only be used by
a repository which already contains the necessary objects.
--full-tree
This option will cause fast-export to issue a "deleteall" directive
for each commit followed by a full list of all files in the commit
(as opposed to just listing the files which are different from the
commit's first parent).
--anonymize
Anonymize the contents of the repository while still retaining the
shape of the history and stored tree. See the section on ANONYMIZING
below.
--anonymize-map=<from>[:<to>]
Convert token <from> to <to> in the anonymized output. If <to> is
omitted, map <from> to itself (i.e., do not anonymize it). See the
section on ANONYMIZING below.
--reference-excluded-parents
By default, running a command such as git fast-export
master~5..master will not include the commit master~5 and will make
master~4 no longer have master~5 as a parent (though both the old
master~4 and new master~4 will have all the same files). Use
--reference-excluded-parents to instead have the stream refer to
commits in the excluded range of history by their sha1sum. Note that
the resulting stream can only be used by a repository which already
contains the necessary parent commits.
--show-original-ids
Add an extra directive to the output for commits and blobs,
original-oid <SHA1SUM>. While such directives will likely be ignored
by importers such as git-fast-import, it may be useful for
intermediary filters (e.g. for rewriting commit messages which refer
to older commits, or for stripping blobs by id).
--reencode=(yes|no|abort)
Specify how to handle encoding header in commit objects. When asking
to abort (which is the default), this program will die when
encountering such a commit object. With yes, the commit message will
be re-encoded into UTF-8. With no, the original encoding will be
preserved.
--refspec
Apply the specified refspec to each ref exported. Multiple of them
can be specified.
[<git-rev-list-args>...]
A list of arguments, acceptable to git rev-parse and git rev-list,
that specifies the specific objects and references to export. For
example, master~10..master causes the current master reference to be
exported along with all objects added since its 10th ancestor commit
and (unless the --reference-excluded-parents option is specified) all
files common to master~9 and master~10.
EXAMPLES
$ git fast-export --all | (cd /empty/repository && git fast-import)
This will export the whole repository and import it into the existing
empty repository. Except for reencoding commits that are not in UTF-8, it
would be a one-to-one mirror.
$ git fast-export master~5..master |
sed "s|refs/heads/master|refs/heads/other|" |
git fast-import
This makes a new branch called other from master~5..master (i.e. if
master has linear history, it will take the last 5 commits).
Note that this assumes that none of the blobs and commit messages
referenced by that revision range contains the string refs/heads/master.
ANONYMIZING
If the --anonymize option is given, git will attempt to remove all
identifying information from the repository while still retaining enough
of the original tree and history patterns to reproduce some bugs. The
goal is that a git bug which is found on a private repository will
persist in the anonymized repository, and the latter can be shared with
git developers to help solve the bug.
With this option, git will replace all refnames, paths, blob contents,
commit and tag messages, names, and email addresses in the output with
anonymized data. Two instances of the same string will be replaced
equivalently (e.g., two commits with the same author will have the same
anonymized author in the output, but bear no resemblance to the original
author string). The relationship between commits, branches, and tags is
retained, as well as the commit timestamps (but the commit messages and
refnames bear no resemblance to the originals). The relative makeup of
the tree is retained (e.g., if you have a root tree with 10 files and 3
trees, so will the output), but their names and the contents of the files
will be replaced.
If you think you have found a git bug, you can start by exporting an
anonymized stream of the whole repository:
$ git fast-export --anonymize --all >anon-stream
Then confirm that the bug persists in a repository created from that
stream (many bugs will not, as they really do depend on the exact
repository contents):
$ git init anon-repo
$ cd anon-repo
$ git fast-import <../anon-stream
$ ... test your bug ...
If the anonymized repository shows the bug, it may be worth sharing
anon-stream along with a regular bug report. Note that the anonymized
stream compresses very well, so gzipping it is encouraged. If you want to
examine the stream to see that it does not contain any private data, you
can peruse it directly before sending. You may also want to try:
$ perl -pe 's/\d+/X/g' <anon-stream | sort -u | less
which shows all of the unique lines (with numbers converted to "X", to
collapse "User 0", "User 1", etc into "User X"). This produces a much
smaller output, and it is usually easy to quickly confirm that there is
no private data in the stream.
Reproducing some bugs may require referencing particular commits or
paths, which becomes challenging after refnames and paths have been
anonymized. You can ask for a particular token to be left as-is or mapped
to a new value. For example, if you have a bug which reproduces with git
rev-list sensitive -- secret.c, you can run:
$ git fast-export --anonymize --all \
--anonymize-map=sensitive:foo \
--anonymize-map=secret.c:bar.c \
>stream
After importing the stream, you can then run git rev-list foo -- bar.c in
the anonymized repository.
Note that paths and refnames are split into tokens at slash boundaries.
The command above would anonymize subdir/secret.c as something like
path123/bar.c; you could then search for bar.c in the anonymized
repository to determine the final pathname.
To make referencing the final pathname simpler, you can map each path
component; so if you also anonymize subdir to publicdir, then the final
pathname would be publicdir/bar.c.
LIMITATIONS
Since git fast-import cannot tag trees, you will not be able to export
the linux.git repository completely, as it contains a tag referencing a
tree instead of a commit.
SEE ALSO
git-fast-import(1)
GIT
Part of the git(1) suite
Git 2.56.0 2026-09-27 git-fast-export(1)
git 2.56.0 - Generated Thu Oct 1 15:52:59 CDT 2026