THthayne·Aug 20, 2026
But google already built a tool to do exactly that: https://github.com/google/copybara
In Google has stopped pushing Git tags for some Android source codegoogle
copybara
Java2017–2026
google / copybara
copybara
Copybara: A tool for transforming and moving code between repositories.
20Distinct people
21Mentions
0Explicit recommenders
3.9KGitHub stars
What to know before exploring
What it is
Copybara: A tool for transforming and moving code between repositories.
GitHub
Where it is used
No documented product use was verified in the last source check.
What people are saying
No recommendation phrase was found in the indexed comments.
No classified warning is attached to this page. Read the discussions before treating silence as approval.
Also in these discussions
No other repository is repeatedly linked in the same discussions.
This week on Hacker News
Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 9:28:18 AM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by year21 dated mentions
Observed mentions: 2017-03-15 22:55:50 UTC to 2026-08-20 04:16:12 UTC.
* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2017 | 2017-01-01 00:00:00 UTC | 2018-01-01 00:00:00 UTC | 2 | 1 | 1 |
| 2018 | 2018-01-01 00:00:00 UTC | 2019-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2019 | 2019-01-01 00:00:00 UTC | 2020-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2020 | 2020-01-01 00:00:00 UTC | 2021-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2021 | 2021-01-01 00:00:00 UTC | 2022-01-01 00:00:00 UTC | 4 | 1 | 3 |
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 4 | 0 | 4 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 2 | 1 | 1 |
| 2026 (partial) | 2026-01-01 00:00:00 UTC | 2027-01-01 00:00:00 UTC | 4 | 1 | 3 |
What Hacker News says
4 sourcesI already shared git-fetch-file in another comment here, but the .git-remote-files manifests seem a lot nicer than whatever this thing does:
[file "lib/util.py" from "https://github.com/example/tools.git"]
commit = a1b2c3d4e5f6789abcdef0123456789abcdef01
branch = master
comment = Common utility function
[file "config.json" from "https://github.com/example/tools.git"]
commit = b2c3d4e5f6789abcdef0123456789abcdef012
branch = master
target = vendor
comment = Configuration from tools repo
[file "helper.js" from "https://github.com/another/project.git"]
commit = c3d4e5f6789abcdef0123456789abcdef0123
branch = main
comment = Helper from another project
vs
core.workflow(
name = "default",
origin = git.github_origin(
url = "https://github.com/google/copybara.git",
Read the rest
ref = "master",
),
destination = git.destination(
url = "file:///tmp/foo",
),
# Copy everything but don't remove a README_INTERNAL.txt file if it exists.
destination_files = glob(["third_party/copybara/**"], exclude = ["README_INTERNAL.txt"]),
authoring = authoring.pass_thru("Default email <default@default.com>"),
transformations = [
core.replace(
before = "//third_party/bazel/bashunit",
after = "//another/path:bashunit",
paths = glob(["**/BUILD"])),
core.move("", "third_party/copybara")
],
)
There seems to be an absolute ton of reference at https://github.com/google/copybara/blob/master/docs/referenc..., whereas I feel like all the people using git-fetch-file just want files from other repos, and sometimes to make some changes on those.
Ha! This post comes right at the time where I finally got around to open sourcing the patches I made to provide Perforce support which I use at my gamedev studio[0].
I find it kind of funny that perforce support was not included, only git support seems to exist in any meaningful way: despite the primary use of copybara being for releasing internal google code (which lives in Piper, a fork of Perforce).
I actually got a bit worried when looking at the git history before making the PR, because there's a lot of Gerrit Change-ID markers (meaning there's some gerrit code review system somewhere which I'm not privvy too) and I might have submitted a PR which never gets upstreamed..
I feel the same pang of pain from the lack of a perforce version of Gerrit/Rietveld.. but, you can't ask for everything!
[0]: https://github.com/google/copybara/pull
Read the rest
Google copybara: moving code between repositories
300 points · Open discussion