1. We can mark packages as install or reject
2. We can order actions/clauses. When backtracking the action that came later will be the first we try to backtrack on
3. We can order the choices of a dependency - we try them left to right.

apt upgrade is hard The apt upgrade commands implements a safe version of dist-upgrade that essentially calculates the dist-upgrade, and then undoes anything that would cause a package to be removed, but it (unlike its apt-get counterpart) allows the solver to install new packages. Now, consider the following package is installed:

X Depends: A (= 1)   B

An upgrade from A=1 to A=2 is available. What should happen? The classic solver would choose to remove X in a dist-upgrade, and then upgrade A, so it s answer is quite clear: Keep back the upgrade of A. The new solver however sees two possible solutions:

1. Install B to satisfy X Depends A (= 1) B.
2. Keep back the upgrade of A

Which one does it pick? This depends on the order in which it sees the upgrade action for A and the dependency, as it will backjump chronologically. So

1. If it gets to the dependency first, it marks A=1 for install to satisfy A (= 1). Then it gets to the upgrade request, which is just A Depends A (= 2) A (= 1) and sees it is satisfied already and is content.
2. If it gets to the upgrade request first, it marks A=2 for install to satisfy A (= 2). Then later it gets to X Depends: A (= 1) B, sees that A (= 1) is not satisfiable, and picks B.

We have two ways to approach this issue:

1. We always order upgrade requests last, so they will be kept back in case of conflicting dependencies
2. We require that, for apt upgrade a currently satisfied dependency must be satisfied by currently installed packages, hence eliminating B as a choice.

Recommends are hard too See if you have a X Recommends: A (= 1) and a new version of A, A (= 2), the solver currently will silently break the Recommends in some cases. But let s explore what the behavior of a X Recommends: A (= 1) in combination with an available upgrade of A (= 2) should be. We could say the rule should be:

• An upgrade should keep back A instead of breaking the Recommends
• A dist-upgrade should either keep back A or remove X (if it is obsolete)

This essentially leaves us the same choices as for the previous problem, but with an interesting twist. We can change the ordering (and we already did), but we could also introduce a new rule, promotions :

A Recommends in an installed package, or an upgrade to that installed package, where the Recommends existed in the installed version, that is currently satisfied, must continue to be satisfied, that is, it effectively is promoted to a Depends.

This neatly solves the problem for us. We will never break Recommends that are satisfied. Likewise, we already have a Recommends demotion rule:

A Recommends in an installed package, or an upgrade to that installed package, where the Recommends existed in the installed version, that is currently unsatisfied, will not be further evaluated (it is treated like a Suggests is in the default configuration).

Whether we should be allowed to break Suggests with our decisions or not (the old autoremover did not, for instance) is a different decision. Should we promote currently satisified Suggests to Depends as well? Should we follow currently satisified Suggests so the solver sees them and doesn t autoremove them, but treat them as optional?

tightening of versioned dependencies Another case of versioned dependencies with alternatives that has complex behavior is something like

X Depends: A (>= 2)   B
X Recommends: A (>= 2)   B

In both cases, installing X should upgrade an A < 2 in favour of installing B. But a naive SAT solver might not. If your request to keep A installed is encoded as A (= 1) A (= 2), then it first picks A (= 1). When it sees the Depends/Recommends it will switch to B. We can solve this again as in the previous example by ordering the keep A installed requests after any dependencies. Notably, we will enqueue the common dependencies of all A versions first before selecting a version of A, so something may select a version for us.

version narrowing instead of version choosing A different approach to dealing with the issue of version selection is to not select a version until the very last moment. So instead of selecting a version to satisfy A (>= 2) we instead translate

Depends: A (>= 2)

into two rules:

1. The package selection rule:

    Depends: A
   

   This ensures that any version of A is installed (i.e. it adds a version choice clause, A (= 1) A (= 2) in an example with two versions for A.
2. The version narrowing rule:

    Conflicts: A (<< 2)
   

   This outright would reject a choice of A (= 1).

So now we have 3 kinds of clauses:

1. package selection
2. version narrowing
3. version selection

If we process them in that order, we should surely be able to find the solution that best matches the semantics of our Debian dependency model, i.e. selecting earlier choices in a dependency before later choices in the face of version restrictions. This still leaves one issue: What if our maintainer did not use Depends: A (>= 2) B but e.g. Depends: A (= 3) B A (= 2). He d expect us to fall back to B if A (= 3) is not installable, and not to B. But we d like to enqueue A and reject all choices other than 3 and 2. I think it s fair to say: Don t do that, then here.

Implementing strict pinning correctly APT knows a single candidate version per package, this makes the solver relatively deterministic: It will only ever pick the candidate, or an installed version. This also happens to significantly reduce the search space which is good - less backtracking. An uptodate system will only ever have one version per package that can be installed, so we never actually have to choose versions. But of course, APT allows you to specify a non-candidate version of a package to install, for example:

apt install foo/oracular-proposed

The way this works is that the core component of the previous solver, which is the pkgDepCache maintains what essentially amounts to an overlay of the policy that you could see with apt-cache policy. The solver currently however validates allowed version choices against the policy directly, and hence finds these versions are not allowed and craps out. This is an interesting problem because the solver should not be dependent on the pkgDepCache as the pkgDepCache initialization (Building dependency tree...) accounts for about half of the runtime of APT (until the Y/n prompt) and I d really like to get rid of it. But currently the frontend does go via the pkgDepCache. It marks the packages in there, building up what you could call a transaction, and then we translate it to the new solver, and once it is done, it translates the result back into the pkgDepCache. The current implementation of allowed version is implemented by reducing the search space, i.e. every dependency, we outright ignore any non-allowed versions. So if you have a version 3 of A that is ignored a Depends: A would be translated into A (= 2) A (= 1). However this has two disadvantages. (1) It means if we show you why A could not be installed, you don t even see A (= 3) in the list of choices and (2) you would need to keep the pkgDepCache around for the temporary overrides. So instead of actually enforcing the allowed version rule by filtering, a more reasonable model is that we apply the allowed version rule by just marking every other version as not allowed when discovering the package in the from depcache translation layer. This doesn t really increase the search space either but it solves both our problem of making overrides work and giving you a reasonable error message that lists all versions of A.

pulling up common dependencies to minimize backtracking cost One of the common issues we have is that when we have a dependency group

 A   B   C   D 

we try them in order, and if one fails, we undo everything it did, and move on to the next one. However, this isn t perhaps the best choice of operation. I explained before that one thing we do is queue the common dependencies of a package (i.e. dependencies shared in all versions) when marking a package for install, but we don t do this here: We have already lowered the representation of the dependency group into a list of versions, so we d need to extract the package back out of it. This can of course be done, but there may be a more interesting solution to the problem, in that we simply enqueue all the common dependencies. That is, we add n backtracking levels for n possible solutions:

1. We enqueue the common dependencies of all possible solutions deps(A)&deps(B)&deps(C)&deps(D)
2. We decide (adding a decision level) not to install D right now and enqueue deps(A)&deps(B)&deps(C)
3. We decide (adding a decision level) not to install C right now and enqueue deps(A)&deps(B)
4. We decide (adding a decision level) not to install B right now and enqueue A

Now if we need to backtrack from our choice of A we hopefully still have a lot of common dependencies queued that we do not need to redo. While we have more backtracking levels, each backtracking level would be significantly cheaper, especially if you have cheap backtracking (which admittedly we do not have, yet anyway). The caveat though is: It may be pretty expensive to find the common dependencies. We need to iterate over all dependency groups of A and see if they are in B, C, and D, so we have a complexity of roughly #A * (#B+#C+#D) Each dependency group we need to check i.e. is X Y in B meanwhile has linear cost: We need to compare the memory content of two pointer arrays containing the list of possible versions that solve the dependency group. This means that X Y and Y X are different dependencies of course, but that is to be expected they are. But any dependency of the same order will have the same memory layout. So really the cost is roughly N^4. This isn t nice. You can apply various heuristics here on how to improve that, or you can even apply binary logic:

1. Enqueue common dependencies of A B C D
2. Move into the left half, enqueue of A B
3. Again divide and conquer and select A.

This has a significant advantage in long lists of choices, and also in the common case, where the first solution should be the right one. Or again, if you enqueue the package and a version restriction instead, you already get the common dependencies enqueued for the chosen package at least.

1. Do you have a policy of not trying to silence past students who have been treated badly?
2. Do you take all sexual assaults seriously including wedgies and dakking?
3. Do you take all violence at school seriously? Even if there s no blood? Even if the victim says they don t want to make an issue of it?
4. What are your procedures to deal with misbehaviour from teachers? Do the students all know how to file complaints? Do they know that they can file a complaint if they aren t the victim?
5. Does the school have policies against homophobia and transphobia and are they enforced?
6. Does the school offer free psychological assistance to students and staff who need it? NB This only applies to private schools like YV that have huge amounts of money, public schools can t afford that.
7. Are serious incidents investigated by people who are independent of the school and who don t have a vested interest in keeping things quiet?
8. Do you encourage students to seek external help from organisations like the ones on the resources list of the Grace Tame Foundation [5]? Having your own list of recommended external organisations would be good too.

• Teachers are nice people how dare you criticise them. Teachers like any other large group of people includes good and bad people. The issue is how well the good people are supported in doing good things, how much effort is spent on tracking down and removing the bad people, and how much effort is spent training people to be the best version of themselves. Also my father worked as a teacher so I really don t think that all teachers are bad.
• Teachers are overworked and underpaid and you shouldn t criticise them. When a school has 25 students in a class whose parents each pay $30,000 per annum the school can afford to pay as much as is necessary. Arguments about teachers being overworked and underpaid are a criticism of the organisation of private school and of government priorities for public schools not a counter argument to criticisms of the way schools operate.
• When I went to school no bad things happened. Did you go to YV? If not then your experience isn t relevant to this post.
• I was a prefect at YV and didn t see any bad things, if you saw bad things you should have reported it to me. I was not aware of any prefect who had a history of opposing bullying in previous years, I can think of some who had a history of encouraging it. Prefects were selected on the basis of supporting the system so anyone who would be expected to try to change things would have been rejected.
• Children will make false and frivolous claims so we should ignore most of what they say, therefore complaints should only come from parents. Children have considerably less ability to lie than adults and the senior teachers are much better at detecting lies than most people. Sorting out accurate claims from false ones shouldn t be difficult but if you reject all criticism as false claims then you will definitely miss reports of bad things and allow problems to continue.
• I had a hard time at school and I turned out fine. If having bad things done to you doesn t make you want to protect others from the same things then you didn t turn out fine at all.
• Kids need to toughen up to survive the real world. The real world that I live in doesn t involve much violence at all, even having someone raise their voice at work is uncommon. Of the situations where being tough due to my experience at YV has been useful almost all of them involve me choosing to help someone I don t know in a dangerous situation while other men pretend that they didn t even notice it. The real solution is to create a world with less violence and a large part of that involves improving schools.

• [1] https://en.wikipedia.org/wiki/Streisand_effect
• [2] https://en.wikipedia.org/wiki/Pantsing
• [3] https://www.yvg.vic.edu.au/siteassets/Whistleblower-Policy-FINAL.pdf
• [4] https://tinyurl.com/254crjqr
• [5] https://www.thegracetamefoundation.org.au/resources

Changes in version 0.1.3 (2024-05-13)

• Add an xdr argument to disable XDR for an approx. threefold speed increase (Travers Ching and Dirk in #6)
• Use R_NO_REMAP and Rf_* prefix for API calls
• Minor continuous integration updates

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

How does it work? Solver3 is a fully backtracking dependency solving algorithm that defers choices to as late as possible. It starts with an empty set of packages, then adds the manually installed packages, and then installs packages automatically as necessary to satisfy the dependencies. Deferring the choices is implemented multiple ways: First, all install requests recursively mark dependencies with a single solution for install, and any packages that are being rejected due to conflicts or user requests will cause their reverse dependencies to be transitively marked as rejected, provided their or group cannot be solved by a different package. Second, any dependency with more than one choice is pushed to a priority queue that is ordered by the number of possible solutions, such that we resolve a b before a b c. Not just by the number of solutions, though. One important point to note is that optional dependencies, that is, Recommends, are always sorting after mandatory dependencies. Do note on that: Recommended packages do not nest in backtracking - dependencies of a Recommended package themselves are not optional, so they will have to be resolved before the next Recommended package is seen in the queue. Another important step in deferring choices is extracting the common dependencies of a package across its version and then installing them before we even decide which of its versions we want to install - one of the dependencies might cycle back to a specific version after all. Decisions about package levels are recorded at a certain decision level, if we reach a conflict we backtrack to the previous decision level, mark the decision we made (install X) in the inverse (DO NOT INSTALL X), reset all the state all decisions made at the higher level, and restore any dependencies that are no longer resolved to the work queue.

Comparison to SAT solver design. If you have studied SAT solver design, you ll find that essentially this is a DPLL solver without pure literal elimination. A pure literal eliminitation phase would not work for a package manager: First negative pure literals (packages that everything conflicts with) do not exist, and positive pure literals (packages nothing conflicts with) we do not want to mark for install - we want to install as little as possible (well subject, to policy). As part of the solving phase, we also construct an implication graph, albeit a partial one: The first package installing another package is marked as the reason (A -> B), the same thing for conflicts (not A -> not B). Once we have added the ability to have multiple parents in the implication graph, it stands to reason that we can also implement the much more advanced method of conflict-driven clause learning; where we do not jump back to the previous decision level but exactly to the decision level that caused the conflict. This would massively speed up backtracking.

What changes can you expect in behavior? The most striking difference to the classic APT solver is that solver3 always keeps manually installed packages around, it never offers to remove them. We will relax that in a future iteration so that it can replace packages with new ones, that is, if your package is no longer available in the repository (obsolete), but there is one that Conflicts+Replaces+Provides it, solver3 will be allowed to install that and remove the other. Implementing that policy is rather trivial: We just need to queue obsolete replacement as a dependency to solve, rather than mark the obsolete package for install. Another critical difference is the change in the autoremove behavior: The new solver currently only knows the strongest dependency chain to each package, and hence it will not keep around any packages that are only reachable via weaker chains. A common example is when gcc-<version> packages accumulate on your system over the years. They all have Provides: c-compiler and the libtool Depends: gcc c-compiler is enough to keep them around.

New features The new option --no-strict-pinning instructs the solver to consider all versions of a package and not just the candidate version. For example, you could use apt install foo=2.0 --no-strict-pinning to install version 2.0 of foo and upgrade - or downgrade - packages as needed to satisfy foo=2.0 dependencies. This mostly comes in handy in use cases involving Debian experimental or the Ubuntu proposed pockets, where you want to install a package from there, but try to satisfy from the normal release as much as possible. The implication graph building allows us to implement an apt why command, that while not as nicely detailed as aptitude, at least tells you the exact reason why a package is installed. It will only show the strongest dependency chain at first of course, since that is what we record.

What is left to do? At the moment, error information is not stored across backtracking in any way, but we generally will want to show you the first conflict we reach as it is the most natural one; or all conflicts. Currently you get the last conflict which may not be particularly useful. Likewise, errors currently are just rendered as implication graphs of the form [not] A -> [not] B -> ..., and we need to put in some work to present those nicely. The test suite is not passing yet, I haven t really started working on it. A challenge is that most packages in the test suite are manually installed as they are mocked, and the solver now doesn t remove those. We plan to implement the replacement logic such that foo can be replaced by foo2 Conflicts/Replaces/Provides foo without needing to be automatically installed. Improving the backtracking to be non-chronological conflict-driven clause learning would vastly enhance our backtracking performance. Not that it seems to be an issue right now in my limited testing (mostly noble 64-bit-time_t upgrades). A lot of that complexity you have normally is not there because the manually installed packages and resulting unit propagation (single-solution Depends/Reverse-Depends for Conflicts) already ground us fairly far in what changes we can actually make. Once all the stuff has landed, we need to start rolling it out and gather feedback. On Ubuntu I d like automated feedback on regressions (running solver3 in parallel, checking if result is worse and then submitting an error to the error tracker), on Debian this could just be a role email address to send solver dumps to. At the same time, we can also incrementally start rolling this out. Like phased updates in Ubuntu, we can also roll out the new solver as the default to 10%, 20%, 50% of users before going to the full 100%. This will allow us to capture regressions early and fix them.

• After a severe (non-COVID) infection, an ongoing interaction between my immune system and my metabolism have stopped my body from being able to do aerobic respiration.¹⁰
• I don't know why or how, but my mitochondria don't work properly anymore.¹¹
• This means that if I use too much energy, my body isn't able to make enough energy to catch up, and I have severe symptoms over the next few days as my body tries to manage the consequences.
• Those symptoms aren't limited to fatigue: I've developed flu-like symptoms and even fevers, limbs so heavy they felt paralyzed, tachycardia in response to even the slightest activity.

• [US] A Long COVID "moonshot" effort, drafted in April 2024 by Senator Sanders. Contact your representatives and encourage them to support it. Ask them to ensure the effort includes support for ME/CFS and other related conditions and PASCS.
• [Canada] National ME/FM Action recommended participation in public budget consultation processes and made a submission. Though the 2024 consultation is closed, you can still contact your MP to improve awareness and advocate for budgetary support. It may also be worth contacting your MLA to advocate for better PASC care in provincial clinics.
• [UK] Action for ME is advocating for a cross-Government Delivery Plan for ME/CFS care in England. Contact your MP and encourage them to support it.
• [Other] MEAction also regularly hosts government advocacy campaigns in the US, UK, and Scotland.

• Student: anuragxone

• Student: Nikolaos

• Student: Nathan D

• Student: Sreehari Prasad TM

• Student: hanbings

• Student: xuantengh

• Student: Krysztal Huang

Note: I've been awfully silent here for the past ... (checks notes) oh dear, 3 months! But that's not because I've been idle, quite the contrary, I've been very busy but just didn't have time to write about anything. So I've taken it upon myself to write something about my work this week, and published this post on the Tor blog which I copy here for a broader audience. Let me know if you like this or not.

https://git.torproject.org/

https://gitlab.torproject.org/

Where is the code? Normally, nothing should be lost. All repositories in gitolite have been either explicitly migrated by their owners, forcibly migrated by the sysadmin team (TPA), or explicitly destroyed at their owner's request. An exhaustive rewrite map translates gitolite projects to GitLab projects. Some of those projects actually redirect to their parent in cases of empty repositories that were obvious forks. Destroyed repositories redirect to the GitLab front page. Because the migration happened progressively, it's technically possible that commits pushed to gitolite were lost after the migration. We took great care to avoid that scenario. First, we adopted a proposal (TPA-RFC-36) in June 2023 to announce the transition. Then, in March 2024, we locked down all repositories from any further changes. Around that time, only a handful of repositories had changes made after the adoption date, and we examined each repository carefully to make sure nothing was lost. Still, we built a diff of all the changes in the git references that archivists can peruse to check for data loss. It's large (6MiB+) because a lot of repositories were migrated before the mass migration and then kept evolving in GitLab. Many other repositories were rebuilt in GitLab from parent to rebuild a fork relationship which added extra references to those clones. A note to amateur archivists out there, it's probably too late for one last crawl now. The Git repositories now all redirect to GitLab and are effectively unavailable in their original form. That said, the GitWeb site was crawled into the Internet Archive in February 2024, so at least some copy of it is available in the Wayback Machine. At that point, however, many developers had already migrated their projects to GitLab, so the copies there were already possibly out of date compared with the repositories in GitLab. Software Heritage also has a copy of all repositories hosted on Gitolite since June 2023 and have continuously kept mirroring the repositories, where they will be kept hopefully in eternity. There's an issue where the main website can't find the repositories when you search for gitweb.torproject.org, instead search for git.torproject.org. In any case, if you believe data is missing, please do let us know by opening an issue with TPA.

Why? This is an old project in the making. The first discussion about migrating from gitolite to GitLab started in 2020 (almost 4 years ago). But going further back, the first GitLab experiment was in 2016, almost a decade ago. The current GitLab server dates from 2019, replacing Trac for issue tracking in 2020. It was originally supposed to host only mirrors for merge requests and issue trackers but, naturally, one thing led to another and eventually, GitLab had grown a container registry, continuous integration (CI) runners, GitLab Pages, and, of course, hosted most Git repositories. There were hesitations at moving to GitLab for code hosting. We had discussions about the increased attack surface and ways to mitigate that, but, ultimately, it seems the issues were not that serious and the community embraced GitLab. TPA actually migrated its most critical repositories out of shared hosting entirely, into specific servers (e.g. the Puppet Git repository is just on the Puppet server now), leveraging Git's decentralized nature and removing an entire attack surface from our infrastructure. Some of those repositories are mirrored back into GitLab, but the authoritative copy is not on GitLab. In any case, the proposal to migrate from Gitolite to GitLab was effectively just formalizing a fait accompli.

How to migrate from Gitolite / cgit to GitLab The progressive migration was a challenge. If you intend to migrate between hosting platforms, we strongly recommend to make a "flag day" during which you migrate all repositories at once. This ensures a smoother transition and avoids elaborate rewrite rules. When Gitolite access was shutdown, we had repositories on both GitLab and Gitolite, without a clear relationship between the two. A priori, the plan then was to import all the remaining Gitolite repositories into the legacy/gitolite namespace, but that seemed wasteful, particularly for large repositories like Tor Browser which uses nearly a gigabyte of disk space. So we took special care to avoid duplicating repositories. When the mass migration started, only 71 of the 538 Gitolite repositories were Migrated to GitLab in the gitolite.conf file. So, given that we had hundreds of repositories to migrate:, we developed some automation to "save time". We already automate similar ad-hoc tasks with Fabric, so we used that framework here as well. (Our normal configuration management tool is Puppet, which is a poor fit here.) So a relatively large amount of Python code was produced to basically do the following:

1. check if all on-disk repositories are listed in gitolite.conf (and vice versa) and either add missing repositories or delete them from disk if garbage
2. for each repository in gitolite.conf, if its category is marked Migrated to GitLab, skip, otherwise;
3. find a matching GitLab project by name, prompt the user for multiple matches
4. if a match is found, redirect if the repository is non-empty
   • we have GitLab projects that look like the real thing, but are only present to host migrated Trac issues
   • in such cases we cloned the Gitolite project locally and pushed to the existing repository instead
5. otherwise, a new repository is created in the legacy/gitolite namespace, using the "import" mechanism in GitLab to automatically import the repository from Gitolite, creating redirections and updating gitolite.conf to document the change

User repositories (those under the user/ directory in Gitolite) were handled specially. First, the existing redirection map was checked to see if a similarly named project was migrated (so that, e.g. user/dgoulet/tor is properly treated as a fork of tpo/core/tor). Then the parent project was forked in GitLab and the Gitolite project force-pushed to the fork. This allows us to show the fork relationship in GitLab and, more importantly, benefit from the "pool" feature in GitLab which deduplicates disk usage between forks. Sometimes, we found no such relationships. Then we simply imported multiple repositories with similar names in the legacy/gitolite namespace, sometimes creating forks between user repositories, on a first-come-first-served basis from the gitolite.conf order. The code used in this migration is now available publicly. We encourage other groups planning to migrate from Gitolite/GitWeb to GitLab to use (and contribute to) our fabric-tasks repository, even though it does have its fair share of hard-coded assertions. The main entry point is the gitolite.mass-repos-migration task. A typical migration job looked like:

anarcat@angela:fabric-tasks$ fab -H cupani.torproject.org gitolite.mass-repos-migration 
[...]
INFO: skipping project project/help/infra in category Migrated to GitLab
INFO: skipping project project/help/wiki in category Migrated to GitLab
INFO: skipping project project/jenkins/jobs in category Migrated to GitLab
INFO: skipping project project/jenkins/tools in category Migrated to GitLab
INFO: searching for projects matching fastlane
INFO: Successfully connected to https://gitlab.torproject.org
import gitolite project project/tor-browser/fastlane into gitlab legacy/gitolite/project/tor-browser/fastlane with desc 'Tor Browser app store and deployment configuration for Fastlane'? [Y/n] 
INFO: importing gitolite project project/tor-browser/fastlane into gitlab legacy/gitolite/project/tor-browser/fastlane with desc 'Tor Browser app store and deployment configuration for Fastlane'
INFO: building a new connect to cupani
INFO: defaulting name to fastlane
INFO: importing project into GitLab
INFO: Successfully connected to https://gitlab.torproject.org
INFO: loading group legacy/gitolite/project/tor-browser
INFO: archiving project
INFO: creating repository fastlane (fastlane) in namespace legacy/gitolite/project/tor-browser from https://git.torproject.org/project/tor-browser/fastlane into https://gitlab.torproject.org/legacy/gitolite/project/tor-browser/fastlane
INFO: migrating Gitolite repository project/tor-browser/fastlane to GitLab project legacy/gitolite/project/tor-browser/fastlane
INFO: uploading 399 bytes to /srv/git.torproject.org/repositories/project/tor-browser/fastlane.git/hooks/pre-receive
INFO: making /srv/git.torproject.org/repositories/project/tor-browser/fastlane.git/hooks/pre-receive executable
INFO: adding entry to rewrite_map /home/anarcat/src/tor/tor-puppet/modules/profile/files/git/gitolite2gitlab.txt
INFO: modifying gitolite.conf to add: "config gitweb.category = Migrated to GitLab"
INFO: rewriting gitolite config /home/anarcat/src/tor/gitolite-admin/conf/gitolite.conf to change project project/tor-browser/fastlane to category Migrated to GitLab
INFO: skipping project project/bridges/bridgedb-admin in category Migrated to GitLab
[...]

In the above, you can see migrated repositories skipped then the fastlane project being archived into GitLab. Another example with a later version of the script, processing only user repositories and showing the interactive prompt and a force-push into a fork:

$ fab -H cupani.torproject.org  gitolite.mass-repos-migration --include 'user/.*' --exclude '.*tor-?browser.*'
INFO: skipping project user/aagbsn/bridgedb in category Migrated to GitLab
[...]
INFO: skipping project user/phw/atlas in category Migrated to GitLab
INFO: processing project user/phw/obfsproxy (Philipp's obfsproxy repository) in category Users' development repositories (Attic)
INFO: Successfully connected to https://gitlab.torproject.org
INFO: user repository detected, trying to find fork phw/obfsproxy
WARNING: no existing fork found, entering user fork subroutine
INFO: found 6 GitLab projects matching 'obfsproxy' (https://gitweb.torproject.org/user/phw/obfsproxy.git)
0 legacy/gitolite/debian/obfsproxy
1 legacy/gitolite/debian/obfsproxy-legacy
2 legacy/gitolite/user/asn/obfsproxy
3 legacy/gitolite/user/ioerror/obfsproxy
4 tpo/anti-censorship/pluggable-transports/obfsproxy
5 tpo/anti-censorship/pluggable-transports/obfsproxy-legacy
select parent to fork from, or enter to abort: ^G4
INFO: repository is not empty: in-pack: 2104, packs: 1, size-pack: 414
fork project tpo/anti-censorship/pluggable-transports/obfsproxy into legacy/gitolite/user/phw/obfsproxy^G [Y/n] 
INFO: loading project tpo/anti-censorship/pluggable-transports/obfsproxy
INFO: forking project user/phw/obfsproxy into namespace legacy/gitolite/user/phw
INFO: waiting for fork to complete...
INFO: fork status: started, sleeping...
INFO: fork finished
INFO: cloning and force pushing from user/phw/obfsproxy to legacy/gitolite/user/phw/obfsproxy
INFO: deleting branch protection: <class 'gitlab.v4.objects.branches.ProjectProtectedBranch'> =>  'id': 2723, 'name': 'master', 'push_access_levels': [ 'id': 2864, 'access_level': 40, 'access_level_description': 'Maintainers', 'deploy_key_id': None ], 'merge_access_levels': [ 'id': 2753, 'access_level': 40, 'access_level_description': 'Maintainers' ], 'allow_force_push': False 
INFO: cloning repository git-rw.torproject.org:/srv/git.torproject.org/repositories/user/phw/obfsproxy.git in /tmp/tmp6orvjggy/user/phw/obfsproxy
Cloning into bare repository '/tmp/tmp6orvjggy/user/phw/obfsproxy'...
INFO: pushing to GitLab: https://gitlab.torproject.org/legacy/gitolite/user/phw/obfsproxy
remote: 
remote: To create a merge request for bug_10887, visit:        
remote:   https://gitlab.torproject.org/legacy/gitolite/user/phw/obfsproxy/-/merge_requests/new?merge_request%5Bsource_branch%5D=bug_10887        
remote: 
[...]
To ssh://gitlab.torproject.org/legacy/gitolite/user/phw/obfsproxy
 + 2bf9d09...a8e54d5 master -> master (forced update)
 * [new branch]      bug_10887 -> bug_10887
[...]
INFO: migrating repo
INFO: migrating Gitolite repository https://gitweb.torproject.org/user/phw/obfsproxy.git to GitLab project https://gitlab.torproject.org/legacy/gitolite/user/phw/obfsproxy
INFO: adding entry to rewrite_map /home/anarcat/src/tor/tor-puppet/modules/profile/files/git/gitolite2gitlab.txt
INFO: modifying gitolite.conf to add: "config gitweb.category = Migrated to GitLab"
INFO: rewriting gitolite config /home/anarcat/src/tor/gitolite-admin/conf/gitolite.conf to change project user/phw/obfsproxy to category Migrated to GitLab
INFO: processing project user/phw/scramblesuit (Philipp's ScrambleSuit repository) in category Users' development repositories (Attic)
INFO: user repository detected, trying to find fork phw/scramblesuit
WARNING: no existing fork found, entering user fork subroutine
WARNING: no matching gitlab project found for user/phw/scramblesuit
INFO: user fork subroutine failed, resuming normal procedure
INFO: searching for projects matching scramblesuit
import gitolite project user/phw/scramblesuit into gitlab legacy/gitolite/user/phw/scramblesuit with desc 'Philipp's ScrambleSuit repository'?^G [Y/n] 
INFO: checking if remote repo https://git.torproject.org/user/phw/scramblesuit exists
INFO: importing gitolite project user/phw/scramblesuit into gitlab legacy/gitolite/user/phw/scramblesuit with desc 'Philipp's ScrambleSuit repository'
INFO: importing project into GitLab
INFO: Successfully connected to https://gitlab.torproject.org
INFO: loading group legacy/gitolite/user/phw
INFO: creating repository scramblesuit (scramblesuit) in namespace legacy/gitolite/user/phw from https://git.torproject.org/user/phw/scramblesuit into https://gitlab.torproject.org/legacy/gitolite/user/phw/scramblesuit
INFO: archiving project
INFO: migrating Gitolite repository https://gitweb.torproject.org/user/phw/scramblesuit.git to GitLab project https://gitlab.torproject.org/legacy/gitolite/user/phw/scramblesuit
INFO: adding entry to rewrite_map /home/anarcat/src/tor/tor-puppet/modules/profile/files/git/gitolite2gitlab.txt
INFO: modifying gitolite.conf to add: "config gitweb.category = Migrated to GitLab"
INFO: rewriting gitolite config /home/anarcat/src/tor/gitolite-admin/conf/gitolite.conf to change project user/phw/scramblesuit to category Migrated to GitLab
[...]

Acute eyes will notice the bell used as a notification mechanism as well in this transcript. A lot of the code is now useless for us, but some, like "commit and push" or is-repo-empty live on in the git module and, of course, the gitlab module has grown some legs along the way. We've also found fun bugs, like a file descriptor exhaustion in bash, among other oddities. The retirement milestone and issue 41215 has a detailed log of the migration, for those curious. This was a challenging project, but it feels nice to have this behind us. This gets rid of 2 of the 4 remaining machines running Debian "old-old-stable", which moves a bit further ahead in our late bullseye upgrades milestone. Full transparency: we tested GPT-3.5, GPT-4, and other large language models to see if they could answer the question "write a set of rewrite rules to redirect GitWeb to GitLab". This has become a standard LLM test for your faithful writer to figure out how good a LLM is at technical responses. None of them gave an accurate, complete, and functional response, for the record. The actual rewrite rules as of this writing follow, for humans that actually like working answers provided by expert humans instead of artificial intelligence which currently seem to be, glorified, mansplaining interns.

git.torproject.org rewrite rules Those rules are relatively simple in that they rewrite a single URL to its equivalent GitLab counterpart in a 1:1 fashion. It relies on the rewrite map mentioned above, of course.

RewriteEngine on
# this RewriteMap connects the gitweb projects to their GitLab
# equivalent
RewriteMap gitolite2gitlab "txt:/etc/apache2/gitolite2gitlab.txt"
# if this becomes a performance bottleneck, convert to a DBM map with:
#
#  $ httxt2dbm -i mapfile.txt -o mapfile.map
#
# and:
#
# RewriteMap mapname "dbm:/etc/apache/mapfile.map"
#
# according to reports lavamind found online, we hit such a
# performance bottleneck only around millions of entries, which is not our case
# those two rules can go away once all the projects are
# migrated to GitLab
#
# this matches the request URI so we can check the RewriteMap
# for a match next
#
# WARNING: this won't match URLs without .git in them, which
# *do* work now. one possibility would be to match the request
# URI (without query string!) with:
#
# /git/(.*)(.git)?/(((branches hooks info objects/).*) git-.* upload-pack receive-pack HEAD config description)?.
#
# I haven't been able to figure out the actual structure of
# those URLs, so it's really hard to figure out the boundaries
# of the project name here. I stopped after pouring around the
# http-backend.c code in git
# itself. https://www.git-scm.com/docs/http-protocol is also
# kind of incomplete and unsatisfying.
RewriteCond % REQUEST_URI  ^/(git/)?(.*).git/.*$
# this makes the RewriteRule match only if there's a match in
# the rewrite map
RewriteCond $ gitolite2gitlab:%2 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(git/)?(.*).git/(.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$2 .git/$3 [R=302,L]
# Fallback everything else to GitLab
RewriteRule (.*) https://gitlab.torproject.org [R=302,L]

gitweb.torproject.org rewrite rules Those are the vastly more complicated GitWeb to GitLab rewrite rules. Note that we say "GitWeb" but we were actually not running GitWeb but cgit, as the former didn't actually scale for us.

RewriteEngine on
# this RewriteMap connects the gitweb projects to their GitLab
# equivalent
RewriteMap gitolite2gitlab "txt:/etc/apache2/gitolite2gitlab.txt"
# special rule to process targets of the old spec.tpo site and
# bring them to the right redirect on the new spec.tpo site. that should turn, for example:
#
# https://gitweb.torproject.org/torspec.git/tree/address-spec.txt
#
# into:
#
# https://spec.torproject.org/address-spec
RewriteRule ^/torspec.git/tree/(.*).txt$ https://spec.torproject.org/$1 [R=302]
# list of endpoints taken from cgit's cmd.c
# those two RewriteCond are necessary because we don't move
# all repositories at once. once the migration is completed,
# they can be removed.
#
# and yes, they are copied all over the place below
#
# create a match for the project name to check if the project
# has been moved to GitLab
RewriteCond % REQUEST_URI  ^/(.*).git(/.*)?$
# this makes the RewriteRule match only if there's a match in
# the rewrite map
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
# main project page, like summary below
RewriteRule ^/(.*).git/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 / [R=302,L]
# summary
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/summary/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 / [R=302,L]
# about
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/about/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 / [R=302,L]
# commit
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond "% QUERY_STRING " "(.*(?:^ &))id=([^&]*)(&.*)?$"
RewriteRule ^/(.*).git/commit/? https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commit/%2 [R=302,L,QSD]
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/commit/? https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commits/HEAD [R=302,L]
# diff, incomplete because can diff arbitrary refs and files in cgit but not in GitLab, hard to parse
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  id=([^&]*)
RewriteRule ^/(.*).git/diff/? https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commit/%1 [R=302,L,QSD]
# patch
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  id=([^&]*)
RewriteRule ^/(.*).git/patch/? https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commit/%1.patch [R=302,L,QSD]
# rawdiff, incomplete because can show only one file diff, which GitLab cannot
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  id=([^&]*)
RewriteRule ^/(.*).git/rawdiff/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commit/%1.diff [R=302,L,QSD]
# log
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  h=([^&]*)
RewriteRule ^/(.*).git/log/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commits/%1 [R=302,L,QSD]
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/log/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commits/HEAD [R=302,L]
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/log(/?.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commits/HEAD$2 [R=302,L]
# atom
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  h=([^&]*)
RewriteRule ^/(.*).git/atom/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commits/%1 [R=302,L,QSD]
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/atom/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/commits/HEAD [R=302,L,QSD]
# refs, incomplete because two pages in GitLab, defaulting to "tags"
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/refs/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/tags [R=302,L]
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  h=([^&]*)
RewriteRule ^/(.*).git/tag/? https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/tags/%1 [R=302,L,QSD]
# tree
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  id=([^&]*)
RewriteRule ^/(.*).git/tree(/?.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/tree/%1$2 [R=302,L,QSD]
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/tree(/?.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/tree/HEAD$2 [R=302,L]
# /-/tree has no good default in GitLab, revert to HEAD which is a good
# approximation (we can't assume "master" here anymore)
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/tree/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/tree/HEAD [R=302,L]
# plain
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteCond % QUERY_STRING  h=([^&]*)
RewriteRule ^/(.*).git/plain(/?.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/raw/%1$2 [R=302,L,QSD]
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/plain(/?.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/raw/HEAD$2 [R=302,L]
# blame: disabled
#RewriteCond % REQUEST_URI  ^/(.*).git/.*$
#RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
#RewriteCond % QUERY_STRING  h=([^&]*)
#RewriteRule ^/(.*).git/blame(/?.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/blame/%1$2 [R=302,L,QSD]
# same default as tree above
#RewriteCond % REQUEST_URI  ^/(.*).git/.*$
#RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
#RewriteRule ^/(.*).git/blame(/?.*)$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/blame/HEAD/$2 [R=302,L]
# stats
RewriteCond % REQUEST_URI  ^/(.*).git/.*$
RewriteCond $ gitolite2gitlab:%1 NOT_FOUND  !NOT_FOUND
RewriteRule ^/(.*).git/stats/?$ https://gitlab.torproject.org/$ gitolite2gitlab:$1 /-/graphs/HEAD [R=302,L]
# still TODO:
# repolist: once migration is complete
#
# cannot be done:
# atom: needs a feed token, user must be logged in
# blob: no direct equivalent
# info: not working on main cgit website?
# ls_cache: not working, irrelevant?
# objects: undocumented?
# snapshot: pattern too hard to match on cgit's side
# special case, we keep a copy of the main index on the archive
RewriteRule ^/?$ https://archive.torproject.org/websites/gitweb.torproject.org.html [R=302,L]
# Fallback: everything else to GitLab
RewriteRule .* https://gitlab.torproject.org [R=302,L]

The reference copy of those is available in our (currently private) Puppet git repository.

Me: Hi everyone, my name s Matt, and I m a mediocre programmer. Everyone: Hi, Matt. Facilitator: Are you an alcoholic, Matt? Me: No, not since I stopped reading Twitter. Facilitator: Then I think you re in the wrong room.

Neither a Borrower Nor a Lender Be If you know anything about Rust, you probably know about the dreaded borrow checker . It s the thing that makes sure you don t have two pieces of code trying to modify the same data at the same time, or using a value when it s no longer valid. While Rust s borrowing semantics allow excellent performance without compromising safety, for us mediocre programmers it gets very complicated, very quickly. So, the moment the compiler wants to start talking about explicit lifetimes , I shut it up by just using owned values instead. It s not that I never borrow anything; I have some situations that I know are borrow-safe for the mediocre programmer (I ll cover those later). But any time I m not sure how things will pan out, I ll go straight for an owned value. For example, if I need to store some text in a struct or enum, it s going straight into a String. I m not going to start thinking about lifetimes and &'a str; I ll leave that for smarter people. Similarly, if I need a list of things, it s a Vec<T> every time no &'b [T] in my structs, thank you very much.

Attack of the Clones Following on from the above, I ve come to not be afraid of .clone(). I scatter them around my code like seeds in a field. Life s too short to spend time trying to figure out who s borrowing what from whom, if I can just give everyone their own thing. There are warnings in the Rust book (and everywhere else) about how a clone can be expensive . While it s true that, yes, making clones of data structures consumes CPU cycles and memory, it very rarely matters. CPU cycles are (usually) plentiful and RAM (usually) relatively cheap. Mediocre programmer mental effort is expensive, and not to be spent on premature optimisation. Also, if you re coming from most any other modern language, Rust is already giving you so much more performance that you re probably ending up ahead of the game, even if you .clone() everything in sight. If, by some miracle, something I write gets so popular that the expense of all those spurious clones becomes a problem, it might make sense to pay someone much smarter than I to figure out how to make the program a zero-copy masterpiece of efficient code. Until then clone early and clone often, I say!

Derive Macros are Powerful Magicks If you start .clone()ing everywhere, pretty quickly you ll be hit with this error:

error[E0599]: no method named  clone  found for struct  Foo  in the current scope

This is because not everything can be cloned, and so if you want your thing to be cloned, you need to implement the method yourself. Well sort of. One of the things that I find absolutely outstanding about Rust is the derive macro . These allow you to put a little marker on a struct or enum, and the compiler will write a bunch of code for you! Clone is one of the available so-called derivable traits , so you add #[derive(Clone)] to your structs, and poof! you can .clone() to your heart s content. But there are other things that are commonly useful, and so I ve got a set of traits that basically all of my data structures derive:

#[derive(Clone, Debug, Default)]
struct Foo  
    // ...
 

Every time I write a struct or enum definition, that line #[derive(Clone, Debug, Default)] goes at the top. The Debug trait allows you to print a debug representation of the data structure, either with the dbg!() macro, or via the :? format in the format!() macro (and anywhere else that takes a format string). Being able to say what exactly is that? comes in handy so often, not having a Debug implementation is like programming with one arm tied behind your Aeron. Meanwhile, the Default trait lets you create an empty instance of your data structure, with all of the fields set to their own default values. This only works if all the fields themselves implement Default, but a lot of standard types do, so it s rare that you ll define a structure that can t have an auto-derived Default. Enums are easily handled too, you just mark one variant as the default:

#[derive(Clone, Debug, Default)]
enum Bar  
    Something(String),
    SomethingElse(i32),
    #[default]   // <== mischief managed
    Nothing,
 

Borrowing is OK, Sometimes While I previously said that I like and usually use owned values, there are a few situations where I know I can borrow without angering the borrow checker gods, and so I m comfortable doing it. The first is when I need to pass a value into a function that only needs to take a little look at the value to decide what to do. For example, if I want to know whether any values in a Vec<u32> are even, I could pass in a Vec, like this:

fn main()  
    let numbers = vec![0u32, 1, 2, 3, 4, 5];
    if has_evens(numbers)  
        println!("EVENS!");
     
 
fn has_evens(numbers: Vec<u32>) -> bool  
    numbers.iter().any( n  n % 2 == 0)
 

Howver, this gets ugly if I m going to use numbers later, like this:

fn main()  
    let numbers = vec![0u32, 1, 2, 3, 4, 5];
    if has_evens(numbers)  
        println!("EVENS!");
     
    // Compiler complains about "value borrowed here after move"
    println!("Sum:  ", numbers.iter().sum::<u32>());
 
fn has_evens(numbers: Vec<u32>) -> bool  
    numbers.iter().any( n  n % 2 == 0)
 

Helpfully, the compiler will suggest I use my old standby, .clone(), to fix this problem. But I know that the borrow checker won t have a problem with lending that Vec<u32> into has_evens() as a borrowed slice, &[u32], like this:

fn main()  
    let numbers = vec![0u32, 1, 2, 3, 4, 5];
    if has_evens(&numbers)  
        println!("EVENS!");
     
 
fn has_evens(numbers: &[u32]) -> bool  
    numbers.iter().any( n  n % 2 == 0)
 

The general rule I ve got is that if I can take advantage of lifetime elision (a fancy term meaning the compiler can figure it out ), I m probably OK. In less fancy terms, as long as the compiler doesn t tell me to put 'a anywhere, I m in the green. On the other hand, the moment the compiler starts using the words explicit lifetime , I nope the heck out of there and start cloning everything in sight. Another example of using lifetime elision is when I m returning the value of a field from a struct or enum. In that case, I can usually get away with returning a borrowed value, knowing that the caller will probably just be taking a peek at that value, and throwing it away before the struct itself goes out of scope. For example:

struct Foo  
    id: u32,
    desc: String,
 
impl Foo  
    fn description(&self) -> &str  
        &self.desc
     
 

Returning a reference from a function is practically always a mortal sin for mediocre programmers, but returning one from a struct method is often OK. In the rare case that the caller does want the reference I return to live for longer, they can always turn it into an owned value themselves, by calling .to_owned().

Avoid the String Tangle Rust has a couple of different types for representing strings String and &str being the ones you see most often. There are good reasons for this, however it complicates method signatures when you just want to take some sort of bunch of text , and don t care so much about the messy details. For example, let s say we have a function that wants to see if the length of the string is even. Using the logic that since we re just taking a peek at the value passed in, our function might take a string reference, &str, like this:

fn is_even_length(s: &str) -> bool  
    s.len() % 2 == 0
 

That seems to work fine, until someone wants to check a formatted string:

fn main()  
    // The compiler complains about "expected  &str , found  String "
    if is_even_length(format!("my string is  ", std::env::args().next().unwrap()))  
        println!("Even length string");
     
 

Since format! returns an owned string, String, rather than a string reference, &str, we ve got a problem. Of course, it s straightforward to turn the String from format!() into a &str (just prefix it with an &). But as mediocre programmers, we can t be expected to remember which sort of string all our functions take and add & wherever it s needed, and having to fix everything when the compiler complains is tedious. The converse can also happen: a method that wants an owned String, and we ve got a &str (say, because we re passing in a string literal, like "Hello, world!"). In this case, we need to use one of the plethora of available turn this into a String mechanisms (.to_string(), .to_owned(), String::from(), and probably a few others I ve forgotten), on the value before we pass it in, which gets ugly real fast. For these reasons, I never take a String or an &str as an argument. Instead, I use the Power of Traits to let callers pass in anything that is, or can be turned into, a string. Let us have some examples. First off, if I would normally use &str as the type, I instead use impl AsRef<str>:

fn is_even_length(s: impl AsRef<str>) -> bool  
    s.as_ref().len() % 2 == 0
 

Note that I had to throw in an extra as_ref() call in there, but now I can call this with either a String or a &str and get an answer. Now, if I want to be given a String (presumably because I plan on taking ownership of the value, say because I m creating a new instance of a struct with it), I use impl Into<String> as my type:

struct Foo  
    id: u32,
    desc: String,
 
impl Foo  
    fn new(id: u32, desc: impl Into<String>) -> Self  
        Self   id, desc: desc.into()  
     
 

We have to call .into() on our desc argument, which makes the struct building a bit uglier, but I d argue that s a small price to pay for being able to call both Foo::new(1, "this is a thing") and Foo::new(2, format!("This is a thing named name ")) without caring what sort of string is involved.

Always Have an Error Enum Rust s error handing mechanism (Results everywhere), along with the quality-of-life sugar surrounding it (like the short-circuit operator, ?), is a delightfully ergonomic approach to error handling. To make life easy for mediocre programmers, I recommend starting every project with an Error enum, that derives thiserror::Error, and using that in every method and function that returns a Result. How you structure your Error type from there is less cut-and-dried, but typically I ll create a separate enum variant for each type of error I want to have a different description. With thiserror, it s easy to then attach those descriptions:

#[derive(Clone, Debug, thiserror::Error)]
enum Error  
    #[error(" 0  caught fire")]
    Combustion(String),
    #[error(" 0  exploded")]
    Explosion(String),
 

I also implement functions to create each error variant, because that allows me to do the Into<String> trick, and can sometimes come in handy when creating errors from other places with .map_err() (more on that later). For example, the impl for the above Error would probably be:

impl Error  
    fn combustion(desc: impl Into<String>) -> Self  
        Self::Combustion(desc.into())
     
    fn explosion(desc: impl Into<String>) -> Self  
        Self::Explosion(desc.into())
     
 

It s a tedious bit of boilerplate, and you can use the thiserror-ext crate s thiserror_ext::Construct derive macro to do the hard work for you, if you like. It, too, knows all about the Into<String> trick.

Banish map_err (well, mostly) The newer mediocre programmer, who is just dipping their toe in the water of Rust, might write file handling code that looks like this:

fn read_u32_from_file(name: impl AsRef<str>) -> Result<u32, Error>  
    let mut f = File::open(name.as_ref())
        .map_err( e  Error::FileOpenError(name.as_ref().to_string(), e))?;
    let mut buf = vec![0u8; 30];
    f.read(&mut buf)
        .map_err( e  Error::ReadError(e))?;
    String::from_utf8(buf)
        .map_err( e  Error::EncodingError(e))?
        .parse::<u32>()
        .map_err( e  Error::ParseError(e))
 

This works great (or it probably does, I haven t actually tested it), but there are a lot of .map_err() calls in there. They take up over half the function, in fact. With the power of the From trait and the magic of the ? operator, we can make this a lot tidier. First off, assume we ve written boilerplate error creation functions (or used thiserror_ext::Construct to do it for us)). That allows us to simplify the file handling portion of the function a bit:

fn read_u32_from_file(name: impl AsRef<str>) -> Result<u32, Error>  
    let mut f = File::open(name.as_ref())
        // We've dropped the  .to_string()  out of here...
        .map_err( e  Error::file_open_error(name.as_ref(), e))?;
    let mut buf = vec![0u8; 30];
    f.read(&mut buf)
        // ... and the explicit parameter passing out of here
        .map_err(Error::read_error)?;
    // ...

If that latter .map_err() call looks weird, without the e and such, it s passing a function-as-closure, which just saves on a few characters typing. Just because we re mediocre, doesn t mean we re not also lazy. Next, if we implement the From trait for the other two errors, we can make the string-handling lines significantly cleaner. First, the trait impl:

impl From<std::string::FromUtf8Error> for Error  
    fn from(e: std::string::FromUtf8Error) -> Self  
        Self::EncodingError(e)
     
 
impl From<std::num::ParseIntError> for Error  
    fn from(e: std::num::ParseIntError) -> Self  
        Self::ParseError(e)
     
 

(Again, this is boilerplate that can be autogenerated, this time by adding a #[from] tag to the variants you want a From impl on, and thiserror will take care of it for you) In any event, no matter how you get the From impls, once you have them, the string-handling code becomes practically error-handling-free:

    Ok(
        String::from_utf8(buf)?
            .parse::<u32>()?
    )

The ? operator will automatically convert the error from the types returned from each method into the return error type, using From. The only tiny downside to this is that the ? at the end strips the Result, and so we ve got to wrap the returned value in Ok() to turn it back into a Result for returning. But I think that s a small price to pay for the removal of those .map_err() calls. In many cases, my coding process involves just putting a ? after every call that returns a Result, and adding a new Error variant whenever the compiler complains about not being able to convert some new error type. It s practically zero effort outstanding outcome for the mediocre programmer.

Just Because You re Mediocre, Doesn t Mean You Can t Get Better To finish off, I d like to point out that mediocrity doesn t imply shoddy work, nor does it mean that you shouldn t keep learning and improving your craft. One book that I ve recently found extremely helpful is Effective Rust, by David Drysdale. The author has very kindly put it up to read online, but buying a (paper or ebook) copy would no doubt be appreciated. The thing about this book, for me, is that it is very readable, even by us mediocre programmers. The sections are written in a way that really clicked with me. Some aspects of Rust that I d had trouble understanding for a long time such as lifetimes and the borrow checker, and particularly lifetime elision actually made sense after I d read the appropriate sections.

Finally, a Quick Beg I m currently subsisting on the kindness of strangers, so if you found something useful (or entertaining) in this post, why not buy me a refreshing beverage? It helps to know that people like what I m doing, and helps keep me from having to sell my soul to a private equity firm.

There was no way of telling when the threshold would be reached. Perhaps not for hours, and perhaps the next moment. Biron remained standing helplessly, flashlight held loosely in his damp hands. Half an hour before, the visiphone had awakened him, and he had been at peace then. Now he knew he was going to die. Biron didn't want to die, but he was penned in hopelessly, and there was no place to hide.

git clone https://gitlab.com/gsasl/libntlm.git
cd libntlm
git checkout v1.8
./bootstrap
./configure
make distcheck
gpg -b libntlm-1.8.tar.gz

make srcdist
gpg -b libntlm-1.8-src.tar.gz

91de864224913b9493c7a6cec2890e6eded3610d34c3d983132823de348ec2ca  libntlm-1.8-src.tar.gz
ce6569a47a21173ba69c990965f73eb82d9a093eb871f935ab64ee13df47fda1  libntlm-1.8.tar.gz

podman run -it --rm ubuntu:22.04
apt-get update
apt-get install -y --no-install-recommends autoconf automake libtool make git ca-certificates
git clone https://gitlab.com/gsasl/libntlm.git
cd libntlm
git checkout v1.8
./bootstrap
./configure
make dist srcdist
sha256sum libntlm-*.tar.gz

podman run -it --rm almalinux:8
dnf update -y
dnf install -y make wget gcc
wget https://download.savannah.nongnu.org/releases/libntlm/libntlm-1.8.tar.gz
tar xfa libntlm-1.8.tar.gz
cd libntlm-1.8
./configure
make dist
sha256sum libntlm-1.8.tar.gz

podman run -it --rm debian:11
apt-get update
apt-get install -y --no-install-recommends make git ca-certificates
git clone https://gitlab.com/gsasl/libntlm.git
cd libntlm
git checkout v1.8
make -f cfg.mk srcdist
sha256sum libntlm-1.8-src.tar.gz 

podman run -it --rm docker.io/kpengboy/trisquel:11.0
apt-get update
apt-get install -y --no-install-recommends autoconf automake libtool make wget git ca-certificates
wget https://download.savannah.nongnu.org/releases/libntlm/libntlm-1.8-src.tar.gz
tar xfa libntlm-1.8-src.tar.gz
cd libntlm-v1.8
./bootstrap
./configure
make dist
sha256sum libntlm-1.8.tar.gz

git archive --prefix=libntlm-v1.8/ -o libntlm-1.8-src.tar.gz HEAD

1. Arch Linux minimal container userland now 100% reproducible
2. Validating Debian s build infrastructure after the XZ backdoor
3. Making Fedora Linux (more) reproducible
4. Increasing Trust in the Open Source Supply Chain with Reproducible Builds and Functional Package Management
5. Software and source code identification with GNU Guix and reproducible builds
6. Two new Rust-based tools for post-processing determinism
7. Distribution work
8. Mailing list highlights
9. Website updates
10. Delta chat clients now reproducible
11. diffoscope updates
12. Upstream patches
13. Reproducibility testing framework

Arch Linux minimal container userland now 100% reproducible In remarkable news, Reproducible builds developer kpcyrd reported that that the Arch Linux minimal container userland is now 100% reproducible after work by developers dvzv and Foxboron on the one remaining package. This represents a real world , widely-used Linux distribution being reproducible. Their post, which kpcyrd suffixed with the question now what? , continues on to outline some potential next steps, including validating whether the container image itself could be reproduced bit-for-bit. The post, which was itself a followup for an Arch Linux update earlier in the month, generated a significant number of replies.

Validating Debian s build infrastructure after the XZ backdoor From our mailing list this month, Vagrant Cascadian wrote about being asked about trying to perform concrete reproducibility checks for recent Debian security updates, in an attempt to gain some confidence about Debian s build infrastructure given that they performed builds in environments running the high-profile XZ vulnerability. Vagrant reports (with some caveats):

So far, I have not found any reproducibility issues; everything I tested I was able to get to build bit-for-bit identical with what is in the Debian archive.

That is to say, reproducibility testing permitted Vagrant and Debian to claim with some confidence that builds performed when this vulnerable version of XZ was installed were not interfered with.

Making Fedora Linux (more) reproducible In March, Davide Cavalca gave a talk at the 2024 Southern California Linux Expo (aka SCALE 21x) about the ongoing effort to make the Fedora Linux distribution reproducible. Documented in more detail on Fedora s website, the talk touched on topics such as the specifics of implementing reproducible builds in Fedora, the challenges encountered, the current status and what s coming next. (YouTube video)

Increasing Trust in the Open Source Supply Chain with Reproducible Builds and Functional Package Management Julien Malka published a brief but interesting paper in the HAL open archive on Increasing Trust in the Open Source Supply Chain with Reproducible Builds and Functional Package Management:

Functional package managers (FPMs) and reproducible builds (R-B) are technologies and methodologies that are conceptually very different from the traditional software deployment model, and that have promising properties for software supply chain security. This thesis aims to evaluate the impact of FPMs and R-B on the security of the software supply chain and propose improvements to the FPM model to further improve trust in the open source supply chain. PDF

Julien s paper poses a number of research questions on how the model of distributions such as GNU Guix and NixOS can be leveraged to further improve the safety of the software supply chain , etc.

Software and source code identification with GNU Guix and reproducible builds In a long line of commendably detailed blog posts, Ludovic Court s, Maxim Cournoyer, Jan Nieuwenhuizen and Simon Tournier have together published two interesting posts on the GNU Guix blog this month. In early March, Ludovic Court s, Maxim Cournoyer, Jan Nieuwenhuizen and Simon Tournier wrote about software and source code identification and how that might be performed using Guix, rhetorically posing the questions: What does it take to identify software ? How can we tell what software is running on a machine to determine, for example, what security vulnerabilities might affect it? Later in the month, Ludovic Court s wrote a solo post describing adventures on the quest for long-term reproducible deployment. Ludovic s post touches on GNU Guix s aim to support time travel , the ability to reliably (and reproducibly) revert to an earlier point in time, employing the iconic image of Harold Lloyd hanging off the clock in Safety Last! (1925) to poetically illustrate both the slapstick nature of current modern technology and the gymnastics required to navigate hazards of our own making.

Two new Rust-based tools for post-processing determinism Zbigniew J drzejewski-Szmek announced add-determinism, a work-in-progress reimplementation of the Reproducible Builds project s own strip-nondeterminism tool in the Rust programming language, intended to be used as a post-processor in RPM-based distributions such as Fedora In addition, Yossi Kreinin published a blog post titled refix: fast, debuggable, reproducible builds that describes a tool that post-processes binaries in such a way that they are still debuggable with gdb, etc.. Yossi post details the motivation and techniques behind the (fast) performance of the tool.

Distribution work In Debian this month, since the testing framework no longer varies the build path, James Addison performed a bulk downgrade of the bug severity for issues filed with a level of normal to a new level of wishlist. In addition, 28 reviews of Debian packages were added, 38 were updated and 23 were removed this month adding to ever-growing knowledge about identified issues. As part of this effort, a number of issue types were updated, including Chris Lamb adding a new ocaml_include_directories toolchain issue [ ] and James Addison adding a new filesystem_order_in_java_jar_manifest_mf_include_resource issue [ ] and updating the random_uuid_in_notebooks_generated_by_nbsphinx to reference a relevant discussion thread [ ]. In addition, Roland Clobus posted his 24th status update of reproducible Debian ISO images. Roland highlights that the images for Debian unstable often cannot be generated due to changes in that distribution related to the 64-bit time_t transition. Lastly, Bernhard M. Wiedemann posted another monthly update for his reproducibility work in openSUSE.

Mailing list highlights Elsewhere on our mailing list this month:

• Alexander Railean of Siemens asked the list to aid in understanding how one can independently verify the reproducibility of Java projects from the Maven Central repository. Having explored those repositories, Alexander could not find examples where the buildinfo file was present. Arnout Engelen responded with some details.
• Fay Stegerman resuscitated a long-dormant thread to report that she added support in her diff-zip-meta.py tool to expose extra timestamps embedded in .zip and .apk metadata.

Website updates There were made a number of improvements to our website this month, including:

• Pol Dellaiera noticed the frequent need to correctly cite the website itself in academic work. To facilitate easier citation across multiple formats, Pol contributed a Citation File Format (CIF) file. As a result, an export in BibTeX format is now available in the Academic Publications section. Pol encourages community contributions to further refine the CITATION.cff file. Pol also added an substantial new section to the buy in page documenting the role of Software Bill of Materials (SBOMs) and ephemeral development environments. [ ][ ]
• Bernhard M. Wiedemann added a new commandments page to the documentation [ ][ ] and fixed some incorrect YAML elsewhere on the site [ ].
• Chris Lamb add three recent academic papers to the publications page of the website. [ ]
• Mattia Rizzolo and Holger Levsen collaborated to add Infomaniak as a sponsor of amd64 virtual machines. [ ][ ][ ]
• Roland Clobus updated the stable outputs page, dropping version numbers from Python documentation pages [ ] and noting that Python s set data structure is also affected by the PYTHONHASHSEED functionality. [ ]

Delta chat clients now reproducible Delta Chat, an open source messaging application that can work over email, announced this month that the Rust-based core library underlying Delta chat application is now reproducible.

diffoscope diffoscope is our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues. This month, Chris Lamb made a number of changes such as uploading versions 259, 260 and 261 to Debian and made the following additional changes:

• New features:
  • Add support for the zipdetails tool from the Perl distribution. Thanks to Fay Stegerman and Larry Doolittle et al. for the pointer and thread about this tool. [ ]
• Bug fixes:
  • Don t identify Redis database dumps as GNU R database files based simply on their filename. [ ]
  • Add a missing call to File.recognizes so we actually perform the filename check for GNU R data files. [ ]
  • Don t crash if we encounter an .rdb file without an equivalent .rdx file. (#1066991)
  • Correctly check for 7z being available and not lz4 when testing 7z. [ ]
  • Prevent a traceback when comparing a contentful .pyc file with an empty one. [ ]
• Testsuite improvements:
  • Fix .epub tests after supporting the new zipdetails tool. [ ]
  • Don t use parenthesis within test skipping messages, as PyTest adds its own parenthesis. [ ]
  • Factor out Python version checking in test_zip.py. [ ]
  • Skip some Zip-related tests under Python 3.10.14, as a potential regression may have been backported to the 3.10.x series. [ ]
  • Actually test 7z support in the test_7z set of tests, not the lz4 functionality. (Closes: reproducible-builds/diffoscope#359). [ ]

In addition, Fay Stegerman updated diffoscope s monkey patch for supporting the unusual Mozilla ZIP file format after Python s zipfile module changed to detect potentially insecure overlapping entries within .zip files. (#362) Chris Lamb also updated the trydiffoscope command line client, dropping a build-dependency on the deprecated python3-distutils package to fix Debian bug #1065988 [ ], taking a moment to also refresh the packaging to the latest Debian standards [ ]. Finally, Vagrant Cascadian submitted an update for diffoscope version 260 in GNU Guix. [ ]

Upstream patches This month, we wrote a large number of patches, including:

• Bernhard M. Wiedemann:
  • helm (SSL-related build failure)
  • java-21-openjdk (parallelism)
  • libressl (SSL-related build failure)
  • nfdump (date issue)
  • python-django-q (avoid stuck build)
  • python-smart-open (fails to build on single-CPU machines)
  • python-stdnum (fails to build in 2039)
  • python-yarl (regression)
  • qemu (build failure)
  • rabbitmq-java-client (with Fridrich Strba; Maven timestamp issue)
  • rmw (build fails in 2038)
  • warewulf (with Egbert Eich; cpio modification time and inode issue)
  • wxWidgets (fails to build in 2038)
• Chris Lamb:
  • #1066042 filed against python-quantities.
  • #1066083 filed against gnome-maps.
  • #1066084 filed against tox.
  • #1066085 filed against q2cli.
  • #1067098 filed against mpl-sphinx-theme.
  • #1067099 filed against woof-doom.
  • #1067100 filed against bochs.
  • #1067101 filed against storm-lang.
  • #1067102 filed against librsvg.
  • #1067218 filed against gretl.
  • #1067483 filed against postfix.
  • #1067484 filed against node-function-bind.
  • #1067485 filed against python-pysaml2.
  • #1067947 filed against golang-github-stvp-tempredis.
• James Addison:
  • #1065124 filed against matplotlib.
  • #1066014 filed against pathos.
  • #1066016 filed against rdflib.
  • #1066017 filed against xonsh.
  • #1066045 filed against maven-bundle-plugin. (This patch was then uploaded by Mattia Rizzollo.)
• Ji Techet:
  • geany (toolchain-related issue for glfw)

Bernhard M. Wiedemann used reproducibility-tooling to detect and fix packages that added changes in their %check section, thus failing when built with the --no-checks option. Only half of all openSUSE packages were tested so far, but a large number of bugs were filed, including ones against caddy, exiv2, gnome-disk-utility, grisbi, gsl, itinerary, kosmindoormap, libQuotient, med-tools, plasma6-disks, pspp, python-pypuppetdb, python-urlextract, rsync, vagrant-libvirt and xsimd. Similarly, Jean-Pierre De Jesus DIAZ employed reproducible builds techniques in order to test a proposed refactor of the ath9k-htc-firmware package. As the change produced bit-for-bit identical binaries to the previously shipped pre-built binaries:

I don t have the hardware to test this firmware, but the build produces the same hashes for the firmware so it s safe to say that the firmware should keep working.

Reproducibility testing framework The Reproducible Builds project operates a comprehensive testing framework running primarily at tests.reproducible-builds.org in order to check packages and other artifacts for reproducibility. In March, an enormous number of changes were made by Holger Levsen:

• Debian-related changes:
  • Sleep less after a so-called 404 package state has occurred. [ ]
  • Schedule package builds more often. [ ][ ]
  • Regenerate all our HTML indexes every hour, but only every 12h for the released suites. [ ]
  • Create and update unstable and experimental base systems on armhf again. [ ][ ]
  • Don t reschedule so many depwait packages due to the current size of the i386 architecture queue. [ ]
  • Redefine our scheduling thresholds and amounts. [ ]
  • Schedule untested packages with a higher priority, otherwise slow architectures cannot keep up with the experimental distribution growing. [ ]
  • Only create the stats_buildinfo.png graph once per day. [ ][ ]
  • Reproducible Debian dashboard: refactoring, update several more static stats only every 12h. [ ]
  • Document how to use systemctl with new systemd-based services. [ ]
  • Temporarily disable armhf and i386 continuous integration tests in order to get some stability back. [ ]
  • Use the deb.debian.org CDN everywhere. [ ]
  • Remove the rsyslog logging facility on bookworm systems. [ ]
  • Add zst to the list of packages which are false-positive diskspace issues. [ ]
  • Detect failures to bootstrap Debian base systems. [ ]
• Arch Linux-related changes:
  • Temporarily disable builds because the pacman package manager is broken. [ ][ ]
  • Split reproducible_html_live_status and split the scheduling timing . [ ][ ][ ]
  • Improve handling when database is locked. [ ][ ]
• Misc changes:
  • Show failed services that require manual cleanup. [ ][ ]
  • Integrate two new Infomaniak nodes. [ ][ ][ ][ ]
  • Improve IRC notifications for artifacts. [ ]
  • Run diffoscope in different systemd slices. [ ]
  • Run the node health check more often, as it can now repair some issues. [ ][ ]
  • Also include the string Bot in the userAgent for Git. (Re: #929013). [ ]
  • Document increased tmpfs size on our OUSL nodes. [ ]
  • Disable memory account for the reproducible_build service. [ ][ ]
  • Allow 10 times as many open files for the Jenkins service. [ ]
  • Set OOMPolicy=continue and OOMScoreAdjust=-1000 for both the Jenkins and the reproducible_build service. [ ]

Mattia Rizzolo also made the following changes:

• Debian-related changes:
  • Define a systemd slice to group all relevant services. [ ][ ]
  • Add a bunch of quotes in scripts to assuage the shellcheck tool. [ ]
  • Add stats on how many packages have been built today so far. [ ]
  • Instruct systemd-run to handle diffoscope s exit codes specially. [ ]
  • Prefer the pgrep tool over grepping the output of ps. [ ]
  • Re-enable a couple of i386 and armhf architecture builders. [ ][ ]
  • Fix some stylistic issues flagged by the Python flake8 tool. [ ]
  • Cease scheduling Debian unstable and experimental on the armhf architecture due to the time_t transition. [ ]
  • Start a few more i386 & armhf workers. [ ][ ][ ]
  • Temporarly skip pbuilder updates in the unstable distribution, but only on the armhf architecture. [ ]
• Other changes:
  • Perform some large-scale refactoring on how the systemd service operates. [ ][ ]
  • Move the list of workers into a separate file so it s accessible to a number of scripts. [ ]
  • Refactor the powercycle_x86_nodes.py script to use the new IONOS API and its new Python bindings. [ ]
  • Also fix nph-logwatch after the worker changes. [ ]
  • Do not install the stunnel tool anymore, it shouldn t be needed by anything anymore. [ ]
  • Move temporary directories related to Arch Linux into a single directory for clarity. [ ]
  • Update the arm64 architecture host keys. [ ]
  • Use a common Postfix configuration. [ ]

The following changes were also made by:

• Jan-Benedict Glaw:
  • Initial work to clean up a messy NetBSD-related script. [ ][ ]
• Roland Clobus:
  • Show the installer log if the installer fails to build. [ ]
  • Avoid the minus character (i.e. -) in a variable in order to allow for tags in openQA. [ ]
  • Update the schedule of Debian live image builds. [ ]
• Vagrant Cascadian:
  • Maintenance on the virt* nodes is completed so bring them back online. [ ]
  • Use the fully qualified domain name in configuration. [ ]

Node maintenance was also performed by Holger Levsen, Mattia Rizzolo [ ][ ] and Vagrant Cascadian [ ][ ][ ][ ]

---

If you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. However, you can get in touch with us via:

• IRC: #reproducible-builds on irc.oftc.net.
• Twitter: @ReproBuilds
• Mastodon: @reproducible_builds@fosstodon.org
• Mailing list: rb-general@lists.reproducible-builds.org

Prelude to an Adventure Our story begins back in March 2008. I was working at Engine Yard (EY), a now largely-forgotten Rails-focused hosting company, which pioneered several advances in Rails application deployment. Probably EY s greatest claim to lasting fame is that they helped launch a little code hosting platform you might have heard of, by providing them free infrastructure when they were little more than a glimmer in the Internet s eye. I am, of course, talking about everyone s favourite Microsoft product: GitHub. Since GitHub was in the right place, at the right time, with a compelling product offering, they quickly started to gain traction, and grow their userbase. With growth comes challenges, amongst them the one we re focusing on today: SSH login times. Then, as now, GitHub provided SSH access to the git repos they hosted, by SSHing to git@github.com with publickey authentication. They were using the standard way that everyone manages SSH keys: the ~/.ssh/authorized_keys file, and that became a problem as the number of keys started to grow. The way that SSH uses this file is that, when a user connects and asks for publickey authentication, SSH opens the ~/.ssh/authorized_keys file and scans all of the keys listed in it, looking for a key which matches the key that the user presented. This linear search is normally not a huge problem, because nobody in their right mind puts more than a few keys in their ~/.ssh/authorized_keys, right?

Of course, as a popular, rapidly-growing service, GitHub was gaining users at a fair clip, to the point that the one big file that stored all the SSH keys was starting to visibly impact SSH login times. This problem was also not going to get any better by itself. Something Had To Be Done. EY management was keen on making sure GitHub ran well, and so despite it not really being a hosting problem, they were willing to help fix this problem. For some reason, the late, great, Ezra Zygmuntowitz pointed GitHub in my direction, and let me take the time to really get into the problem with the GitHub team. After examining a variety of different possible solutions, we came to the conclusion that the least-worst option was to patch OpenSSH to lookup keys in a MySQL database, indexed on the key fingerprint. We didn t take this decision on a whim it wasn t a case of yeah, sure, let s just hack around with OpenSSH, what could possibly go wrong? . We knew it was potentially catastrophic if things went sideways, so you can imagine how much worse the other options available were. Ensuring that this wouldn t compromise security was a lot of the effort that went into the change. In the end, though, we rolled it out in early April, and lo! SSH logins were fast, and we were pretty sure we wouldn t have to worry about this problem for a long time to come. Normally, you d think patching OpenSSH to make mass SSH logins super fast would be a good story on its own. But no, this is just the opening scene.

Chekov s Gun Makes its Appearance Fast forward a little under a month, to the first few days of May 2008. I get a message from one of the GitHub team, saying that somehow users were able to access other users repos over SSH. Naturally, as we d recently rolled out the OpenSSH patch, which touched this very thing, the code I d written was suspect number one, so I was called in to help.

They're called The Usual Suspects for a reason, but sometimes, it really is Keyser S ze

Eventually, after more than a little debugging, we discovered that, somehow, there were two users with keys that had the same key fingerprint. This absolutely shouldn t happen it s a bit like winning the lottery twice in a row¹ unless the users had somehow shared their keys with each other, of course. Still, it was worth investigating, just in case it was a web application bug, so the GitHub team reached out to the users impacted, to try and figure out what was going on. The users professed no knowledge of each other, neither admitted to publicising their key, and couldn t offer any explanation as to how the other person could possibly have gotten their key. Then things went from weird to what the ? . Because another pair of users showed up, sharing a key fingerprint but it was a different shared key fingerprint. The odds now have gone from winning the lottery multiple times in a row to as close to this literally cannot happen as makes no difference.

Once we were really, really confident that the OpenSSH patch wasn t the cause of the problem, my involvement in the problem basically ended. I wasn t a GitHub employee, and EY had plenty of other customers who needed my help, so I wasn t able to stay deeply involved in the on-going investigation of The Mystery of the Duplicate Keys. However, the GitHub team did keep talking to the users involved, and managed to determine the only apparent common factor was that all the users claimed to be using Debian or Ubuntu systems, which was where their SSH keys would have been generated. That was as far as the investigation had really gotten, when along came May 13, 2008.

Chekov s Gun Goes Off With the publication of DSA-1571-1, everything suddenly became clear. Through a well-meaning but ultimately disasterous cleanup of OpenSSL s randomness generation code, the Debian maintainer had inadvertently reduced the number of possible keys that could be generated by a given user from bazillions to a little over 32,000. With so many people signing up to GitHub some of them no doubt following best practice and freshly generating a separate key it s unsurprising that some collisions occurred. You can imagine the sense of oooooooh, so that s what s going on! that rippled out once the issue was understood. I was mostly glad that we had conclusive evidence that my OpenSSH patch wasn t at fault, little knowing how much more contact I was to have with Debian weak keys in the future, running a huge store of known-compromised keys and using them to find misbehaving Certificate Authorities, amongst other things.

Lessons Learned While I ve not found a description of exactly when and how Luciano Bello discovered the vulnerability that became CVE-2008-0166, I presume he first came across it some time before it was disclosed likely before GitHub tripped over it. The stable Debian release that included the vulnerable code had been released a year earlier, so there was plenty of time for Luciano to have discovered key collisions and go hmm, I wonder what s going on here? , then keep digging until the solution presented itself. The thought hmm, that s odd , followed by intense investigation, leading to the discovery of a major flaw is also what ultimately brought down the recent XZ backdoor. The critical part of that sequence is the ability to do that intense investigation, though. When I reflect on my brush with the Debian weak keys vulnerability, what sticks out to me is the fact that I didn t do the deep investigation. I wonder if Luciano hadn t found it, how long it might have been before it was found. The GitHub team would have continued investigating, presumably, and perhaps they (or I) would have eventually dug deep enough to find it. But we were all super busy myself, working support tickets at EY, and GitHub feverishly building features and fighting the fires in their rapidly-growing service. As it was, Luciano was able to take the time to dig in and find out what was happening, but just like the XZ backdoor, I feel like we, as an industry, got a bit lucky that someone with the skills, time, and energy was on hand at the right time to make a huge difference. It s a luxury to be able to take the time to really dig into a problem, and it s a luxury that most of us rarely have. Perhaps an understated takeaway is that somehow we all need to wrestle back some time to follow our hunches and really dig into the things that make us go hmm .

Support My Hunches If you d like to help me be able to do intense investigations of mysterious software phenomena, you can shout me a refreshing beverage on ko-fi.

---

1. the odds are actually probably more like winning the lottery about twenty times in a row. The numbers involved are staggeringly huge, so it s easiest to just approximate it as really, really unlikely .

• Andreas Tille [Interview]
• Sruthi Chandran [this document]

I usually talk about me whenever I am talking about answering the question who am I, I usually say like I am a librarian turned free software enthusiast and a Debian Developer. So I had no technical background and I learned, I was introduced to free software through my husband and then I learned Debian packaging, and eventually I became a Debian Developer. So I always give my example to people who say I am not technically inclined, I don't have technical background so I can't contribute to free software. So yeah, that's what I refer to myself.

Okay, so let me start from my initial days in Debian. I started contributing to Debian, my first contribution was a Tibetan font. We went to a Tibetan place and they were saying they didn't have a font in Linux. So that's how I started contributing. Then I moved on to Ruby packages, then I have some JavaScript and Go packages, all dependencies of GitLab. So I was involved with maintaining GitLab for some time, now I'm not very active there. But yeah, so GitLab was the main package I was contributing to since I contributed since 2016 to maybe like 2020 or something. Later I have come [over to] packaging. Now I am part of some of the teams, delegated teams, like community team and outreach team, as well as the Debconf committee. And the biggest, I think, my activity in Debian, I would say is organizing Debconf 2023. So it was a great experience and yeah, so that's my story in Debian.

Okay, let me first think about it. For candidacy, I can start with diversity is one point I started expressing from the first time I contested for DPL. But to be honest, that's the main point I want to bring.

So for diversity, if you could break down your thoughts on diversity and make them, [about] your three points including diversity.

So in addition to, eventually when starting it was just diversity. Now I have like a bit more ideas, like community, like I want to be a leader for the Debian community. More than, I don't know, maybe people may not agree, but I would say I want to be a leader of Debian community rather than a Debian operating system. I connect to community more and third point I would say.

Okay. So I, like, I am very happy with the structure of Debian and how things work in Debian. Like you can do almost a lot of things, like almost all things without being a DPL. Whatever change you want to bring about or whatever you want to do, you can do without being a DPL. Anyone, like every DD has the same rights. Only things I feel [the] DPL has hold on are mainly the budget or the funding part, which like, that's where they do the decision making part. And then comes like, and one advantage of DPL driving some idea is that somehow people tend to listen to that with more, like, tend to give more attention to what DPL is saying rather than a normal DD. So I wanted to, like, I have answered some of the questions on how to, how I plan to do the financial budgeting part, how I want to handle, like, and the other thing is using the extra attention that I get as a DPL, I would like to obviously start with the diversity aspect in Debian. And yeah, like, I, what I want to do is not, like, be a leader and say, like, take Debian to one direction where I want to go, but I would rather take suggestions and inputs from the whole community and go about with that. So yes, that's what I would say.

Vim.

Vim, wholeheartedly team Vim?

Yes.

Great. Well, this was made in Vim, all the text for this.

So, like, since you mentioned extra data, I'll give my example, like, it's just a fun note, when I started contributing to Debian, as I mentioned, I didn't have any knowledge about free software, like Debian, and I was not used to even using Linux. So, and I didn't have experience with these text editors. So, when I started contributing, I used to do the editing part using gedit. So, that's how I started. Eventually, I moved to Nano, and once I reached Vim, I didn't move on.

Okay. So, Debian, as we all know, is referred to as the universal operating system without, like, it is said for a reason. We have hundreds and hundreds of operating systems, like Linux, distributions based on Debian. So, I believe Debian, like even now, Debian has good influence on the, at least on the Linux or Linux ecosystem. So, what we implement in Debian has, like, is going to affect quite a lot of, like, a very good percentage of people using Linux. So, yes. So, I think Debian is one of the leading Linux distributions. And I think in 10 years, we should be able to reach a position, like, where we are not, like, even now, like, even these many years after having Linux, we face a lot of problems in newer and newer hardware coming up and installing on them is a big problem. Like, firmwares and all those things are getting more and more complicated. Like, it should be getting simpler, but it's getting more and more complicated. So, I, one thing I would imagine, like, I don't know if we will ever reach there, but I would imagine that eventually with the Debian, we should be able to have some, at least a few of the hardware developers or hardware producers have Debian pre-installed and those kind of things. Like, not, like, become, I'm not saying it's all, it's also available right now. What I'm saying is that it becomes prominent enough to be opted as, like, default distro.

Okay. So, I started to contribute in 2016, and I was part of the team doing GitLab packaging, and we did have a lot of training workshops and those kind of things within India. And I was, like, I had interacted with some of the Indian DDs, but I never got, like, even through chat or mail. I didn't have a lot of interaction with the rest of the world, DDs. And the 2019 Debconf changed my whole perspective about Debian. Before that, I wasn't, like, even, I was interested in free software. I was doing the technical stuff and all. But after DebConf, my whole idea has been, like, my focus changed to the community. Debian community is a very welcoming, very interesting community to be with. And so, I believe that, like, 2019 DebConf was a for me. And that kept, from 2019, my focus has been to how to support, like, how, I moved to the community part of Debian from there. Then in 2020 I became part of the community team, and, like, I started being part of other teams. So, these, I would say, the Debian community is the one, like, aspect of Debian that keeps me whole, keeps me held on to the Debian ecosystem as a whole.

I think I may sound like a broken record or something.

No, no.

Again, I would say the Debian community, like, it's the people who makes Debian, that makes Debian special. Like, apart from that, if I say, I would say I'm very, like, one part of Debian that makes me very happy is the, how the governing system of Debian works, the Debian constitution and all those things, like, it's a very unique thing for Debian. And, and it's like, when people say you can't work without a proper, like, establishment or even somebody deciding everything for you, it's difficult. When people say, like, we have been, Debian has been proving it for quite a long time now, that it's possible. So, so that's one thing I believe, like, that's one unique point. And I am very proud about that.

So, I think where Debian is failing now is getting new people into Debian. Like, I don't remember, like, exactly the answer. But I remember hearing someone mention, like, the average age of a Debian Developer is, like, above 40 or 45 or something, like, exact age, I don't remember. But it's like, Debian is getting old. Like, the people in Debian are getting old and we are not getting enough of new people into Debian. And that's very important to have people, like, new people coming up. Otherwise, eventually, like, after a few years, nobody, like, we won't have enough people to take the project forward. So, yeah, I believe that is where we need to work on. We are doing some efforts, like, being part of GSOC or outreachy and having maybe other events, like, local events. Like, we used to have a lot of Debian packaging workshops in India. And those kind of, I think, in Brazil and all, they all have, like, local communities are doing. But we are not very successful in retaining the people who maybe come and try out things. But we are not very good at retaining the people, like, retaining people who come. So, we need to work on those things. Right now, I don't have a solid answer for that. But one thing, like, I was thinking about is, like, having a Debian specific outreach project, wherein the focus will be about the Debian, like, starting will be more on, like, usually what happens in GSOC and outreach is that people come, have the, do the contributions, and they go back. Like, they don't have that connection with the Debian, like, Debian community or Debian project. So, what I envision with these, the Debian outreach, the Debian specific outreach is that we have some part of the internship, like, even before starting the internship, we have some sessions and, like, with the people in Debian having, like, getting them introduced to the Debian philosophy and Debian community and Debian, how Debian works. And those things, we focus on that. And then we move on to the technical internship parts. So, I believe this could do some good in having, like, when you have people you can connect to, you tend to stay back in a project mode. When you feel something more than, like, right now, we have so many technical stuff to do, like, the choice for a college student is endless. So, if they want, if they stay back for something, like, maybe for Debian, I would say, we need to have them connected to the Debian project before we go into technical parts. Like, technical parts, like, there are other things as well, where they can go and do the technical part, but, like, they can come here, like, yeah. So, that's what I was saying. Focused outreach projects is one thing. That's just one. That's not enough. We need more of, like, more ideas to have more new people come up. And I'm very happy with, like, the DebConf thing. We tend to get more and more people from the places where we have a DebConf. Brazil is an example. After the Debconf, they have quite a good improvement on Debian contributors. And I think in India also, it did give a good result. Like, we have more people contributing and staying back and those things. So, yeah. So, these were the things I would say, like, we can do to improve.

Okay. Like, right now, what comes to my mind is the free software licenses parts. Like, we have a lot of free software licenses, and there are non-free software licenses. But currently, I feel free software is having a big problem in enforcing these licenses. Like, there are, there may be big corporations or like some people who take up the whole, the code and may not follow the whole, for example, the GPL licenses. Like, we don't know how much of those, how much of the free softwares are used in the bigger things. Yeah, I agree. There are a lot of corporations who are afraid to touch free software. But there would be good amount of free software, free work that converts into property, things violating the free software licenses and those things. And we do not have the kind of like, we have SFLC, SFC, etc. But still, we do not have the ability to go behind and trace and implement the licenses. So, enforce those licenses and bring people who are violating the licenses forward and those kind of things is challenging because one thing is it takes time, like, and most importantly, money is required for the legal stuff. And not always people who like people who make small software, or maybe big, but they may not have the kind of time and money to have these things enforced. So, that's a big challenge free software is facing, especially in our current scenario. I feel we are having those, like, we need to find ways how we can get it sorted. I don't have an answer right now what to do. But this is a challenge I felt like and Debian's part in that. Yeah, as I said, I don't have a solution for that. But the Debian, so DFSG and Debian sticking on to the free software licenses is a good support, I think.

Not really, like, I am happy, like, I think I was able to answer the questions. And yeah, I would say who is watching. I won't say like, I'm the best DPL candidate, you can't have a better one or something. I stand for a reason. And if you believe in that, or the Debian community and Debian diversity, and those kinds of things, if you believe it, I hope you would be interested, like, you would want to vote for me. That's it. Like, I'm not, I'll make it very clear. I'm not doing a technical leadership part here. So, those, I can't convince people who want technical leadership to vote for me. But I would say people who connect with me, I hope they vote for me.

$ sudo apt update
$ sudo apt install flatpak

$ flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo

$ which -s gnome-software  && sudo apt install gnome-software-plugin-flatpak
$ which -s plasma-discover && sudo apt install plasma-discover-backend-flatpak

$ dpkg -l   grep xdg-desktop-portal   awk ' print $2 '
xdg-desktop-portal
xdg-desktop-portal-gnome
xdg-desktop-portal-gtk

Flatpak commands are run system-wide by default. If you are installing applications for day-to-day usage, it is recommended to stick with this default behavior.

$ flatpak install flathub org.mozilla.firefox

$ flatpak run org.mozilla.firefox

• from ~/.mozilla/ -- where the Firefox Debian package stores its data
• into ~/.var/app/org.mozilla.firefox/.mozilla/ -- where the Firefox Flatpak app stores its data

# BEWARE! Below I'm erasing data!
$ rm -fr ~/.var/app/org.mozilla.firefox/.mozilla/firefox/
$ cp -a ~/.mozilla/firefox/ ~/.var/app/org.mozilla.firefox/.mozilla/

$ mv ~/.mozilla/firefox ~/.mozilla/firefox.old.$(date --iso-8601=date)

$ cat /usr/local/bin/firefox 
#!/bin/sh
exec flatpak run org.mozilla.firefox "$@"

$ sudo apt update
$ sudo apt full-upgrade

flatpak update [OPTION...] [REF...] Updates applications and runtimes. [...] If no REF is given, everything is updated, as well as appstream info for all remotes.

$ flatpak update

1. Teach myself to run flatpak update additionally to apt update, manually, everytime I update my system.
2. Go crazy: let something automatically update my Flatpak apps, in my back and without my consent.

Adulthood is saying, 'But after this week things will slow down a bit' over and over until you die.

• https://www.debian.org/vote/2021/vote_003
• https://www.debian.org/vote/2022/vote_001

Work report Kubuntu: Bug bashing! I am triaging allthebugs for Plasma which can be seen here: https://bugs.launchpad.net/plasma-5.27/+bug/2053125 I am happy to report many of the remaining bugs have been fixed in the latest bug fix release 5.27.11. I prepared https://kde.org/announcements/plasma/5/5.27.11/ and Rik uploaded to archive, thank you. Unfortunately, this and several other key fixes are stuck in transition do to the time_t64 transition, which you can read about here: https://wiki.debian.org/ReleaseGoals/64bit-time . It is the biggest transition in Debian/Ubuntu history and it couldn t come at a worst time. We are aware our ISO installer is currently broken, calamares is one of those things stuck in this transition. There is a workaround in the comments of the bug report: https://bugs.launchpad.net/ubuntu/+source/calamares/+bug/2054795 Fixed an issue with plasma-welcome. Found the fix for emojis and Aaron has kindly moved this forward with the fontconfig maintainer. Thanks! I have received an https://kfocus.org/spec/spec-ir14.html laptop and it is truly a great machine and is now my daily driver. A big thank you to the Kfocus team! I can t wait to show it off at https://linuxfestnorthwest.org/. KDE Snaps: You will see the activity in this ramp back up as the KDEneon Core project is finally a go! I will participate in the project with part time status and get everyone in the Enokia team up to speed with my snap knowledge, help prepare the qt6/kf6 transition, package plasma, and most importantly I will focus on documentation for future contributors. I have created the ( now split ) qt6 with KDE patchset support and KDE frameworks 6 SDK and runtime snaps. I have made the kde-neon-6 extension and the PR is in: https://github.com/canonical/snapcraft/pull/4698 . Future work on the extension will include multiple versions track support and core24 support.

• Don t do the obvious thing; it s never what you want
  • Q. Download and run whatever code from the internet?
• Option 1: WTF, no I don t want curl bash
• Option 2: Biting the curl bash bullet
  • Privilege separation
• OMG what a mess

[source.debian-packages]
directory = "/usr/share/cargo/registry"
[source.crates-io]
replace-with = "debian-packages"

• [1] https://www.raspberrypi.com/products/raspberry-pi-400/
• [2] https://jenson.org/text/
• [3] http://tinyurl.com/27lrakl6
• [4] https://en.wikipedia.org/wiki/Watch
• [5] https://en.wikipedia.org/wiki/Calculator_watch
• [6] http://tinyurl.com/27gb7zrq
• [7] https://etbe.coker.com.au/2023/05/29/considering-convergence/
• [8] http://tinyurl.com/yuurhkvm
• [9] http://tinyurl.com/ytmw42bt
• [10] https://www.aliexpress.com/store/1103322555
• [11] https://en.wikipedia.org/wiki/Apple_Vision_Pro
• [12] https://etbe.coker.com.au/2011/10/28/desktop-augmented-reality/
• [13] https://www.aliexpress.com/item/1005005999353358.html
• [14] https://etbe.coker.com.au/2024/01/29/thinkpad-x1-yoga-gen3/
• [15] https://etbe.coker.com.au/2023/10/21/more-about-pinetime/
• [16] http://tinyurl.com/24myjjqn
• [17] https://etbe.coker.com.au/2023/10/11/pinephone-status/
• [18] https://etbe.coker.com.au/2022/03/19/more-librem5/
• [19] https://etbe.coker.com.au/2023/07/08/sandboxing-phone-apps/