The first step is to install Fossil and it's quite likely that the package manager of your operating system already has it available:

sudo apt install fossil # Devuan GNU+Linux
pkg install fossil      # FreeBSD

Once your package manager ends the installation you can check its availability with the following command:

fossil version

The command above should return something like the following:

This is fossil version 2.21 [3c53b6364e] 2023-02-26 19:24:24 UTC

Fossil's documentation⁴ has the following example to export a Git repository and import it as a Fossil repository:

cd repository
git fast-export --all | fossil import --git repository.fossil

I did it differently because I wanted to adjust some things to have the imported repositories "right". As I have several repositories I created two different folders, one, git-exported, to store the exported repositories and another one, fossils, to store the new Fossil repositories:

mkdir ~/git-exported
mkdir ~/fossils

Now you can get into each Git repository folder and export it:

cd repository
git fast-export --all > ~/git-exported/repository.export

Once you have exported all your Git repositories you should go inside the ~/fossils folder and import them one by one with the command:

fossil import --git \
       --rename-master trunk \
       --attribute "your@mail.com your_username" \
       repository.fossil ~/git-exported/repository.export

The --rename-master trunk option renames your Git master branch as trunk in your new Fossil repository. Fossil, like other version control systems such as Subversion, uses trunk as the name of the master branch. If you are among the unfortunate ones who have their master branch named as "main" this option is not for you and you should check Fossil's documentation if you want to rename it.

The --attribute "your@mail.com your_username" option changes the email address "your@mail.com" from Git commits to "your_username" in the imported Fossil commits. In Fossil the default username is the same as the one you're currently using in you operating system. Obviously the given email address should exist in one or more commit messages.

If you want to change more than one email address you can do it using several --attribute options:

fossil import --git \
       --rename-master trunk \
       --attribute "your@mail.com your_username" \
       --attribute "rms@gnu.org rms" \
       --attribute "linus@kernel.org torvalds" \
       repository.fossil ~/git-exported/repository.export

The output of the import command looks like the following:

Rebuilding repository meta-data...
  100.0% complete...
Vacuuming... ok
project-id: e64b112b40eb3db188060ddb8deeaa96a6ad3b71
server-id:  bfbcd4bf8f0f64eaa2d832ddc3b4af00639624a6
admin-user: your_user (password is "XAxPVZcNQ6")

If you look closely, the output gives you the repository administrator's user and password. Keep it because you'll need it to do certain things on your repository.

Fossil has an embedded web server so you can take advantage of it to create a self-hosted server quickly and easily. The following method is enough for a system with few users, in a private network that cannot be accessed from the outside. There are different ways to set up a Fossil server and some are better than others depending on your needs, so I recommend you to check out the official documentation.

First you should create a folder to store the Fossil repositories on the server:

mkdir /path/to/your/fossils

Next copy your "fossils" to the folder on the server:

scp *.fossil user@your_server:/path/to/your/fossils/

Now you can start the server with the following command:

fossil server --port 8043 \
       --cert /path/to/your_cert.pem \
       --pkey /path/to/cert/key.pem \
       --repolist /path/to/your/fossils/

If you don't have a valid certificate you can use the follwing command:

fossil server --port 8043 \
       --cert unsafe-builtin
       --repolist /path/to/your/fossils/

Once the server is running, if you put the following url https://server_address_or_hostname:8043/ in your browser you'll access a web page with the list of your repositories. If you click on one of the repositories listed, you'll see the repository web page. In the navigation menu you should see a "login" option. Click on it and use the repository administrator's username and password. Now you can configure the repository to your liking. Check out Fossil's documentation to learn more.

If you lost your Fossil repository administrator's password, you can recover it by following these steps:

1. Go to the repositories folder in your server
2. If you don't have Sqlite installed, install it following the usual method of your operating system.

3. Open repository.fossil with Sqlite:

      sqlite3 repository.fossil
   

4. Once inside sqlite execute the following query:

      select login,pw from user;
   

   The query above will return something like:

      your_user|My3w2jRxt1
      anonymous|57EBCBD1AAE663B4
      nobody|
      developer|
      reader|
   

   The password is the value on the second column (in this example the string My3w2jRxt1).

5. Exit Sqlite with the following command

       .quit
   

Here is a very brief guide on how to start working with Fossil. This guide assumes that you know how to use Git, at a very basic level, and it's just a starting point, so I recommend you to read Fossil's documentation and the Fossil Book⁵.

I like Fossil very much and, in my opinion, it's an almost perfect mix between a centralized version control system like Subversion and a distributed one like Git. I like how easy is to put it in server mode, its web interface and, above all, the simplicity of its command line and of the most common tasks.

I think it's a great program that has a lot to offer, especially to indie programmers and small groups who are interested in self-hosting solutions. If you are looking for a simple and effective alternative to Git do not hesitate to take a look at Fossil because it may be exactly what you are looking for.