Fossil

might be biased in favor of Fossil.  Ask around for second opinions from
people who have used <em>both</em> Fossil and Git.

&#185;<small><i>Git does not support
wiki, tickets, or tech-notes, so those elements will not transfer when
exporting from Fossil to Git.</i></small>

<h2>2.0 Executive Summary:</h2>




<blockquote><table border=1 cellpadding=5 align=center>
<tr><th width="50%">GIT</th><th width="50%">FOSSIL</th></tr>
<tr><td>File versioning only</td>
    <td>Versioning, Tickets, Wiki, and Technotes</td></tr>
<tr><td>Ad-hoc, pile-of-files key/value database</td>
    <td>Relational SQL database</td></tr>
................................................................................
<tr><td>One check-out per repository</td>
    <td>Many check-outs per repository</td></tr>
<tr><td>Remembers what you should have done</td>
    <td>Remembers what you actually did</td></tr>
<tr><td>GPL</td><td>BSD</td></tr>
</table></blockquote>

<h2>3.0 Discussion</h2>

<h3>3.1 Feature Set</h3>

Git provides file versioning services only, whereas Fossil adds
integrated [./wikitheory.wiki | wiki],
[./bugtheory.wiki | ticketing &amp; bug tracking],
[./embeddeddoc.wiki | embedded documentation], and
[./event.wiki | Technical notes].
These additional capabilities are available for Git as 3rd-party and/or
................................................................................
the stand-alone Fossil executable together with a 2-line CGI script
suffice to instantiate a full-featured developer website.  To accomplish
the same using Git requires locating, installing, configuring, integrating,
and managing a wide assortment of separate tools.  Standing up a developer
website using Fossil can be done in minutes, whereas doing the same using
Git requires hours or days.

<h3>3.2 Database</h3>

The baseline data structures for Fossil and Git are the same (modulo
formatting details).  Both systems store check-ins as immutable
objects referencing their immediate ancestors and named by a
cryptographic hash of the check-in content.

The difference is that Git stores its objects as individual files
................................................................................
The ease with which check-ins can be located and queried in Fossil
has resulted in a huge variety of reports and status screens
([./webpage-ex.md|examples]) that show project state
in ways that help developers
maintain enhanced awareness and comprehension
and avoid errors.

<h3>3.3 Cathedral vs. Bazaar</h3>

Fossil and Git promote different development styles.  Git promotes a
"bazaar" development style in which numerous anonymous developers make
small and sometimes haphazard contributions.  Fossil
promotes a "cathedral" development model in which the project is
closely supervised by an highly engaged architect and implemented by
a clique of developers.
................................................................................
Work in progress from one developer is readily visible to all other
developers and to the project leader, well before the code is ready
to integrate.  Fossil places a lot of emphasis on reporting the state
of the project, and the changes underway by all developers, so that
all developers and especially the project leader can maintain a better
mental picture of what is happening, and better situational awareness.

<h3>3.4 Linux vs. SQLite</h3>

Git was specifically designed to support the development of Linux.
Fossil was specifically designed to support the development of SQLite.

Both SQLite and Linux are important pieces of software.
SQLite is found on far more systems than Linux.  (Almost every Linux
system uses SQLite, but there are many non-Linux systems such as
................................................................................
Git is designed for this scenario.

SQLite uses cathedral-style development.  95% of the code in SQLite
comes from just three programmers, 64% from just the lead developer.
And all SQLite developers know each other well and interact daily.
Fossil is designed for this development model.

<h3>3.5 Lots of little tools vs. Self-contained system</h3>

Git consists of many small tools, each doing one small part of the job,
which can be recombined (by experts) to perform powerful operations.
Git has a lot of complexity and many dependencies and requires an "installer"
script or program to get it running.

Fossil is a single self-contained stand-alone executable with hardly
................................................................................

The designer of Git says that the unix philosophy is to have lots of
small tools that collaborate to get the job done.  The designer of
Fossil says that the unix philosophy is "it just works".  Both
individuals have written their DVCSes to reflect their own view
of the "unix philosophy".

<h3>3.6 One vs. Many Check-outs per Repository</h3>

A "repository" in Git is a pile-of-files in the ".git" subdirectory
of a single check-out.  The check-out and the repository are inseperable.

With Fossil, a "repository" is a single SQLite database file
that can be stored anywhere.  There
can be multiple active check-outs from the same repository, perhaps
open on different branches or on different snapshots of the same branch.
Long-running tests or builds can be running in one check-out while
changes are being committed in another.

<h3>3.7 What you should have done vs. What you actually did</h3>

Git puts a lot of emphasis on maintaining
a "clean" check-in history.  Extraneous and experimental branches by
individual developers often never make it into the main repository.  And
branches are often rebased before being pushed, to make
it appear as if development had been linear.  Git strives to record what
the development of a project should have looked like had there been no
................................................................................
is that this makes the history "accurate".  In actual practice, the
superior reporting tools available in Fossil mean that the added "mess"
is not a factor.

One commentator has mused that Git records history according to
the victors, whereas Fossil records history as it actually happened.

<h3>3.8 GPL vs. BSD</h3>

Git is covered by the GPL license whereas Fossil is covered by
a two-clause BSD license.

Consider the difference between GPL and BSD licenses:  GPL is designed
to make writing easier at the expense of making reading harder.  BSD is
designed to make reading easier at the expense of making writing harder.
................................................................................
implementations themselves, not to the projects which the systems store.
Nevertheless, one can see a more GPL-oriented world-view in Git and a
more BSD-oriented world-view in Fossil.  Git encourages anonymous contributions
and siloed development, which are hallmarks of the GPL/bazaar approach to
software, whereas Fossil encourages a more tightly collaborative,
cliquish, cathedral-style approach more typical of BSD-licensed projects.

<h2>4.0 Missing Features</h2>

Most of the capabilities found in Git are also available in Fossil and
the other way around. For example, both systems have local check-outs,
remote repositories, push/pull/sync, bisect capabilities, and a "stash".
Both systems store project history as a directed acyclic graph (DAG)
of immutable check-in objects.

But there are a few capabilities in one system that are missing from the
other.

<h3>4.1 Features found in Fossil but missing from Git</h3>

  *  <b>The ability to show descendents of a check-in.</b>

   Both Git and Fossil can easily find the ancestors of a check-in.  But
   only Fossil shows the descendents.  (It is possible to find the
   descendents of a check-in in Git using the log, but that is sufficiently
   difficult that nobody ever actually does it.)
................................................................................
  *  <b>The [/help?cmd=ui|fossil ui] command</b>

   Fossil supports an integrated web interface.  Some of the same features
   are available using third-party add-ons for Git, but they do not provide
   nearly as many features and they are not nearly as convenient to use.


<h3>4.2 Features found in Git but missing from Fossil</h3>

  *  <b>Rebase</b>

   Because of its emphasis on recording history exactly as it happened,
   rather than as we would have liked it to happen, Fossil deliberately
   does not provide a "rebase" command.  One can rebase manually in Fossil,
   with sufficient perserverence, but it is not something that can be done with

might be biased in favor of Fossil.  Ask around for second opinions from
people who have used <em>both</em> Fossil and Git.

&#185;<small><i>Git does not support
wiki, tickets, or tech-notes, so those elements will not transfer when
exporting from Fossil to Git.</i></small>

<h2>2.0 Differences Between Fossil And Git</h2>

Differences between Fossil and Git are summarized by the following table,
with further description in the text that follows.

<blockquote><table border=1 cellpadding=5 align=center>
<tr><th width="50%">GIT</th><th width="50%">FOSSIL</th></tr>
<tr><td>File versioning only</td>
    <td>Versioning, Tickets, Wiki, and Technotes</td></tr>
<tr><td>Ad-hoc, pile-of-files key/value database</td>
    <td>Relational SQL database</td></tr>
................................................................................
<tr><td>One check-out per repository</td>
    <td>Many check-outs per repository</td></tr>
<tr><td>Remembers what you should have done</td>
    <td>Remembers what you actually did</td></tr>
<tr><td>GPL</td><td>BSD</td></tr>
</table></blockquote>



<h3>2.1 Feature Set</h3>

Git provides file versioning services only, whereas Fossil adds
integrated [./wikitheory.wiki | wiki],
[./bugtheory.wiki | ticketing &amp; bug tracking],
[./embeddeddoc.wiki | embedded documentation], and
[./event.wiki | Technical notes].
These additional capabilities are available for Git as 3rd-party and/or
................................................................................
the stand-alone Fossil executable together with a 2-line CGI script
suffice to instantiate a full-featured developer website.  To accomplish
the same using Git requires locating, installing, configuring, integrating,
and managing a wide assortment of separate tools.  Standing up a developer
website using Fossil can be done in minutes, whereas doing the same using
Git requires hours or days.

<h3>2.2 Database</h3>

The baseline data structures for Fossil and Git are the same (modulo
formatting details).  Both systems store check-ins as immutable
objects referencing their immediate ancestors and named by a
cryptographic hash of the check-in content.

The difference is that Git stores its objects as individual files
................................................................................
The ease with which check-ins can be located and queried in Fossil
has resulted in a huge variety of reports and status screens
([./webpage-ex.md|examples]) that show project state
in ways that help developers
maintain enhanced awareness and comprehension
and avoid errors.

<h3>2.3 Cathedral vs. Bazaar</h3>

Fossil and Git promote different development styles.  Git promotes a
"bazaar" development style in which numerous anonymous developers make
small and sometimes haphazard contributions.  Fossil
promotes a "cathedral" development model in which the project is
closely supervised by an highly engaged architect and implemented by
a clique of developers.
................................................................................
Work in progress from one developer is readily visible to all other
developers and to the project leader, well before the code is ready
to integrate.  Fossil places a lot of emphasis on reporting the state
of the project, and the changes underway by all developers, so that
all developers and especially the project leader can maintain a better
mental picture of what is happening, and better situational awareness.

<h3>2.4 Linux vs. SQLite</h3>

Git was specifically designed to support the development of Linux.
Fossil was specifically designed to support the development of SQLite.

Both SQLite and Linux are important pieces of software.
SQLite is found on far more systems than Linux.  (Almost every Linux
system uses SQLite, but there are many non-Linux systems such as
................................................................................
Git is designed for this scenario.

SQLite uses cathedral-style development.  95% of the code in SQLite
comes from just three programmers, 64% from just the lead developer.
And all SQLite developers know each other well and interact daily.
Fossil is designed for this development model.

<h3>2.5 Lots of little tools vs. Self-contained system</h3>

Git consists of many small tools, each doing one small part of the job,
which can be recombined (by experts) to perform powerful operations.
Git has a lot of complexity and many dependencies and requires an "installer"
script or program to get it running.

Fossil is a single self-contained stand-alone executable with hardly
................................................................................

The designer of Git says that the unix philosophy is to have lots of
small tools that collaborate to get the job done.  The designer of
Fossil says that the unix philosophy is "it just works".  Both
individuals have written their DVCSes to reflect their own view
of the "unix philosophy".

<h3>2.6 One vs. Many Check-outs per Repository</h3>

A "repository" in Git is a pile-of-files in the ".git" subdirectory
of a single check-out.  The check-out and the repository are inseperable.

With Fossil, a "repository" is a single SQLite database file
that can be stored anywhere.  There
can be multiple active check-outs from the same repository, perhaps
open on different branches or on different snapshots of the same branch.
Long-running tests or builds can be running in one check-out while
changes are being committed in another.

<h3>2.7 What you should have done vs. What you actually did</h3>

Git puts a lot of emphasis on maintaining
a "clean" check-in history.  Extraneous and experimental branches by
individual developers often never make it into the main repository.  And
branches are often rebased before being pushed, to make
it appear as if development had been linear.  Git strives to record what
the development of a project should have looked like had there been no
................................................................................
is that this makes the history "accurate".  In actual practice, the
superior reporting tools available in Fossil mean that the added "mess"
is not a factor.

One commentator has mused that Git records history according to
the victors, whereas Fossil records history as it actually happened.

<h3>2.8 GPL vs. BSD</h3>

Git is covered by the GPL license whereas Fossil is covered by
a two-clause BSD license.

Consider the difference between GPL and BSD licenses:  GPL is designed
to make writing easier at the expense of making reading harder.  BSD is
designed to make reading easier at the expense of making writing harder.
................................................................................
implementations themselves, not to the projects which the systems store.
Nevertheless, one can see a more GPL-oriented world-view in Git and a
more BSD-oriented world-view in Fossil.  Git encourages anonymous contributions
and siloed development, which are hallmarks of the GPL/bazaar approach to
software, whereas Fossil encourages a more tightly collaborative,
cliquish, cathedral-style approach more typical of BSD-licensed projects.

<h2>3.0 Missing Features</h2>

Most of the capabilities found in Git are also available in Fossil and
the other way around. For example, both systems have local check-outs,
remote repositories, push/pull/sync, bisect capabilities, and a "stash".
Both systems store project history as a directed acyclic graph (DAG)
of immutable check-in objects.

But there are a few capabilities in one system that are missing from the
other.

<h3>3.1 Features found in Fossil but missing from Git</h3>

  *  <b>The ability to show descendents of a check-in.</b>

   Both Git and Fossil can easily find the ancestors of a check-in.  But
   only Fossil shows the descendents.  (It is possible to find the
   descendents of a check-in in Git using the log, but that is sufficiently
   difficult that nobody ever actually does it.)
................................................................................
  *  <b>The [/help?cmd=ui|fossil ui] command</b>

   Fossil supports an integrated web interface.  Some of the same features
   are available using third-party add-ons for Git, but they do not provide
   nearly as many features and they are not nearly as convenient to use.


<h3>3.2 Features found in Git but missing from Fossil</h3>

  *  <b>Rebase</b>

   Because of its emphasis on recording history exactly as it happened,
   rather than as we would have liked it to happen, Fossil deliberately
   does not provide a "rebase" command.  One can rebase manually in Fossil,
   with sufficient perserverence, but it is not something that can be done with