The first lines of source code were added to Qt 4 in 2008. Projects with recent activity, and a code base more than five years old are likely solving vital problems and delivering consistent value, and may be organized to reward sustained effort by an engaged team of contributors.
Such a lengthy source control history in conjunction with recent activity may indicate that this code base and community are important enough to attract long-term commitment, and may also indicate a mature and relatively bug-free code base.
Note: The source code for Qt 4 might actually be older than the source control history can reveal. Many new projects begin by incorporating a large amount of source code from existing, older projects. You might be able to tell whether this is the case by looking for a rapid rise in the amount of code early in the project's history.
Qt 4 is written mostly in C++.
Across all C++ projects on Open Hub, 21% of all source code lines are comments.
This holds true for Qt 4 as well. It contains the same ratio of comment lines to code lines as the majority of C++ projects in Open Hub.
A high number of comments might indicate that the code is well-documented and organized, and could be a sign of a helpful and disciplined development team.
Over the last twelve months, Qt 4 has not seen any change in activity. This may be a good sign, and an indication that development is continuing at the same pace and not dropping off.
Open Hub makes this determination by comparing the total number of commits made by all developers during the most recent twelve months with the same figure for the prior twelve months. The number of developers and total lines of code are not considered.
The source code for Qt 4 has not been changed in over a year.
Over 75% of all projects on Open Hub have no recent activity. Open source has a "long tail" of projects whose developers have moved on. But the code is still there for all to benefit from!
For this measurement, Open Hub considers only recent changes to the code. Over the entire history of the project, 720 developers have contributed.