Why Scientific Software Wants To Be Free

Not sure if I missed this earlier, but it strikes me as a hugely important issue that deserves a wider audience whether or not it is brand new:

Astronomical software is now a fact of daily life for all hands-on members of our community. Purpose-built software for data reduction and modeling tasks becomes ever more critical as we handle larger amounts of data and simulations. However, the writing of astronomical software is unglamorous, the rewards are not always clear, and there are structural disincentives to releasing software publicly and to embedding it in the scientific literature, which can lead to significant duplication of effort and an incomplete scientific record.

We identify some of these structural disincentives and suggest a variety of approaches to address them, with the goals of raising the quality of astronomical software, improving the lot of scientist-authors, and providing benefits to the entire community, analogous to the benefits provided by open access to large survey and simulation datasets. Our aim is to open a conversation on how to move forward.

We advocate that: (1) the astronomical community consider software as an integral and fundable part of facility construction and science programs; (2) that software release be considered as integral to the open and reproducible scientific process as are publication and data release; (3) that we adopt technologies and repositories for releasing and collaboration on software that have worked for open-source software; (4) that we seek structural incentives to make the release of software and related publications easier for scientist-authors; (5) that we consider new ways of funding the development of grass-roots software; (6) and that we rethink our values to acknowledge that astronomical software development is not just a technical endeavor, but a fundamental part of our scientific practice.

Leaving aside the obvious and welcome element of calling for an open source approach (and, presumably, open source release if possible), there is deeper issue here: the fact that astronomy - and by extension, all science - is increasingly bound up with software, and that software is no longer an incidental factor in its practice.

A consequence of this is that as software moves ever-closer to the heart of the scientific process, so the need to release that code under free software licences increases. First, so that others can examine it for flaws and/or reproduce the results it produces. And secondly, so that other scientists can build on that code, just as they build on its results. In other words, it is becoming evident that open source is indispensable for *all* science, and not just the kind that proudly preclaims itself open.