Joe Wells

I am a Senior Research Fellow (permanent position) in the ULTRA (Logic, Types, and Rewriting) group in the Computer Science Department in the School of Mathematical and Computer Sciences at Heriot-Watt University (more info) in Edinburgh (more info), Scotland (more info).

(The members of the Computer Science department formerly belonged to the now defunct Computing and Electrical Engineering Department. The domain is now obsolete; please don't use it anymore.)


Current Courses:
Previously Taught Courses/Modules:
  • Foundations 2 (course F29FB), semester 2 in academic years 2021/-22 and 2020/-21 (both years with Fairouz Kamareddine), 2018/-19, 2017/-18, 2016/-17, 2015/-16, 2014/-15 (this year with Manuel Maarek), 2012/-13, 2011/-12, 2010/-11, 2009/-10, and 2008/-09.
  • Programming Languages (GA) (course F28LL), September (first) semester (the other half of this course was in the last semester taught by Idris Ibrahim) in academic years 2022/-23, 2021/-22, and 2020/-21.
  • Formal Specification (course F29FS), academic year 2011/-12 semester 2.
  • Foundations 1 (course F29FA), academic year 2009/-10 semester 1 and academic year 2008/-09 semester 2.
  • Foundations of Computing (module F2.2AW1), term 1 in academic years 2006/-07, 2005/-06, 2004/-05, and 2003/-04.

Student Projects

Some of the student projects that I have supervised have made their results public and they are listed here. All of the software produced by these projects is free/libre software, sometimes called "open source" software.


My research interests are in the applications of advanced type systems and rewriting techniques primarily motivated by issues in the design and implementation of convenient, efficient, scalable, secure, and reliable programming language systems.

Research Effort Participation

I have been involved in the following research efforts.

Research Resources

I have made available the following resources related to my research.

Research Software

I have been involved in the development of research software, including the following.

Research Events

I have been involved (other than as an ordinary participant) in the following international scientific meetings.

Research Reviewing

In general, I am happy to review conference and journal submissions in my area of expertise. However, I will not use web interfaces for my reviews unless I am myself on the PC of the conference to which a paper is submitted. I am willing to consider conference subreviewing requests and journal reviewing requests under the following circumstances:

I will not use a web interface, for a vast number of reasons. Just some of the reasons include the following. I am not willing to spend time working around the bugs of a web interface. I am not willing to manage another web account and its password.

Debugging Computer and Network Problems

Problems with computer hardware and software and networking can be difficult to diagnose and fix. If you want my help with any problems you are having, please be sure to include this information in your problem report:

Contact Information

E-mail: Local Part: Joe.Wells
Voice (Office Tel.): +44 131 451 3869
(I often work at home, so if I do not answer my office telephone, colleagues (not including students taking courses I am teaching) may try calling me at home. Send e-mail to get my home (land-line) or mobile telephone number.)
(Dept. Tel.): +44 131 451 3328
UK Local Time: 2024-07-21 T 05:38:03+01:00 (Sunday)
(You may need to reload this page for the above time to be accurate.)
UK Local Time Zone  (Current): +01:00 (Offset relative to UTC. This time zone is locally called BST.)
(Winter): +00:00 (Offset relative to UTC. This time zone is locally called BDT.)
(In the UK a summer/winter time-zone change occurs on the last Sunday in March/October at 01:00+00:00.)
Fax (Dept. Office): +44 131 451 3732
(Please notify me by e-mail if you send a fax to the above number so I can know to pick up the fax.)
Post: School of Mathematical and Computer Sciences
Heriot-Watt University
Riccarton (more info)
EH14 4AS
Office: EM 161 (Room 1.61, Earl Mountbatten Building)
(As of 2007-08-15, this is building number 3 on this map and between numbers 1 and 3 on this map. Both maps are linked from this web page with directions. It is also building number 2 on this obsolete older map.)


Some Minor Web Pages of Mine

Features of the Heriot-Watt Riccarton Campus

Most of the Heriot-Watt Riccarton Campus is quite picturesque. There are many exotic trees, and a wide range of wildlife. One of our staff members, Adrian Hurt, has taken a number of pictures of the wildlife on the campus. I like his pictures of a goose, a number of young cygnets, and a family of swans.

One kind of wildlife is particularly common. The Riccarton campus is overrun by rabbits. In the winter, the Riccarton rabbits seem to have an unusual mode of hibernation. Periodically, the swarms of rabbits seem to suddenly disappear. There is some speculation that at these times the rabbits are beset by armed opponents. Photographic evidence obtained by Adrian shows that the rabbits may be preparing their response.

Adrian has also obtained photographs indicating that our school's new Colin Maclaurin building may be concealing some hidden purpose. It is possible that this has something to do with strange transformations that the Riccarton rabbits have undergone near the Colin Maclaurin building. There are also unholy buses in the vicinity, although it is unclear if this is related.

Recommended Reading and Viewing

Serious Stuff

  • The best source in the world of news on free and open source software and Linux is LWN. It is so good that I even pay for a subscription just to be able to read its main weekly report when it comes out instead of waiting a week to read it as a non-subscriber. My subscription to LWN is the only paid subscription I have had for the last 20 years (whether delivered by Internet or by physical post). Really, it's that good. Go read it, and subscribe if you like it.
  • One of the most interesting works of Mark Twain (Samuel Clemens) is Letters from the Earth. Permission to publish this work was withheld by his daughter until more than half a century after his death, for good reason, because Mark Twain is certainly observant and logical and we all know what trouble observation and logic can cause.
  • In 1929, John Desmond Bernal wrote a brilliant prophetic essay about the long-term future of humanity: our living environment, our physical nature, and our psychological nature. The breadth of this essay can only be hinted at by the following quotes:

    We shall have very sane reactionaries at all periods warning us to remain in the natural and primitive state of humanity, which is usually the last stage but one in their cultural history. But the secondary consequences of what men have already done — the reactionaries as much as any — will carry them away then as now.

    …; the dangers to the whole structure of humanity and its successors will not decrease as their wisdom increases, because, knowing more and wanting more they will dare more, and in daring will risk their own destruction. But this daring, this experimentation, is really the essential quality of life.

  • Isaac Asimov's excellent article on The Relativity of Wrong explains how scientific theories improve over previous ones without necessarily ever being “right”.
  • Darius Rejali gives a brief overview of the history of modern methods of torture, i.e., those which cause maximum agony and suffering while leaving no visible marks. These methods include forced standing, low-amperage high-voltage electric shock, and waterboarding. Many such torture methods have been developed entirely inside democracies like the USA, the UK, and France and only later exported by agents of those democracies to totalitarian governments.
  • A recent Gallup World Poll (conducted by The Gallup Organization) included surveys of 90% of the Muslim population worldwide about beliefs related to ongoing conflict between Muslims and the USA and the UK. The results indicate that religion is actually a minor factor in the conflict and that instead the “root cause” of conflict is concerns about “occupation and U.S. domination” and “perceptions of being under siege” by the USA. (Of course, religion does influence the perceptions of who is “us” and who is “them”.)
  • Steven Pinker explains that statistics on violence (war, murder, torture, cruelty, etc.) indicate how from millennium to millennium, century to century, decade to decade, and year to year, things are getting better. If we think things are bad now, this is mostly because (1) worldwide social standards for acceptable behavior are rising faster than behavior is improving, and (2) we are often unaware of enough history to see things in perspective.
  • John Taylor Gatto is a retired school teacher who was named New York City Teacher of the Year in 1989, 1990, and 1991, and New York State Teacher of the Year in 1991. His short essay The 7-Lesson Schoolteacher explains how compulsory government schooling has little to do with education, and how it often damages students more than it helps. When you have more time, I recommend reading his book The Underground History of American Education, a detailed historical analysis of how the “education” system developed. You can read also read a review and discussion of this book.
  • Alan Sokal's marvelously fun hoax article Transgressing the Boundaries: Towards a Transformative Hermeneutics of Quantum Gravity published in 1996 in the “journal” Social Text begins with the following wry (and technically completely accurate) commentary about the relationship between science and culture:

    There are many natural scientists, and especially physicists, who continue to reject the notion that the disciplines concerned with social and cultural criticism can have anything to contribute, except perhaps peripherally, to their research. Still less are they receptive to the idea that the very foundations of their worldview must be revised or rebuilt in the light of such criticism. Rather, they cling to the dogma imposed by the long post-Enlightenment hegemony over the Western intellectual outlook, which can be summarized briefly as follows: that there exists an external world, whose properties are independent of any individual human being and indeed of humanity as a whole; that these properties are encoded in “eternal” physical laws; and that human beings can obtain reliable, albeit imperfect and tentative, knowledge of these laws by hewing to the “objective” procedures and epistemological strictures prescribed by the (so-called) scientific method.

    For publishing this paper, the editors of Social Text won the 1996 Ig Nobel Prize for Literature (and winning the Ig Nobel is usually not an honor). The award presentation honored the editors “for eagerly publishing research that they could not understand, that the author said was meaningless, and which claimed that reality did not exist”. The publication of this paper triggered an enormous and wide-ranging debate (with hundreds (probably thousands) of articles) about the deleterious effects of postmodernism (and other movements influenced by postmodernism).

  • Douglas Hofstadter has written an excellent article on why we don't need race-neutral ways of referring to people and their roles. (Satire warning!)
  • Patrick Forterre gives a possible explanation of how the three domains of life (Bacteria, Archaea, and Eukarya) could have been formed from RNA-only cell ancestors by three distinct infection events where DNA viruses merged with their targets instead of killing them. (It is not entirely clear whether Bacteria and Archaea should be considered distinct domains, but Forterre's theory could also help explain two domains.) Forterre's proposal can explain the homologies between the RNA machineries of the three domains, the distinct differences in the domains' DNA machineries, the distinct lipid chirality of the Archaea, etc. This supports the hypothesis that the last common ancestor of cellular life forms on Earth was an RNA-only cell, and extends it with the hypothesis that there was a separate viral last common ancestor for the DNA portion of life.
  • The report of this 1968 NATO conference appears to be where the phrases “software engineering” and “software crisis” were invented.
  • Richard Dawkins analyzes how human minds are vulnerable to being infected by false beliefs.
  • This analysis by Maia Szalavitz illustrates how the media abuses statistics in coverage of touchy subjects.

Lighter Stuff

Alter Egos

“Joe Wells” is also:

Some Thoughts

I did not write this, but it seemed worth sharing:

I believe in time,
matter, and energy,
which make up the whole of the world.

I believe in reason, evidence and the human mind,
the only tools we have;
they are the product of natural forces
in a majestic but impersonal universe,
grander and richer than we can imagine,
a source of endless opportunities for discovery.

I believe in the power of doubt;
I do not seek out reassurances,
but embrace the question,
and strive to challenge my own beliefs.

I accept human mortality.

We have but one life,
brief and full of struggle,
leavened with love and community,
learning and exploration,
beauty and the creation of
new life, new art, and new ideas.

I rejoice in this life that I have,
and in the grandeur of a world that preceded me,
and an earth that will abide without me.

Web Page Validation

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