Walking Randomly

This interview with the University of Cambridges’s Chris Richardson is part of my series of interviews on the new cohort of EPSRC Research Software Engineering Fellows.

Could you tell us a little about yourself and how you became a Research Software Engineer?

I did a PhD in GeoPhysics, followed by a PostDoc in Japan, over 15 years ago. Although it was a numerical project (on transport of magma), it was rather frustrating to code in Fortran.

I might joke now, that I could solve some of my PhD problems in 5 minutes using some of the more modern tools that we are developing! Partly, that is because of the higher level of abstraction, and the offloading of more routine tasks to libraries.

When I finished my PostDoc, I decided to apply for a Computer Officer role, which I knew would involve some dull, standard IT support but it also came with interesting stuff… code, numerics etc., without the pressure of teaching, publishing and raising grants.

I have been involved with many different computational projects over the years, including calculating neutron diffraction of adsorbed monolayers (Chemistry), and dynamic geomorphology – how a landscape changes over time as a response to tectonics (Geophysics).

More recently, I started working with the FEniCS team, first via an EPSRC dCSE grant, administered by NAG. The idea of dCSE was to improve code for running on HPC systems – we needed to get better parallel I/O into FEniCS, so it was a perfect match. It was an opportunity for me to learn C++ and really get involved in some of the internal issues in parallel coding.

After the end of the project, I continued to work on FEniCS from time to time, and I gradually got accepted as a member of the core developer team. We applied for a (now rebranded) ECSE project and also some projects with commercial partners.

What do you think is the role of a Research Software Engineer? Is it different from a ‘normal’ researcher?

I suppose it depends what you mean by “normal”. Mostly, I would expect an RSE to work collaboratively with other scientists and engineers, and not to lead scientific projects themselves. So, whilst not being a PI on a project, they need to communicate effectively with the scientific team they are working with, provide the technical expertise to realise the computational aspects of the project, and have some scientific understanding too.

Ultimately, it is important to have something invested in a collaboration, so it is not just a service, but a personal involvement, which might result in a joint publication or another form of recognition. And that is not so different from many “normal” researchers below the PI level.

You’ve recently won an EPSRC RSE Fellowship – congratulations! Can you give a brief overview of your project?

I am part of a team, writing a finite element analysis library. Finite element analysis (FEA) goes way back to the early days of computing, and has been used by engineers for decades, because it is very good at modelling physics in arbitrary shaped objects. One of the problems of FEA is that it is tricky to program, so our library FEniCS takes care of some of the more difficult aspects, whilst allowing the user a great deal of flexibility in describing the equations or meshes to solve on.

I am extending FEniCS to use: (a) complex numbers – useful for wave-like phenomena, (b) powerful non-linear solvers, which can solve difficult problems more quickly, (c) curved boundaries – needed for interface problems, e.g. surface tension, and (d) dynamic meshes, which can change in geometry and topology over time.

As well as “just doing programming”, I want to engage with the scientific community to apply these techniques to actual physical problems, and form collaborations with domain scientists in their specialist areas. Ultimately, I want to build up a small RSE team who can help scientists across diverse fields to solve their computational problems, using FEniCS, or other relevant packages.

I also hope to be involved in teaching and training more sustainable practices in the scientific community, helping people to use revision control, and write more reusable code.

How long did it take you to write your Fellowship application?

The EPSRC call was very widely advertised, and I received multiple emails about it. Since the first hurdle was small – only an A4 sheet – I decided to give it a go.

I guess it was a standard EPSRC call template, and things like – ‘Early career stage researcher’ seemed like a possible blocker, but the A4 sheet was accepted, so I made a full application, and the feedback from reviewers was very positive. Writing the full application was very stressful, and really a full-time occupation for a few weeks. I felt like someone who had an exam but hadn’t revised for it. Some friends said to me: “make it easy for the reviewers” – which is good advice. By closely reading the call documents, I tried to tick off as many points as possible, and make my application match the criteria as well as I could.

I was quite nervous for the interview, and I’m sure I said a few stupid things, but I don’t think that’s particularly unusual. Everyone at EPSRC was very friendly.

Who are your project partners?

I’ve got academic project partners at Southampton and Oxford Universities in the UK, as well as at Simula Research in Norway, and Rice University in the US. Industrial partners are BP and Melior Innovations.

Who are the users of FEniCS?

FEniCS has got a lot of users across the world, but in many ways, it is difficult to know who they are. We have many different distribution channels, so we can’t really monitor downloads. One estimate is the number of questions we get on the user forum. These have come from 50+ countries around the world, and average about two questions per day.

How long have you been involved?

I have been involved for about the last 5 years, gradually building up from being a user, to a part-time contributor, to core developer.

Do you find it it difficult to get recognition/ full time employment for your work?

I’m not sure if I get recognition, I suppose becoming an EPSRC fellow is recognition, and I usually do get included as an author on scientific papers. Recently we started issuing release FEniCS notes in Arch. Num. Soft., which is a way to get recognition for pure library development.

How many Fenics developers and which version control system do you use?

There are about half a dozen core contributors, mostly Europe-based, and we use “git” on bitbucket.org.

Tell me about your group.

I am in a small institute, with researchers from Earth Sciences, Chemistry, Chemical Engineering, Engineering and Applied Maths. I am the only RSE in the building, but we are on the West Cambridge campus, which includes the University High Performance Computing Service (HPCS), just across the road. I am working with Filippo Spiga from HPCS and his team. I also spend quite a lot of time at the Engineering Department, where one of the other FEniCS developers (Dr Garth Wells) is based.

What’s your plan for the future?

The head of the BP Institute is a professor in Earth Sciences, and he has always been very supportive. He sees my RSE fellowship as an opportunity to expand our RSE activities in the future. I want to help researchers write RSE time into their grant proposals, so we can collaborate on a wide range of projects, continuing after the period of the fellowship.

Which programming languages and technologies do you regularly use?

For serious coding, almost everything is in C++11 now. Some people complain that it is not good for scientific computing, but there are some excellent libraries, such as Eigen3 and boost::multi_array which provide highly optimised matrix algebra, and access to multi-dimensional arrays, in much the same way as Fortran or C.

• Python is very useful for doing things quickly, and has really taken over almost entirely from shell scripting.
• SWIG – a bit esoteric, but essential for wrapping C++ to Python.
• Google tests. Atlassian Bamboo CI. Run tests inside docker inside Bamboo.
• ParaView – really useful for visualisation.

What would we like? We have a user forum, based on q2a, but it would be much nicer if it had a “Stack Exchange” like interface. Maybe we should investigate using Area51.

Are there any languages/technologies that you used to use a lot but have now moved away from? Why?

• Fortran. I know it’s still widely used, and there are modern versions, but I’m not going back.
• Shell scripting. I mostly use Python instead now – it’s easier to understand.

Is there anything on your ‘to-learn’ list?

• How to use Python in ParaView
• How to write threaded code that is efficient for Finite Element
• Using hybrid OpenMP/MPI
• Intel Xeon Phi

Do you have any advice for anyone who wants to become a Research Software Engineer?

I think you need to be multi-skilled. You need to understand people – psychology and culture; programming – obviously; and have some basic understanding of the science itself, even if you don’t know all the details.