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In response to Aaron Gertler's prompt I'm writing a bit about my job. I hope this will be useful to software engineers who are in positions where their work is not EA relevant and EAs who are considering software engineering as a career path.

Edit: I just noticed that in the time since I started writing this post someone else has posted about working as a web developer. Luckily I've mostly focused my position at Wave whereas they've written about being a software engineer in general, so I think the posts are complimentary.

The basics

I work as a lead software engineer for Wave mobile money. We're working to build radically inclusive and affordable financial infrastructure in sub-Saharan Africa. My job is a mixture of programming, mentoring/leading other engineers on my team, and a bit of product design work. I work full remotely from Manchester, UK.

The job is EA-relevant in two ways:

  1. Directly - Wave is dramatically cheaper than competitors, so we save people a lot of money for people who often don't have much money in the first place. My rough estimate for the reduction in fees vs competitors is 20 million USD per month, and we're growing so this is constantly increasing!

    Less concretely there are also benefits from having a reliable, fast, and widely used mobile-money network available, see e.g. link or link.

  2. Donations - with most jobs pay is heavily location dependent, but I'm not willing to make the sacrifice of living somewhere that will leave me isolated from my friends and family in order to earn more money. Wave's pay is (almost) location-independent so as a European software engineer working for Wave allows me to donate substantially more than I would otherwise. It's roughly 3x-10x+ depending on how much the equity ends up being worth.

    Wave also matches donations up to $10,000 per year which adds another ~1x.

Of these two I think the direct work is probably the more valuable part: even taking the fee savings alone and dividing evenly over all Wave employees would be around 500K USD per Wave employee per year. But a software engineering role probably contributes more than say a callcenter role so my contribution is probably more than that. Then there's the potential for massive continued growth of Wave which could amplify the impact of work done now by 10-100x.

It's not completely clear-cut though since 1. the largest fee savings/mobile money network benefits will probably go to richer people and 2. GiveWell estimates AMF donations to be around 10x more valuable than cash transfers.


I think there's a pretty standard route to getting a software job (i.e. STEM or CS degree then junior eng role, maybe with some self-driven learning or a bootcamp first), but I'll describe my path anyway because it was slightly non-standard:

  • Maths and Physics undergraduate - I think this was very helpful in getting the right mindset for software engineering and learning hard things in general, but only a tiny fraction of what I learned during my undergraduate is actually relevant to my job.

  • PhD in computational physics - this is when I really learned to program well. I was working on large complex software so I was forced to use proper software engineering best practices to be able to deal with it. I think this was a big help in getting to where I am now. Still not sure if I would recommend doing a PhD though: it was definitely bad for my mental health.

  • 4 years as a software engineer at Biosite - more technical skills, and general software work experience. Also my introduction to the idea of prioritising work based on impact rather than just trying to do everything at once. (Really wish I'd been pushed to think about this more during my PhD!)

As well as the above I've spent a lot of time (a few hours a week for ~6 years) writing open source software for fun in my spare time and reading books on the subject. I think this probably helped to prepare me for the job as much or more than my undergraduate degree. Possibly even more than a CS undergraduate would have done.

Application process

Disclaimer: this is written from memory from 2 years ago, I might not have got everything right.

The application process took a fairly typical amount of work for a software job in my experience. It took around 10-12 hours total (including prep) over 4 parts: 2 coding exercises and 2 chats. Everyone I interacted with was friendly and pleasant throughout, I think it would have been a positive experience even if I didn't get the job.

The first chat was just a general intro to Wave and opportunity to ask questions. I didn't explicitly prep for this but I had a few questions anyway. In retrospect I probably should have spent some time thinking of more questions.

Then there were the programming exercises. These were both intense but fun, I think it was around 6 hours total + a couple of hours prep. At the time the recommended prep was something fairly wishy-washy like "think about how to solve the problem but don't write any code" (I think this has changed since). So I did this recommended prep and I also made sure I was familiar with all the technologies that I would be using by writing a quick implementation of some trivial application with same language and framework. I think I'm happy with the amount of prep that I did. I found out afterwards that I did fine on both of the exercises, but while I was doing them I felt like there wasn't enough time to fully solve the exercise (this was probably intentional). That was what made it feel intense.

Finally there was the last interview with one of the founders. I think this was a final check for culture fit, we talked about things along the lines of why I wanted to work for Wave, what motivates me in general, etc. As with the other chat I didn't really spend any time prepping for this and maybe I should have done something more.

Pretty quickly after the last interview (I think it was same or next day) I got a job offer. I took a day or so to think it through to be completely sure that it was what I wanted, but really there was no way I was going to say no!

I applied for another job at the same time as I applied for Wave. The other job was some boring corporate transportation arranging startup who rejected me (one of the reasons was because I didn't seem excited enough about their product, so I guess they got that right!). Their application process was fairly similar to the Wave one. Doing two applications at once was manageable but I don't think I could have handled more than 3 applications while also working full time.

What the job is like

What I spend my time on

This varies a lot from week-to-week, but as a rough estimate:

  • ~40% of my time writing code
  • ~25% of my time on supporting/mentoring the other software engineers on my team - helping them with any tricky problems, giving guidance on technical designs, etc.
  • ~25% of my time working on product design problems - digging into data to answer questions or look for issues; working out how to make new features easy to use, secure, and reliable.
  • ~10% of my time arranging other things - trying to make sure all of the pieces are in place for projects to go smoothly, ensuring that the right people are talking to each other, etc.

I'm the tech lead for my team, so most software engineers spend less time on mentoring/product/arranging things and more on writing code than I do. But Wave generally encourages all engineers to get involved in product decisions and take full ownership over the problems they are solving, so there might still be more non-programming work than at other companies.

More specifically: I work on the integrations team, where we build features that interact with systems run by other companies. The most common example of this kind of feature is enabling users to pay their bills in the Wave app. This might sound simple and boring but (for better or worse) many of our partners have very idiosyncratic APIs. So every new integration is an interesting challenge in figuring how we can adapt to the specific functionality and requirements of that particular API.


For Wave in particular:

  • I get to directly work on solving really important problems for people (e.g. allowing people to cheaply pay their bills from their phone instead of walking miles to an agency or paying large fees). This kind of work doesn't seem to be possible in developed world software because all of the low-hanging fruit has already been picked so you just work on making cat pictures load faster or making someone else's job slightly more efficient, etc.

  • We're growing absurdly quickly, during my time at Wave we've gone from being a tiny company that no-one had heard of to the majority of adults in Senegal being Wave users (and we've since launched in other countries too). This is incredibly exciting to watch unfold.

  • The work environment is great - my colleagues are some of the most friendly and supportive people I've met, looking after yourself is widely encouraged. They're also some of the smartest people I've ever met.

For software engineering in general:

  • It's an interesting and intellectually challenging role. There are more challenging roles, but I find that software engineering has a nice balance between "hard enough to be interesting" and "so hard you fail all the time".

  • The compensation is good, although it's usually only really really good in particular cities.


For Wave in particular:

  • Fully remote work can be isolating, this is usually counteracted by regular company trips to the countries where we operate but covid has obviously suspended that.

  • Working on technology in Africa can be... challenging, e.g. there are few/no datacenters - you either run your own machines or use hardware on another continent; the reliability of everything is relatively low - power and internet outages happen semi-regularly both for us and for our partner companies; the regulatory environment can be confusing, bureaucratic, and/or ineffective.

For software engineering in general: it definitely requires a love of and aptitude for learning about technical subjects.





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My rough estimate for the reduction in fees vs competitors is 20 million USD per month, and we're growing so this is constantly increasing!

I glanced around the website to see if this statistic was cited anywhere (or a similar statistic like "total fees saved"), and I couldn't find it.

If anyone can create a version of this number that's a bit less rough, I think it would be a fantastic addition to the careers page — it's hard to picture what most other startups could do to match that as an attraction for impact-focused candidates.

Yeah good point, I'll try to figure out something less rough.

The main source of inaccuracy is that I'm not sure what the right counterfactual is for someone doing a Wave payment. It's probably some proportion of each of: not doing the transfer at all, using some informal method, and using our main comptetitor. For simplicity in my estimate I just assumed that all transfers would have been done using our competitor.

The "all transfers use our competitor" assumption seems reasonable enough; I don't think the estimate has to be very rigorous.

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