What do you think when you see an unknown phone number calling you at a random time? Does it fill you with dread at the thought of another robocall about a car accident you were definitely not involved in at some point over the last three years? Well you’re not alone. In the last year, robocalls and other spam has increased by over 300%. In the UK alone, it’s estimated that over 20% of unknown calls are now robo-marketing.
Truecaller is trying to take the sense of dread out of unknown numbers by using their proprietary database to identify as many unknown callers as possible. With over 100 million daily users, they process huge amounts of data, running millions of daily searches in their database.
Started originally as a blackberry (remember them) app in 2009, they quickly expanded to support Windows, Android and iPhone. They rapidly grew and in their first few years gained over 5m users performing 120m searches of their database. By 2017, they achieved over 250m worldwide users and now average about 100m daily users with over 60% of that coming from India. They’ve also created an instant messaging function as well as dabbling in p2p payments by acquiring Chillr.
In the past year they’ve moved their servers to google cloud in under 2 months, launched a brand new instant messaging product as well as ramping up their efforts to launch in emerging markets in Africa, launching a Nairobi office.
Built largely in Java, they now use Scala for the majority of their back-end programming. To get a sense of how they’ve managed to scale to such a large user base and find out a bit more about the culture that enabled their huge growth, we spoke to Sara Jako from their Stockholm office.
You’re a Swedish company based in Stockholm, but you have a huge presence in India. Why do you think it grew in this way?
I think this is because the first feature we developed and the first problem we tried to solve was knowing who was calling you.
In India the culture around communicating is a bit different, they skip the email part of the conversation and go straight to the phone call for both personal and work matters. There’s also a huge market for telesales and phone communication so it became popular because they get a lot of calls and it saves a lot of time filtering out calls they don’t want. When you use phone calls for everything, it’s hugely important to know who’s calling.
Whats the biggest growth market for you?
Still India but o looking a lot in Africa and another emerging markets. Spam calls are more of an issue in these markets so it fits with our product and the culture of the market.
So how are your teams set up?
In general we have cross-functional teams, they basically have all the capability to work independently of their own domain. We split up our devs by product, for example a messaging team that just works on that product and they have mobile engineers, backend, frontend, testers, designers, product owners - a full set up to cover every piece of that domain.
Within the larger teams cross-functional teams we have small sub teams of 2/3 people that might focus on individual elements.
We have some teams in Sweden and in India and tried to slice it up so the domains match the market. we want to minimise the amount of collaboration across timezones.
What’s the culture like in the office?
The culture is very diverse in Stockholm, we’re a 90 person team and we have 30 different nationalities, so we’re very diverse in that sense.
We try to be very open and collaborative, trying to create an environment where innovation is encouraged with regards to new tools and technologies. Open source is important to us but we have certain privacy regulations to do with the personal data we manage so there’s some compliance issues. Everything has to be signed up by our legal compliance team to make sure there are no issues with GDPR or local data protection laws.
When you look to hire devs, what makes a good fit, what sort of skills?
For backend especially we require Scala and Java and experience in certain technologies specific to the teams, we also look for people who know what’s it like working in a high load environment, we have 100m daily users so as you can imagine there’s a lot of load in the system.
Our general approach to candidates is that we’re looking for startup-ish mentality, working in similar ways to us with a similar taste for new ideas. The personality we’re looking for is innovative people who can bring new ideas, who are proactive, extroverted. Basically, develops who have ideas and can sell them to the team and onboard others .
Has a developer ever led adoption of a new technology?
Yes absolutely, there was a developer in the Android team, who suggested using Kotlin after only being with us for a few months. He sold it well and made a great case andnnow the whole company uses it in a short space of time.
What are the sort of skills that take you far at Truecaller?
I think it depends on the teams because we always need to match personalities to the teams, so there isnt one particular type of person but I think something that is consistent is that we want productive, innovative people that are product centric and want to improve the tech stack from an efficiency and a useablitity perspective.
What kind of benefits and perks do you offer
Everyone has a udemy account that can be used for any courses, we’re also a big part of the stockholm dev community so we organise meetups for Scala Stockholm, Kotlin Stockholm, so basically all teams have a joint meetup with external devs. We also try and send at least two people to google I/O and Apple’s WWDC. We try to focus on either local or mobile specific conferences.
What are the current challenges that the tech team is facing?
Each team has its own challenges, our approach is shipping fast is good, but we need quality. We really need code to work from the start because there are so many daily users, so moving fast remains a challenge.
What would you say the biggest success story from the tech side over the last year is?
So towards the end of last year we built full instant messaging capability. This is going to have the most impact in India where messaging apps are some of the biggest social networks.
We then also completed a move from our own data centres to Google cloud in about 60 days which was a huge success and I think a record for a company this size.