Product Engineering Blog

Bringing Data Sources Together with PipelineWise

TransferWise is open sourcing it’s data replication framework. PipelineWise is a Data Pipeline Framework using the Singer.io specification to replicate data from various sources to various destinations. Like many companies, the first technology stack at TransferWise was a web page with a

Product Engineering

APPLICATION AND INTERVIEW TIPS FOR ENGINEERING MANAGERS APPLYING TO TRANSFERWISE

If you’re reading this there’s a good chance you’re thinking of applying or have already applied to TransferWise - which is great news! Here’s a handy

Hiring

Kickstarting my career as a Product Engineer at TransferWise

Hi! I’m Lauri, a Product Engineer at TransferWise. After finishing my studies in Informatics at the University of Tartu, I joined TransferWise in our Tallinn office and a few

Hiring

Technical Interviews @ TransferWise

Are you about to interview for a Full Stack or Backend Engineer position at TransferWise? If yes, you’re reading the right blog. Here’s a handy guide to help

kafka

Achieving high availability with stateful Kafka Streams applications

Kafka Streams is a java library used for analyzing and processing data stored in Apache Kafka. As with any other stream processing framework, it’s capable of doing stateful and/or stateless processing on real-time data. It’s built on top of native Kafka

configuration

Don't write tests against configuration

Why writing tests against production configuration is usually not that good idea and what to do instead.

What it’s really like to be an Engineer at TransferWise in Budapest

Maybe you heard about TransferWise when a friend mentioned fast-growing fintech startups. Or maybe you’ve used us to send or receive money abroad. Either way, you might be wondering

hackathon

4 reasons why the TransferWise Hackathon rocks

Hi! I’m Saamuel, one of the 2018 TransferWise Hackathon winners. I’m now working at TransferWise as a Software Engineer in our Tallinn office while studying Information Technology at

Product Engineering

Application and interview tips for Engineers applying to TransferWise

If you’re reading this there’s a good chance you’re thinking of applying to TransferWise - which is great news! Here’s a handy guide to our application

Android

Application and interview tips for Mobile Engineers applying to TransferWise

If you’re reading this there’s a good chance you’re thinking of applying to TransferWise - which is great news! Here’s a handy guide to our application

productengineering

Application and interview tips for Site Reliability and Platform Engineers

If you’re reading this there’s a good chance you’re thinking of applying to TransferWise - which is great news! Here’s a handy guide to our application

design

Where to put application configuration?

What is a good approach to configuration? I will compare drawbacks/benefits of externalizing config vs hardcoding config in code.

bootcamp

Q&A with Smaranda, TransferWise Bootcamp Product Engineer

To give you a sneak peek into the TransferWise Summer Bootcamp, we chatted to one of our Bootcampers Smaranda who interned as a developer in our Latin America team this

microservices

What is a good size for a microservice?

To be able to answer that we should start from a different question: what kind of problems we believe smaller/independently deployable codebases solve better than a monolithic codebase with

spring boot

Building modular apps using Spring

When looking at most of the sample applications and code examples for Spring framework it may seem that everything should be defined as a bean. However, if we want to

javascript

Reducing your Webpack bundle

The last couple of months, my team at Transferwise, has been working to deliver a new feature on our product. We call this feature Money Tracker and helps TransferWise users to track their money better. I've been developing it for the web using Angular

Pull Requests that make code reviewers smile

Pull Requests (PR) are central to most software development organisations these days. Modern source control tools such as Github or Continuous Integration ones like CircleCI have helped a lot making them more accessible. Yet, it seems developers consider PRs mostly as something that you

hibernate

Hibernate and Domain Model Design

When I first learned about Hibernate about 12 years ago (I guess just about when it was at its peak) I found it to be one of the coolest libraries

A Product Manager’s guide to planning for the team

One of the best things about working at TransferWise, is how seriously we take the autonomy of our teams. Each team can (and needs to) set its own Key Performance Indicators (KPIs), come up with a mission statement, and a vision for the team.

On the Logging in Mobile Applications

Here I describe an approach from iOS point of view. An approach for Android platform is no different. I can recommend to use Timber framework as an equivalent for CocoaLumberjack. Logs? Phew! Just write something like: print("Expected `foo` to be 'bar', got:

4 fallacious reasons why we estimate

‘Estimate’ as defined in this article is: A guess about the future regarding the time or effort that a task(s) will take to be completed. In other words, anything that can be used to foresee when tasks will be done. I have to

postgresql

pg_ninja, now open source

In my previous post I wrote on how we scaled the analytics database using PostgreSQL. One of the key requirements was the possibility to replicate and obfuscate the data in real time from our main MySQL database. The tool which is managing this particular

When Groovy, assert and threads gang together to fool you

At TransferWise, we use Kafka for our messaging needs, to communicate between our micro-services and with our legacy Grails monolith. A few days ago, I faced the strangest problem with the Kafka message processing in Grails. The code that consumes Kafka messages works in

design

Illusion of Reuse

I have quite often seen situation where trying to achieve more reuse actually ends up in building the Big Ball of Mud. In some cases it is the Enterprise Domain

mysql

Scaling our analytics database

Business intelligence is at the core of any great company, and Transferwise is no exception. When I started my job as a data engineer in July 2016 my initial task was to solve a long running issue with the database used for the analytic