Technology
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We built network isolation for 1,500 services to make Monzo more secure
We've been working on isolating the 1,500 services that power Monzo. The sheer size and complexity of our platform made this difficult. But by protecting us against compromised services, it makes Monzo more secure.
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How our security team handle secrets
We recently designed a new system to manage secret information safely – from the keys that we use to sign your Mastercard transactions, to credentials for external services.
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How we experiment at Monzo
Making big decisions is hard. So at Monzo, we test our ideas out whenever we can. Here's how that works!
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Laying the foundation for a data team
At Monzo, we want to build the best bank account in the world. Today, more than ever before, data is central to creating wonderful customer experiences and efficient internal operations.
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How we respond to incidents
A good response process can mean the difference between something being resolved in minutes and an issue developing into something worse!
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The role of technology in social inclusion
The technology we use to create Monzo can play a key part in our mission to make money work for everyone.
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How we accidentally broke our Android notification sounds (and fixed them!)
We encountered an interesting bug in our Android app notifications. Here's how we fixed it.
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4 useful services your bank should not be charging you for
Click to read more
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We’re experiencing problems with some bank transfers
Some bank transfers aren't working. We're working on sorting it out asap.
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We deployed Envoy Proxy to make Monzo faster
We moved our remote procedure call (RPC) service mesh from Linkerd to Envoy to make Monzo faster.
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How we improved our staff VPN
OpenVPN is great, but there were some things we wanted to change.
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How we built Monzo Chat on Android
We’ve built bespoke software from scratch, that helps us manage chats in the app. Here's how we implemented it on Android.
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How we prepared our systems for our £20 million crowdfunding round
We prepared our systems for crowdfunding by shedding load, and built tools to help us monitor on the day.
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How we load tested our bank before our £20 million crowdfunding round
More than 9,000 people opened their apps to invest in the first five minutes of crowdfunding. To make sure we were ready, we ran tests to simulate the extra load and upgraded our platform to cope with it.
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How we built a backend for our £20 million crowdfunding round
We architected and built a scalable backend to support 36,000 investments.