Abusing Android build system

A way to manage multiple Android flavours and releases storing the secrets securely in Git

Secrets in Git

HOWTO store secrets easily in git using git-crypt. Our way to keep Android signing keys.

Power curves in Redash with Clickhouse

There is a lot written on the internet regarding power curves. They are a very powerful tool to better understand how users of a service are behaving. Do you have a strong small user base? Are they more evenly distributed? With traditional Monthly Active User (MAU) you don’t get to know it. Power curves are easy to calculate. While I was working at FWD we implemented them in Clickhouse and displayed them with Redash.

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Unifying health checks in services

Microservices became very trendy. Nowadays every company says it is using them. They can scale your organization, make your life better and solve world hunger. No matter if it is true or not, and if the services are micro or not, usually no one talks about how to know if they are healthy or not. Both Kubernetes and Mesos/Marathon provide health and/or readiness checks to know if a task is doing ok and ready to serve traffic.

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Cohorts in Redash with Clickhouse

Cohorts are a common way to display and track the retention of a service (buyers, active users, whatever_you_need). As I said before in my team we heavily use Redash, and we use it together with Clickhouse. To get the cohorts calculated, you need some SQL tricks. I couldn’t find much on the Internet on how to do it, so here is our contribution. Clickhouse is really powerful but it has its own special flavor of SQL.

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Checklist for an engineering interview process

Usually the job interviews are seen as a process where a company is choosing a person to hire. Candidates sometimes don’t take the chance also to interview the company and try to gather as much information as possible to see if it would be a nice place to work. I have my own list of things I would like to know from a company. Some to ask during the process, others you can find them by doing some small research.

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Canvas, browser and the sun

Lately I have been learning on how to use the HTML Canvas to generate nice images. It is a work in progress. For that I have followed part of the Creative Coding course (really nice one if you want to get started). And the same guy has created the nice canvas-sketch tool to get the basics of the workflow going. As one of my first tries in this world of creative coding has been playing with the sun trajectories in the sky.

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Managing Redash from Code

In my company we use Redash quite a lot to display vast amount of information. If you don’t know Redash, maybe you should check it out, it is an open source tool that connects to many different DBs and you can run SQL queries and generate many graphs out of them. It is quite powerful and simple to use. Of course it does not have the flexibility of coding things directly, but for the basic use cases it is really fast.

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This was once hosted on Tumblr with the intention to become my personal blog where I would add things I was working on or learning. It never got passed a few entries with very outdated code (somethings not even valid today). I have decided to use GoHugo, and hosting it on Firebase that you get HTTP2 and other goodies for free. Hence I have decided to remove the old content and not bother to move it here.

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