Integral Review

Welcome to my personal blog! I use it to share what I'm currently learning or thinking about, usually on topics related to technology, business, and health.

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Thoughts on rent control and better alternatives

June 08, 2021
Rent control is a recurring idea in politics. And for good reasons: In some cities, housing prices increase to untenable levels for most. Berlin was one of those cities. For decades, it was known in part for its affordable cost of living. But its rise in popularity led rents to sharply. Until last year, when a strict rent control law enacted.

A guide to building a blockchain & cryptocurrency from scratch in Ruby

April 29, 2021
Even putting aside the hype around cryptocurrencies, it’s impossible to deny how big an innovation they are. Computers and the internet brought us free and unlimited copies of data: You can create a file and send it to thousands of people for free. The invention of blockchains brings scarcity to the internet: If you have a coin, only you have it.

A minimalist free commenting system built with Cloudflare Workers

April 22, 2021
It is still possible to build interactive features on the web without overengineering them. At least, that’s what I wanted to prove to myself when adding a commenting system to this blog.

10 risks and challenges you should be aware of in P2P Lending

April 04, 2021
P2P Lending is a recurring topic in the Financial Independence community due to its relatively good track record (at least in Europe in the last couple of years). After losses, investors are regularly above 10% return per annum—an incredible performance compared to other alternatives in Europe.

Introducing my latest project: VocalBird

May 08, 2020
Those who use voice messages on apps such as WhatsApp or iMessage know how efficient and personal they are.

Getting more productive is the most human thing you can do

February 16, 2020
If you create an application that streamlines a regular hour-long operation in a two-minutes one, you might have a successful company on your hands. You’ve created value by saving time (and therefore money) to a business, and your client thanks you by giving you a share of the savings.

Security needs the best UX

January 26, 2020
Keeping data secured online is cumbersome. Nothing beats in simplicity: reusing the same short password, avoiding IP filtering, sharing passwords in clear text, and not having 2FA. Business owners and engaged employees will work through some hoops, knowing what’s at stake. But not everyone will care, which will create vulnerabilities.

A system to be calm

December 29, 2019
Our default approach to productivity is to think of increasing our output. How can we avoid distractions? The afternoon slump? Need less sleep?

Business opportunities well-funded startups cannot take from bootstrapped businesses

October 07, 2018
When well funded, growing, continually hiring startups are in a market, it’s not necessarily bad news for bootstrapped companies. After some time, a pattern emerges on their pricing pages: High prices with a lot of emphasis on reaching out to the sales team — Or even no publicly available pricing at all.

Gaming the NPS

June 13, 2018
If for your job, you get a bonus over a certain NPS score, then here is how you can game the system to get it.

Not raising funds to stay small and happy

December 23, 2017
“Any plans to raise funds?” is a question I get a lot. Here are a few of the reasons why we intend to stay bootstrapped.

Tools distract us from building

May 22, 2017
When building a SAAS, every week comes with opportunities to use news tools. Maybe we need to add a new database or to track a new project. Those are almost never first-times. You most likely already have a database currently online.

HTTPS is hurting users far away from your servers, and what to do about it

March 10, 2017
Lately, we’ve been told HTTPS is finally faster than HTTP. Mostly because of HTTP/2’s multiplexing. In this post, I want to highlight an issue we rarely think about with HTTPS: the slowdown it implies for users far away from your servers. Since we’re usually on the same continent as our servers, we never get to think about this.

Super simple worker pools in Go using channels

February 28, 2017
I’m sure you’ve had to write some code where you have a few hundred thousand items and need to do some work on them. Performing the jobs serially would be too long. And launching everything at once with goroutines isn’t possible because of some other limitation. You need a worker pool.

How to disable some of your website’s endpoints in seconds

January 06, 2017
They are cases when you need to disable some endpoints of a website as fast as possible. For example, in the case were an issue on an endpoint is causing all of your website to go down. Or because you need to limit the traffic load quickly by sacrificing parts of the API, instead of losing everything.

Lessons learned from our Security Bounty Program

December 09, 2016
A few weeks ago we launched our security bounty program. This was a great decision and we should have done it earlier. Over the last few weeks, we learned some key lessons.

Getting hired as a remote worker

October 26, 2016
Over the last few months, I got to do about a hundred interviews to hire new members of our remote team. Here are the most frequent issues I experienced. Most of them seem obvious, but you would be surprised how frequently they happened.