What’s behind leboncoin

leboncoin tech
leboncoin tech Blog
3 min readDec 8, 2017


By Jean-Louis Bergamo (Infrastructure Director)

Tech team

When people think about leboncoin’s website, they imagine, because of the design, that it is a website made by only two guys in their parent’s garage.

OK, for a long time leboncoin had a dirty yellow background and its features were only : post ads, search ads, contact sellers and, … that’s it.

leboncoin’s old homepage

On one hand it’s what made our success, and it’s what our users like about leboncoin (and made us win the battle against some other big US ads companies). On the other hand, even if our features were poor, at the size of leboncoin (one of the 5 most visited websites in France), it is really challenging to make it work and, above all, make it work fast.

You may have noticed that leboncoin’s look changed recently (both on the website and mobile apps) and some great features were added, or will be added soon, to it : search nearby, saved searches, alerts, internal messaging …

OK, it’s still a simple website, as in, easy to use for our users, but all this can’t be done by only two guys in a garage. :-)

leboncoin’s new look

We are now around 150 techs people (in a company of around 600 now) to maintain our beloved website and apps every day. It implies usage of some great technology (mostly open-source) and quite a bit of in-house developed piece of software. For example, did you know that leboncoin uses its own indexer and search technology to answer several hundreds of millions requests per day ? It’s quite challenging to stay fast with more than 29 millions ads (at the time of writing this article) into our database and with more than 14 millions unique visitors per day.

Want some others numbers on leboncoin ? OK let’s go:

  • As mentioned before, leboncoin is among the top 5 of most visited websites in France. This means more than 26 millions unique visitors per month, which is good, but not good enough, because we aim to reach every French people within a year.
  • During peak hours we have more than 150,000 requests per second on our servers (including web pages, images and static content). This is more than 14 Gbit/s of internet traffic.
  • leboncoin is running its own infrastructure (including network) with more than 600 servers running to answer all of your requests. Some of them have 160 cores and 2 TB of RAM !
  • Some relational databases are around 10 TB of data. And, yes, PostgreSQL is strong enough to handle heavy DBs like this. :-)

You want to know more in depth about leboncoin ? You want to read what our DevOps, front-end developers, back-end developers Android/iOS developers, Data developers, QA engineers and all of our technical staff have to say ? Well, come back to this blog from time to time, because we will write about the heart of our technology.