Author Archives: George Valentin Voina

#OpenSSH private keys with old PEM format

Starting from openssh 7.8 the default format for private keys has changed from PEM to OpenSSH: That means that private keys generated with the referenced command: (ssh-keygen -t rsa -b 4096) are no longer generated as PEM format. Lot’s of online services do not accept this format yet CircleCI, GitHub are some of the services… Read More »


Acronyms of a #VC for #fintech people

When you start reading lots of VC tweets and blog posts is easy to get confused by the deluge of acronyms they use. The following are the basic definitions for the most important acronyms. CAC = Customer acquisition cost TAC = Total acquisition cost LTV= Lifetime value TAM = Total available market YoY growth =… Read More »

Disable core dumps in #Linux

Systemd doesn’t completely control whether core dumps are made or not. It mainly determine where such dumps go, and whether they should take up space or not. It may prevent some user space core dumps, but not all. With “Storage=none”, they can still occur and are registered by journald, but they don’t take up disk… Read More »

Libraries #golang : Inter Planetary File System client

In all this talk of distributed systems the Interplanetary File System is a fun practical subject. Obviously golang should be part of that. According to Wikipedia: The InterPlanetary File System (IPFS) is a protocol and peer-to-peer network for storing and sharing data in a distributed file system. IPFS uses content-addressing to uniquely identify each file… Read More »

Connect to github with ssh key

This is a straight forward list of steps to connect to github with a ssh key instead of user/password. I am using Linux on my development machine so things are quite easy with ssh. STEP 1: Create a ssh key # ssh-keygen -t rsa -b 4096 -C “” STEP2: Add the key to the authentication… Read More »

Ferengi Rules of Acquisition vs #Fintech

Like a true Star Trek fan I have my lists: this is one of most complete compilation of the “Ferengi Rules of Acquisition”. I swear they apply in the real Business World, almost to the letter 🙂 Sadly we can see behaviours that follow the rules also in #Fintech, Banking and Social Media companies. So… Read More »

Banking 2.0 or the online revolution #Monese #fintech

My new collector passion latter seems to be about new challenger bank accounts 🙂 Yes, now is the turn for Monese. My third online bank after #Revolut and #TransferWise. As I already mentioned in a previous post , banking 2.0 is here. Enrollment is very easy with a video based verification and with a simple… Read More »