It seems computer security is as hot as ever topic. One of ideas that constantly float around is that systems will never be secure, that there will always be someone who is going to whistle nuclear launch codes magically with mystical juju’s called zero days. To me that sounds like anti vaxxer propaganda in modern pandemic like if you get vaccine and you are pregnant you will start to bleed and get cancer like the cancer you get from wind generators. Its similar to communism.

It seems to me that many of these zero days will not be viable in…


Usually European schools offer decent education. Although it is not top of the food chain Stanford or what not American it is not bad. Like food at mensa. I mean we need to be honest, can’t be grumpy about it and ungrateful.

What in general pan European school system lacks is like one course on business. Some type of product manage type of thing. Many people spend time doing tech. They get technically fluent. There is no issue there. Issue then comes how come thats it.

I feel people need some type of business manage type of things to get…


Once we develop apps usually we pick a framework and set of tools. Like the one below. We have usually Lodash inside and bunch of other things.

One of things that stand out after prolonged usage is that some of these are used more than the others. Some make you more productive while some are standard brushes or similar. I keep feeling that for example rxjs and lodash are these hard to replace tools now. We saw reactive programming before rxjs with older projects like baconjs. Few people used it back then to drive whole application forward. Now with omnipresence…


I can’t remember how many times I searched for how to get certbot get certificate with docker and its always somewhere hard to find :-D

Here it is in more convenient place stashed so one can copy paste

docker run -it — rm — name certbot -v “/etc/letsencrypt:/etc/letsencrypt” -v “/var/lib/letsencrypt:/var/lib/letsencrypt” -p 443:443 -p 80:80 certbot/certbot certonly — standalone — preferred-challenges http -d mysite.com

This will put certificates in local drive and wont require intervention from command line.


Why I think rancher is something to roll with when doing things on on prem environments?

When one wants to juggle various services and containers one few years ago had little but few alternatives. They all looked like really good but once you actually try them on its like you get failure here or there and it will take time to get them up and running without trouble. …


JavaScript is today very dominant language. It is everywhere and its going bigger. One could see its popularity grow and compete and overpower more traditional languages like Java. Ecosystem grew and grew more mature.

TypeScript came as advertising to solve problem of large codebases by improving productivity in such environments by adding type system. The promise of TypeScript is to have JavaScript while giving user more instruments to deal easier with problems in setups that are encountered in large codebases that have multiple teams collaborating and interfacing. It is great at that. …


JavaScript is progressing to be king of the hill among programming languages. Before it was frowned upon by people and underdog of programming languages it grew omnipresent and evolved to dominate.

One of the reasons I’d argue is most contributing to JavaScript becoming so popular is the ease with which one can iterate and make progress.

This might look as some reason that is like side observation but honestly when I look at some problem and I’ve programmed for some time now one of immediate things that pop to mind is just how easy and quick things can happen with…


I open twitter and there is 10x everything. To try to attach my blog on the trend I’ll write something too :-D .

Here is some words I stole from a book and paraphrased. We are all different. Some are prettier than the others, some play Starcraft better, some play chess better, some win games of chance more than others, some have bigger biceps, some are poor or smarter than others, but we all come with a free will to pick things for which we are bad or good. We are in this world to pick or to trade, today…


Here is some quick and dirty video editing that one can use to for example submit app preview to app store or meet constraints on video like duration and resolution.

If we want to rescale our video we could do something like

ffmpeg -i preview.mov -vf scale=886:1920 video_640.mp4

if we want to strip sound we could

ffmpeg -i video_640.mp4 -an -vcodec copy output_file.mp4

if we want to add sound we could

ffmpeg -i output_file.mp4 -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=44100 \\n-c:v copy -shortest output.mp4

if we want to change FPS we could do following

ffmpeg -y -i output.mp4 -c copy -f h264 output.h264

followed by

ffmpeg -y -r 30 -i output.h264 -c copy output3.mp4

now that we changed FPS video might be long

lets speed it up lets say 4 times

ffmpeg -i output3.mp4 -filter:v “setpts=0.20*PTS” output4.mp4

It takes a few google searches but here it is sublimed.


You might want to bundle certificate and private key together to be able to sign things and googling takes bit more than expected. Here is rundown at one place

Lets generate key for certificate by running following

openssl genrsa -out mysite.key 2048

Lets obtain signing request with this new key just generated

openssl req -new -sha256 -key mysite.key -out mysite.csr

Now to be able to have it in p12 format we should convert certificate we got from signing authority to PEM

openssl x509 -inform DER -in mysite.crt -out mysite.pem -outform PEM

Now to tie key and certificate together into one certificate that one can use to sign things

openssl pkcs12 -export -clcerts -inkey mysite.key -in mysite.pem -out mysite.p12 -name “My Site”

enjoy :-)

Nikola Mandic

computer user

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