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Tomorrow is an announcement of EdgeDB 2.0, and I realized that I’ve never shared my experience with it, and it’s been more than a year since I switched every project I could to EdgeDB. So here is a short post on it. 
 What is EdgeDB? 
 It’s an open-source relational/graph database built on top of Postgres. 
 Unlike many other databases, it doesn’t reinvent the…
It’s 3AM of 4th of March, 2022, but it’s just “the eighth day” for Ukrainians. We don’t know what day it is any more because every day lasts at least ten lives. 
 I was in Kyiv a day before the war started. On Wednesday, I flew to Estonia for a regular business trip. I had only a small backpack and planned to return in a few days. 
 I’m safe, but…

 The newest release of Go – Go 1.13 – finally introduced full support for Go Modules – brilliant and long-awaited solution for built-in dependency versioning problem. Modules now enabled by default, and virtually make GOPATH obsolete. 
 Technically speaking, GOPATH is still supported, and Go 1.13 Release Notes uses term “ GOPATH mode ” (as being opposite to the “ modules…
This is a blog version of the talk I gave at GopherCon Europe 2019 (Canary Islands Edition) , where I shared my thoughts on why Visual Programming Languages have failed and revealed for the first time my experiment on visualizing Go code. 
 
 I could dive in straight into the project, but I do believe to truly appreciate it, I have to explain the thought line behind it first. 
 It…
I’ve recently discovered Flutter – a new Google’s framework for mobile development – for myself and even had an experience of teaching Flutter basics to the person who has never been doing programming at all. Flutter is written in Dart – programming language born in a Chrome browser and then escaped to the console land – and that made me think “hey, Flutter could have been easily…
TL;DR In this article I’ll share my experience building an interactive 3D WebGL-based application for peer-to-peer messaging protocol simulation without writing any single line in JS. You’ll learn how GopherJS and Vecty framework can dramatically lower the complexity of building WebGL-enabled web apps in Go. 
 
 It’s often said “A picture is worth a thousand…
(source: Anders Sune Berg ) 
 In the previous article I’ve described a weekend project called txqr for unidirectional data transfer using animated sequence of QR codes. The straightforward approach was to repeat the encoded sequence over and over until the receiver gets complete data. This simple repetition code was good enough for starter and trivial to implement, but also introduced…
TL;DR: a weekend project for transferring data via animated QR codes, written in Go and using fountain erasure codes. The Go code is reused for mobile apps using Gomobile, and in a web application for automating testing QR codes parameters, built with GopherJS and Vecty framework. 
 
 I’ll share my experience building it, some code and benchmark results of using animated QR as a data…
On the last Golang Barcelona meetup we decided to try new format of conversation and after the talk started open discussion on logging, tracing and metrics. The idea was to encourage people to read a very nice blog post by Peter Bourgon on this subject - “Metrics, Tracing and Logging” and discuss it in a free format. 
 It went surprisingly well, and while most of the people were…
I used to think that misunderstanding interfaces in Go can lead, at most, to not very readable code and worse maintainability. From my observations misusing interfaces becomes visible usually during refactorings, where you questioning what this type or abstraction actually represents. But, at least, the code tends to work and it’s not buggy. 
 The bug 
 But here is the interesting…
TL;DR by learning internals 
 
 a gotcha is a valid construct in a system, program or programming language that works as documented but is counter-intuitive and almost invites mistakes because it is both easy to invoke and unexpected or unreasonable in its outcome
(source: wikipedia ) 
 
 Go programming language has some gotchas and there is a number of good articles explaining…
A couple of weeks ago I gave a talk at the largest Go conference, GopherCon , in Denver. It was the first time I attended GopherCon at all, and the first time ever I spoke in English in front of 1400+ people, and it was an absolutely incredible experience. Here is my story. 
 My journey to GopherCon started on a cold winter day in the apartments in the center of Odessa, Ukraine, where I was…
As Go community slowly moving towards established and well understood patterns and practices of dependency management, there are still some confusing moments. One of them is automating repeatable build process using containers along with using dependencies in private repositories. 
 Private repositories on Github are often is a source of confusion when using go get , but it has easy workaround…
You’ve probably heard that story about NPM community and LeftPad package, that broke thousands JavaScript projects worldwide. There was a nice follow-up article titled “Have We Forget How To Program” and one guy even created left-pad.io - Left-Pad As A Service web service. People got a lot of fun discussing this story. 
 I personally find this story amazing, because there is…
If you prefer video over blog posts, here is my talk on this at GopherCon 2016: 
 https://www.youtube.com/watch?v=KyuFeiG3Y60 
 One of the strongest sides of Go programming language is a built-in concurrency based on Tony Hoare’s CSP paper. Go is designed with concurrency in mind and allows us to build complex concurrent pipelines. But have you ever wondered - how various concurrency…
Over the years of existence of Go programming language, the articles with its critique was always popular, bringing a lot of discussion from both sides. Recently, Maksim Kochkin even created GitHub repo with curated list of articles complaining about golang’s imperfection. 
 So, is it true that ranting about Go flaws is a trend nowadays? With carefully gathered links in the repository…
Note: this post was originally written for the Go Advent 2015 series, but I discovered that a post with almost exactly the same subject (and even similar code!) already planned :) That’s amazing. 
 Golang is often used for writing microservices and various backends. Often these type of software do some computation, read/write data on external storage and expose it’s API via http…
I recently translated great article — Errors are values by Rob Pike — and we discussed it in our podcast Golangshow (in russian). One thing I was surprised about is that even experienced Go developers sometimes do not understand the core idea of that article. 
 Looking back, I remember my first impressions when I read it for the first time. It was similar to “It looks like Pike just adds some…
![](https://divan.dev/posts/gopath/"https://divan.dev/images/gopath.png")
![](https://divan.dev/posts/visual_programming_go/"https://divan.dev/images/vpl_cover.png")
![](https://divan.dev/posts/webgl_go/"https://divan.dev/images/go-webgl/demo.gif")
![](https://divan.dev/posts/fountaincodes/"https://divan.dev/images/fountain.jpg")
![](https://divan.dev/posts/animatedqr/"https://divan.dev/images/txqr_send.gif#center")