The biggest FOSS/OSHW event in Bulgaria – Open Fest is 3-4 of November

Screenshot from 2018-10-11 08-20-10

Our favorite Open Source event – OpenFest is approaching. Every time I go there I do wonder how small Bulgaria attracts so many people there – thousands of people meet together. Probably the answer is that IT is developing very well and lot of people in Bulgaria work in IT industry.

I’m really pleased to announce that my proposal to talk about LoRa/TTN/LoRaWAN myths, possibilities, applications and limitations is approved! I will try to compare all popular LPWAN solutions, why LoRa is leading there (hint: open source 😉 ) and how you can calculate your power requirements, link budged etc to make sure your application will work with years on battery.

Are you ready for OpenFest 2016? We will have the already traditional Soldering Workshop there – The GHOST of Open Source Hardware is waiting for you!


Tomorrow is Open Fest 2016 in Sofia! The is similar to FOSDEM yearly meeting of thousands of people in Bulgaria, who care about the open source technologies.

The program is here:

Beside the talk about our progress on the OSHW Laptop , we will have the traditional FREE Soldering Workshop there.

For this purpose we created special PCB named The GHOST of the Open Source Hardware 🙂

Come and have fun, the board is very easy to assembly. It has two LEDs and PIC microcontroller with capacitive touch button made as the OSHW logo. As soon as you touch it the GHOST ‘eyes’ start to glow slowly.

The PCB has pin so you can attach it to your cloths as badge. On top there is standard Microchip ICSP connector, so later you can modify the code up to your taste.

We will have limited number of soldering irons with us, so if you have your own, bring it with you to speed up the assembly and not make tails of people waiting to solder their kit.

OpenFest 2015


There are two events during the year which we never miss – Fosdem and OpenFest!
These are the places you can meet many people who work and appreciate the open source culture and technology and are always in our agenda for “must visit”.

OpenFest 2015 was last weekend in Sofia. As allways it was over crowded, noisy and great!

Lectures were running in three halls, and three workshops were running all day long in fourth hall.

We made SMD PCB assembly workshop and teached how to make binary watch. You can see from the pictures this was interesting even to small kids, but also to their parents.





We also had lecture for the Internet of Things firmware for ESP8266.


This beautiful girl is not Olimex’s employee just signs in the pauses between the lectures 🙂

You can see on the first slide our new WiFi-Switch device with two 10A/250VAC relays which can fit inside normal power sockets as it’s only 40x35x12 mm.

And here is setup which displays twitter messages with #openfest15 hacktag, measure temperature, drive RGB LEDs, read fingerprints and open close doors with ESP8266-EVB



Specially for OpenFest we made wireless ESP8266 LED matrix badges and unintentionally made stress test of OpenFest wireless network as we forgot to disable by default the ESP8266 AP mode, so people had hard time to search for OpenFest APs as people were hanging around with EPS8266 badges which were showing up to people devices as WIFI hot spots :))



…and this is rare mix of traditional old Bulgarian dressing (with gun and knife in the belt) together with WiFi badge, walkie-talkie and cell phone next to the gun and knife 😀


This is picture of OpenFest closure, kudos to all 60 volunteers and organizers:


EDIT: here are some pictures taken during the OpenFest setup by the organizers

OpenFest 2015 is 7 and 8th of November in Sofia

Screenshot from 2015-10-29 12-05-59

Next weekend in Sofia will be held the biggest event for Free/Open Source technologies in Bulgaria – OpenFest which is run every year since 2003.

Olimex is approved for talk and workshop yay!

The lecture is in Saturday at 17.00 o’clock and we will show what we have been working mainly this year:

“Physical computing and IoT with Open Source Software and Hardware”.

We will demonstrate how easy is to connect physical objects to Internet with our new ESP8266 boards, and our plug and play firmware which recognizes the UEXT modules connected to ESP8266 like: electricity metering, LED displays, Fingerprint sensors, door locks, relays, buttons. etc. We will shop how to display Twitter messages on LED matrix display, how to make door lock with fingerprint sensor, how to implement DO button for IFTTT directly with ESP8266 by secure connection with 2048bit encryption, and how to connect and switch loads and measure what energy they consume.

Specially for Open Fest we made our new WiFi enabled LED 8×8 badge. It contains ESP8266 and can be programmed to do lot of stuff, like to display all tweets with hashtag #openfest2015 or to display what are the lectures which run now and in which rooms by connecting to Open Fest program web page and extracting the necessary info.


Needless to say WiFi Badge is OSHW and all software project sources will be on GitHub (sorry still work on the software and can’t upload yet, we will do this early next week keeping the good developer’s traditions everything to be complete and debugged in the last minute 😉 ).


As you can see all ESP8266 GPIOs are exposed on this badge so it is good also for development board, power supply is done with single 1.5V AA battery only!

The workshop will be about SMD component soldering, we will bring some Binary Watch Kits with us and teach you how to solder your own Binary Watch. These who already have been at TuxCon do remember these watches:


Looking forward to see you there 🙂

Open Fest 2014 and Hardware Hackathon with Adruino and Simon game


Open Fest is the biggest event for Open Source technologies in Bulgaria. This is the ultimate must visit event in the agenda of all Open Source enthusiasts in Bulgaria.

This year was our third time at Open Fest and the impression is that every next year it becomes bigger and bigger!

OpenFest is free to participate and managed by group of Open Source Enthusiasts totally on volunteer basis, instead to make money from this event they do the opposite they put their own money just to see at one place similar minded people and to make it one big fest.

You can’t imagine how friendly and spiritual is this event, celebration of the freedom in technology in software in hardware, the organizers even provide free breakfasts and coffee for everyone who come 🙂 how cool is this?

You can judge that the event grows indirectly by the number of the sponsors who join it and every year the number of sponsors increase.


The halls now are small and can’t accomodite all the people who want to hear the lectures and next year probably some bigger space need to be found for this event as current location is already too small.


I had a talk for Programmable Home, presenting what we are working now on to make home automation easier. Two years ago at Open Fest 2012 I had lecture about Open Source Hardware and Business and when I asked who knows what OSHW is there were just couple of hards which rise, this year on the same question more than 1/3 of the hall rised their hands, it’s good to see people get more aware of Open Source Hardware.

OF16 OF17 OF18 OF19

The video is now online.

We also ran the traditional Hardware Hackathon, this time we had the Pinguino FOSDEM edition Arduino boards for assembly and the more advanced Simon game.

Soon our spot become magnet for interesting people and sweet small talks about Electronics, DIY, OSHW etc.

Time was flying so fast we couldn’t realize when it become 18.00 o’clock and the guards came to drive us out as they had to lock the building 🙂

Meantime there were quite of interesting lectures running like the Software Defined Radio and RTL by Harald Welte:


Or the application of Open Source Hardware and Software in the Mining Industry by Noac Engineering:



needles to say the heart inside this complicated system is OSHW A20-OLIMEXINO-MICRO 🙂


Svetlin Nakov lectures are always interesting, he is trying to break the obsolete education model in Bulgaria by running free and quality education in his private Software University. How he makes money out of this? Two ways: first – if you want official exam documents you pay small fee, second – the Software companies pay him well for the graduated students, so people can learn for (almost) free and then if they perform well on the exams they get good paid job. Svetlin is quite a mix of good ideas and the ability to present them well while making entertaining show. We need more people like him!



OpenFest 2013 and the Open Source Hardware


To be two days together with hundreds of people who share your values and view on the open source technology – NICE!

To open the event with full Hall and people even sitng on the floor just to hear your presentation for Open Source Hardware – GREAT!

To see the big smile on the face of people who never used to touch soldering iron, but built their first Arduino themself and programmed their first Blink LED program – PRICELESS!





OpenFest 2013 was two days event last weekend where hundreds people all around Bulgaria meet together and share their experience in number of talks.

I opened the even with my presentation for the Open Source Hardware, tried to explain what is Open Source Hardware, (as many of the people were familiar only with free / open source software), what is my motivation to do Open Source Harware, what are the differences between open source hardware (OSHW) and Free/Open Source Software (FOSS) and why others should join and do Open Source Harware too.

The slides are available here. Soon the video of my talk will be put online by OpenFest organizers.

Both days in the lobby of OpenFest were running Hardware Hackathon where we provide 100 OLIMEXINO-85 kits, anyone who wanted could participate and solder his own Arduino which then to test and program and take home free of charge. People with no any knowledge in electronics and soldering came and out of 100 kits just 2 were broken, all other 98 were successfully assembled!

I admit I didn’t expect such big interest in Hardware on so traditionally “FOSS” related event. From 10.00 till 17.00 there was always crowd of peoples around the tables, waiting on tail to take seat with soldering iron as we got only 4 with us, there were even few people who came with their own soldering irons from home in their backpacks.

Open Fest 2013 program is available


Open Fest organizers has published preliminary schedule for the speaks:

Foreign guests this year are:

  • Karanbir Singh – CentOs
  • Mani Sarkar – Java User Group London
  • Tiberiu C. Turbureanu – Firefox OS

I’m going to speak Saturday 11.15-12.00 – the title is “Open Source Hardware from Bulgaria” and will present OLinuXino roadmap and our other Duino boards including the new NANO and some new boards which are in development.

There will be Harware Hackathon during the OpenFest sponsored by Olimex. Every one who want to learn how to solder will have possibility to build by himself Arduino board with PTH components which then to take home 🙂

There will be prizes for these who assembly the board fastest.