Citymobil — a manual for improving availability amid business growth for startups. Part 5

This is the final part of the series describing how we’re increasing our service availability in Citymobil (you can read the previous part here). Now I’m going to talk about one more type of outages and the conclusions we made about them, how we modified the development process, what automation we introduced.
7 tips how to deal with remote teams
A number of both large corporations and small companies having almost no staff is increasing. This is the impulse of new times that many call “uberization”. The phenomenon was named after Uber — one of the largest public-transportation companies whose drivers all are independent entrepreneurs aka freelancers. Such a structure allows Uber to work all over the planet through operating remote teams of drivers in dozens of cities simultaneously.
DO-RA: Preparing for Industrial Production

1. Transporting prototypes
The idea of the DO-RA project originated in March 2011 after a nuclear disaster on the Fukushima Daiichi nuclear power plant in Japan. This gadget was conceived as a personal dosimeter/radiometer working with eponymous software (DO-RA.Soft) on mobile platforms (iOS, Android, WP) as well as on desktop platforms—Windows/Linux/MacOS.
At the end of 2017, a tourist from China brought in his backpack ten long-awaited prototypes from the DO-RA.Q test batch. They were manufactured in China based on our design documents and then transported from Shenzhen to Moscow. By the way, the development of design documents was assigned to the largest Design Centre in Eastern Europe—the PROMWAD company. The documents were clear and plain—prepared in IPC format and written in proper English—to enable the automated production of electronic devices in a foreign country.
Citymobil — a manual for improving availability amid business growth for startups. Part 4

This is the next article of the series describing how we’re increasing our service availability in Citymobil (you can read the previous parts here: part 1, part 2, part 3). In further parts, I’ll talk about the accidents and outages in detail.
1. Bad release: database overload
Let me begin with a specific example of this type of outage. We deployed an optimization: added USE INDEX in an SQL query; during testing as well as in production, it sped up short queries, but the long ones — slowed down. The long queries slowdown was only noticed in production. As a result, a lot of long parallel queries caused the database to be down for an hour. We thoroughly studied the way USE INDEX worked; we described it in the Do’s and Dont’s file and warned the engineers against the incorrect usage. We also analyzed the query and realized that it retrieves mostly historical data and, therefore, can be run on a separate replica for historical requests. Even if this replica goes down due to an overload, the business will keep running.
How to make a perfect roadmap?
What is a coding bootcamp?
The goal of many bootcamp coding attendants is to move into a web development career. They do this by learning to build applications at a professional level – providing the foundation they need to build applications that are ready for production and demonstrating the skills they have to add real value to a potential employer.
Quality as Team's responsibility. Our QA experience
Disclaimer: This is a translation of an article. All rights belongs to author of original article and Miro company.
I'm a QA Engineer in Miro. Let me tell about our experiment of transferring partially testing tasks to developers and of transforming Test Engineer role into QA (Quality assurance).
First briefly about our development process. We have daily releases for client side and 3 to 5 weekly releases of server side. Team have 60+ people spitted onto 10 Functional Scrum Teams.
I'm working in Integration team. Our tasks are:
- Integration of our service into external products
- Integration of external products into our service
For example we have integrated Jira. Jira Cards — visual representation of tasks so it's useful to work with tasks not opening Jira at all.
How the experiment starts
All starts with trivial issue. When someone of Test Engineers had sick leave then team performance was degraded significantly. Team was continued working on tasks. However when code was reached testing phase task was hold on. As a result new functionality didn't reach production in time.
Going onto vacation by Test Engineer is a more complex story. He/she needs to find another Test Engineer who ready to take extra tasks and conduct knowledge sharing. Going onto vacation by two Test Engineers at the sane time is not an applicable luxury.
Top 7 qualities of an effective manager
Citymobil — a manual for improving availability amid business growth for startups. Part 2

This is a second article out of a series «Citymobil — a manual for improving availability amid business growth for startups». You can read the first part here. Let’s continue to talk about the way we managed to improve the availability of Citymobil services. In the first article, we learned how to count the lost trips. Ok, we are counting them. What now? Now that we are equipped with an understandable tool to measure the lost trips, we can move to the most interesting part — how do we decrease losses? Without slowing down our current growth! Since it seemed to us that the lion’s share of technical problems causing the trips loss had something to do with the backend, we decided to turn our attention to the backend development process first. Jumping ahead of myself, I’m going to say that we were right — the backend became the main site of the battle for the lost trips.
Business processes. BPMN model extraction from the document. Part 1

The analyst for the project faces a rather time-consuming task which is at the same time a routine one as well. It doesn’t have many means of automation at present. According to the analysis of modern means of business process modelling, even such well-known applications on the market as Enterprise Architect, ARIS, Bizagi Modeler do not have any support mechanisms for business process model building in their text description.
This article is focused on the BPMN model extraction from the document.
10 critical skills every DevOps engineer
What is DevOps and Why is it important?
DevOps is the combination of Development teams and Operation teams in order to create a business with traditional software development practices. DevOps gaining popularity at a rapid pace. Let's see how DevOps helps the delivery of Software products.
When the development and operational teams are inseparable silos, it makes development life cycles longer due to lack of communication and cooperation between two teams. By merging those two we can make software development shorter cycles.
DevOps is not a profession. It's culture. It builds teams and makes engineers work for a common goal rather than individual performances. This leads to better collaboration and increased efficiency.
More importantly, DevOps reduces rollback failures, Rollbacks and give time to recover. The main characteristic of DevOps. This helps to find bugs and failures quickly giving rise to rectify bugs or recover from failures.
Citymobil — a manual for improving availability amid business growth for startups. Part 1

In this first part of an article series «Citymobil — a manual for improving availability amid business growth for startups» I’m going to break down the way we managed to dramatically scale up the availability of Citymobil services. The article opens with the story about our business, our task, the reason for this task to increase the availability emerged and limitations. Citymobil is a rapid-growing taxi aggregator. In 2018, it increased by more than 15 times in terms of number of successfully completed trips. Some months showed 50% increase compared with the previous month.
The business grew like a weed in every direction (it still does): there was an increase in server load, team size and number of deployments. At the same time the new threats to service availability emerged. The company faced a task of the most importance — how to increase availability without compromising company growth. In this article, I’ll talk about the way we managed to solve this task in a relatively short time.
Technical debt leading to a company crisis

Estimation of VaR and ConVaR for the stock price of the Kazakhstani company
The last decades the world economy regularly falls into this vortex of financial crises that have affected each country. It almost led to the collapse of the existing financial system, due to this fact, experts in mathematical and economic modelling have become to use methods for controlling the losses of the asset and portfolio in the financial world (Lechner, L. A., and Ovaert, T. C. (2010). There is an increasing trend towards mathematical modelling of an economic process to predict the market behaviour and an assessment of its sustainability (ibid). Having without necessary attention to control and assess properly threats, everybody understands that it is able to trigger tremendous cost in the development of the organisation or even go bankrupt.
Value at Risk (VaR) has eventually been a regular approach to catch the risk among institutions in the finance sector and its regulator (Engle, R., and Manganelli S., 2004). The model is originally applied to estimate the loss value in the investment portfolio within a given period of time as well as at a given probability of occurrence. Besides the fact of using VaR in the financial sector, there are a lot of examples of estimation of value at risk in different area such as anticipating the medical staff to develop the healthcare resource management Zinouri, N. (2016). Despite its applied primitiveness in a real experiment, the model consists of drawbacks in evaluation, (ibid).
The goal of the report is a description of the existing VaR model including one of its upgrade versions, namely, Conditional Value at Risk (CVaR). In the next section and section 3, the evaluation algorithm and testing of the model are explained. For a vivid illustration, the expected loss is estimated on the asset of one of the Kazakhstani company trading in the financial stock exchange market in a long time period. The final sections 4 and 5 discuss and demonstrate the findings of the research work.
Ambient music and its effects on writing code

Homo laborans and music
Today the effect music has on all living creatures, humans included, is a fairly well-researched topic. It’s been common knowledge for a while that classic music helps people to calm down and relieves stress, while high-energy tunes of various genres can make your workout results way more impressive.
Plenty of scientific papers have been published that explore this phenomenon, especially by medical researchers and psychologists (use of music as a part of treatment plan, the way different organs respond to it, etc.). Naturally, many of those you gotta take with a grain of salt as there’s always the risk of crossing the line into pseudoscience, but there’s no shortage of reliable sources that confirm that link.
You don’t need to go further than Habr to find plenty of insightful articles that talk about the influence music has on a working environment and attention span of the workers. But this particular one has a slightly different intent.
Microsoft expands Azure IP Advantage Program with new IP benefits for Azure IoT innovators and startups
At Microsoft, we’re investing in helping our customers as they move to the cloud. We see an opportunity to help support companies in this changing environment by bringing our security, privacy, compliance and intellectual property assets and expertise to bear in order to help them be more successful. We’re excited to now take an additional step that expands innovation protections.
Today, we are pleased to announce the expansion of the Microsoft Azure IP Advantage program to include new benefits for Azure IoT innovators and startups. We first announced Azure IP Advantage in February 2017, to provide comprehensive protection against intellectual property (IP) risks for our cloud customers. A trend we saw at the time – and one that continues today – is a growing risk to cloud innovation from patent lawsuits. Last year, we joined the Open Invention Network (OIN) and the License on Transfer (LOT) Network to help address patent assertion risk for our customers and partners.
This article in our blog.
Physical unclonable functions: protection for electronics against illegal copying

Source: The online counterfeit economy: consumer electronics, a report made by CSC in 2017
Over the past 10 years, the number of fake goods in the world has doubled. This data has been published in the latest Year-End Intellectual Property Rights Review by the US Department of Homeland Security in 2016 (the most current year tracked). A lot of the counterfeiting comes from China (56%), Hong Kong (36%) and Singapore (2%). The manufacturers of original goods suffer serious losses, some of which occur on the electronics market.
Many modern products contain electronic components: clothes, shoes, watches, jewellery, cars.
Last year, direct losses from the illegal copying of consumer electronics and electronic components in the composition of other goods were about $0.5 trillion.
How to solve this problem?
How to quickly prepare for a job interview with questions on algorithms and technologies
It doesn't really make sense for an employer to ask the applicant about traditional programming technologies. That is why I'm going to tell you how to prepare for an interview in only one narrow area related to information processing languages, namely, the processing of long integers(long arithmetic) and the identification of information properties of real world objects, which are described in long integers.
Hubs
Authors' contribution
alizar 36022.3marks 21019.2nmivan 12793.0Erwinmal 12250.0semen_grinshtein 9018.7Milfgard 7557.0slava_rumin 6613.0ancotir 5825.0aleksandrit 5794.0ru_vds 5757.9