Lachezar is available for hire
Hire LachezarLachezar Tsanov
Verified Expert in Engineering
Software Developer
Sofia, Bulgaria
Toptal member since October 27, 2021
Bio
Lachezar is a senior software developer with nine years of experience working on projects with different maturity and team sizes. Over the last years, he's focused on front-end development with Angular, React, and Ember. Lachezar excels at creating products from scratch, fitting into already established teams with a high-quality culture like Bosch IoT, and is also committed to working at high-paced startup environments like Kanbanize.
Portfolio
Secureframe, Inc.
React, GraphQL, Apollo, Search, Ruby, Elasticsearch, Cypress, Python 3, Celery...
Avallain
JavaScript, Ember.js, React, Ruby on Rails (RoR), CSS, Material UI, CSS3, HTML5...
Bosch IoT Suite
Angular, MongoDB, Plotly, Leaflet, Scrum, HTML5
Experience
- CSS - 9 years
- Ruby on Rails (RoR) - 6 years
- TypeScript - 4 years
- Angular - 4 years
- Python 3 - 3 years
- React - 2 years
- MongoDB - 2 years
- GraphQL - 1 year
Availability
Part-time
Preferred Environment
Linux, MacOS, Git, RubyMine, TypeScript
The most amazing...
...experience I've had was being the first developer and the core team member of a successful startup that now has over 40 employees.
Work Experience
Full-stack Engineer
2022 - PRESENT
Secureframe, Inc.
- Improved the React component library with Storybook. Added experimental automation features to check if the Storybook components are functional.
- Elevated the front-end testing environment for the tests to be easily written and data to be easily mocked.
- Leveraged Elasticsearch and Searchkick to have scalable, maintainable, and strongly typed searches on various data.
Technologies: React, GraphQL, Apollo, Search, Ruby, Elasticsearch, Cypress, Python 3, Celery, Asyncio, Sentry, Docker, PostgreSQL
Senior Front-end Engineer (Contract)
2019 - 2022
Avallain
- Worked for National Geographic to create an online and offline cross-platform app for teachers to manage content and students. I built the front end with Ember.js and Ember Data and the native apps with Qt.
- Acted as a product team member to build UI features for teachers and students using React and MUI.
- Created more than six mini interactive games by heavily using CSS animations.
Technologies: JavaScript, Ember.js, React, Ruby on Rails (RoR), CSS, Material UI, CSS3, HTML5, Python 3, Celery, Asyncio
Front-end Engineer (Contract)
2018 - 2019
Bosch IoT Suite
- Worked at Bosch IoT for one of their biggest customers in the food industry. Aggregated real-time data from devices by writing MongoDB queries and visualizing them with Plotly.
- Used interactive maps from LeafletJS to report real-time data of more than 1,000 stores over Europe and trace faulty devices.
- Created a playable graph that visualizes data detected by car sensors within a given time frame.
Technologies: Angular, MongoDB, Plotly, Leaflet, Scrum, HTML5
Software Engineer
2015 - 2018
Meetic Group
- Led the rewriting of the mobile app from jQuery mobile to AngularJS and Onsen UI, debugging Cordova issues.
- Performed a significant role in rewriting the desktop and mobile app to a single responsive one using Angular2+.
- Set up the test environment using Karma, Jasmine, and Protractor and wrote tests.
- Implemented various A/B tests and extended the API.
Technologies: AngularJS, Angular, Onsen UI, Ruby on Rails (RoR), Cordova, Jasmine, Cucumber, Elasticsearch, Ruby, HTML5, CSS3
Software Engineer
2014 - 2015
Freelance
- Built a website for booking travel packages and developed a module for partial payments in Magento, performing integration with third-party booking services.
- Created an online store for selling clothes with extreme front-end customization using Magento. This project took two months to be developed, from start to production.
- Developed an Android app for IPTV, using and customizing the Stalker Portal middleware to manage IPTV users, subscriptions, and channels. Supported the Android app development and debugging.
Technologies: Magento, jQuery, HTML
Software Engineer
2012 - 2014
Kanbanize
- Implemented most of the reports and statistics modules on the front and back end, including an in-app chat, an auto-updating module for an on-premise version, and many more.
- Developed a PHP module using C and C++ to handle access and licensing for the on-premise version of the tool.
- Implemented Google Drive integration, overcoming limitations of Google APIs not allowing wildcard domains by using a proxy, cross-iframe communication, and comping with CORS.
- Integrated the tool with LDAP and Active Directory for the on-premise version.
- Helped the company to secure VC funding and pitched the tool at mentor and networking meet-ups.
- Mentored three new employees and worked closely to distribute work among them.
Technologies: JavaScript, PHP, jQuery, CSS, Google APIs, Agile, Kanban, HTML
Experience
National Geographic Learning Online Practice
https://learn.eltngl.com/A general English program that empowers learners to achieve their language goals.
I was a front-end developer. I built online and offline cross-platform applications for teachers and students using Ember.js and Ember Data. I also created the assignments module of the application in React and built more than six mini-games with heavy use of CSS animations.
I was a front-end developer. I built online and offline cross-platform applications for teachers and students using Ember.js and Ember Data. I also created the assignments module of the application in React and built more than six mini-games with heavy use of CSS animations.
Trading Bot
I created a profitable crypto trading bot around unique trade signals using different strategies:
• Anomaly predictions using machine learning models
• Anomaly detection within milliseconds
• Cross-platform trading
• A high-frequency market maker
• Anomaly predictions using machine learning models
• Anomaly detection within milliseconds
• Cross-platform trading
• A high-frequency market maker
Bosch IOT
https://bosch-iot-suite.com/A project that gathers, transforms, and interacts with data from IoT devices.
I was an Angular developer, and as part of the product team, I had to implement data pipelines where users could configure what would happen when their data stream emits.
As part of one of the customer-dedicated teams, I created a dashboard with differently aggregated data by writing MongoDB queries and visualizing them with Plotly.
I was an Angular developer, and as part of the product team, I had to implement data pipelines where users could configure what would happen when their data stream emits.
As part of one of the customer-dedicated teams, I created a dashboard with differently aggregated data by writing MongoDB queries and visualizing them with Plotly.
Skills
Libraries/APIs
React, jQuery, Google APIs, Leaflet, Node.js, Plotly.js, Asyncio
Tools
Celery, Git, RubyMine, Cucumber, Plotly, Ngrok, Babel, Webpack, Sentry
Languages
JavaScript, CSS, TypeScript, HTML5, HTML, CSS3, GraphQL, Python 3, Ruby, PHP, SQL, Python
Frameworks
Angular, Redux, Cypress, Ruby on Rails (RoR), Ember.js, AngularJS, Onsen UI, Jasmine, Material UI, Express.js, Jest
Paradigms
Agile, Test-driven Development (TDD), Kanban, Scrum
Platforms
Linux, MacOS, Magento, Heroku, Docker
Storage
MongoDB, Elasticsearch, PostgreSQL
Other
Cordova, Apollo, Search
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