Krasimir is available for hire

Krasimir Hristozov

Verified Expert in Engineering

Software Developer

Location

Ruse, Bulgaria

Toptal Member Since

February 25, 2017

Krasimir has been programming and leading software development teams for 15 years—mainly using PHP and all sorts of custom-built and off-the-shelf frameworks. He has experience with startups and small teams and can comfortably fill multiple roles (web developer, product manager, project manager, system analyst, and business analyst). He is a big proponent of clean coding and following best software development practices.

Back-end Development SQL MySQL PHP LAMP Project Management Unit Testing Agile Software Development PostgreSQL JSON Laravel Stripe API Stripe Software as a Service (SaaS)Back-end Architecture Model View Controller (MVC)

Portfolio

Aikidesk Ltd

Pusher, Amazon Simple Queue Service (SQS), Amazon Simple Email Service (SES)...

Intermedia Ltd

jQuery, PostgreSQL, MySQL, Symfony, Laravel, PHP, Project Management, React...

Freelancer

PostgreSQL, MySQL, WordPress, Symfony, Laravel, PHP, APIs, Back-end Development...

Experience

Object-oriented Programming (OOP) - 20 years PHP - 20 years Project Management - 15 years Systems Analysis - 10 years Amazon Web Services (AWS) - 10 years Agile Software Development - 10 years Software as a Service (SaaS) - 10 years Laravel - 6 years

Availability

Part-time

Preferred Environment

Git, Sublime Text, Linux CentOS 7, Back-end Architecture, JavaScript

The most amazing...

...project I've worked on was a social network for sports fans.

Work Experience

Product Manager

2015 - PRESENT

Aikidesk Ltd

Gathered user requirements and feedback, preparing a backlog of suggested improvements.
Aligned the backlog with the business objectives of the company.
Prepared, prioritized, and budgeted the requirements for the next sprint.
Communicated the requirements to the development team.
Oversaw the work progress, identifying and removing obstacles.

Technologies: Pusher, Amazon Simple Queue Service (SQS), Amazon Simple Email Service (SES), Backbone.js, MySQL, Laravel, PHP, Project Management, React, JavaScript, Amazon Web Services (AWS), LAMP, Agile Software Development, Software as a Service (SaaS), Amazon Linux, Object-oriented Programming (OOP), API Integration, RESTful Development

Project Manager

2003 - PRESENT

Intermedia Ltd

Performed system analysis and business analysis of the customer requirements.
Wrote proposals with technical and functional specifications.
Established development guidelines and QA procedures.
Created development schedules and supervised the developers.
Performed code reviews, pair programming sessions, and quality assurance with the developers.
Worked on programming, testing, and system administration (DevOps) on CentOS 6/7, Ubuntu 14, and Amazon Linux servers.

Technologies: jQuery, PostgreSQL, MySQL, Symfony, Laravel, PHP, Project Management, React, Back-end Architecture, JavaScript, Amazon Web Services (AWS), LAMP, Agile Software Development, Stripe API, Stripe, Algorithms, Amazon S3 (AWS S3), Scrum, Amazon Linux, PHPUnit, Refactoring, Systems Analysis, Object-oriented Programming (OOP), Clean Code, Dependency Injection, Unit Testing, SQL, JSON, Statistics, Negotiation, Design Patterns, Automated Testing, Stripe Payments, Stripe Subscriptions, API Integration, RESTful Development, REST, Model View Controller (MVC), Software Architecture, Data Structures, Product Management, Business Analysis, SOLID Principles

Web Developer | Project Manager Product Manager

2000 - PRESENT

Freelancer

Worked on over 100 web development projects. Some highlights are listed below.
Built single-handedly the whole CRM/CMS back-end of a system for a large international organization. The back-end is currently used to manage over 50 dynamic websites for different countries, in more than 20 languages.
Led the development of a social network for sports fans with over 300,000 registered users at its peak.
Led the development of a HIPAA-compliant system to manage the phone communication between physicians and patients. The system is in use in over 100 medical practices in the US.
Developed a system targeted at clinic owners in the UK for self certification for the Disability Discrimination Act 1995.

Technologies: PostgreSQL, MySQL, WordPress, Symfony, Laravel, PHP, APIs, Back-end Development, Vue, React, Back-end Architecture, JavaScript, Amazon Web Services (AWS), LAMP, Agile Software Development, Algorithms, Amazon S3 (AWS S3), Scrum, Amazon Linux, PHPUnit, Refactoring, Systems Analysis, Object-oriented Programming (OOP), Clean Code, Dependency Injection, Unit Testing, SQL, JSON, Codeception, Statistics, Negotiation, Design Patterns, Automated Testing, Stripe Payments, Stripe Subscriptions, API Integration, RESTful Development, REST, Model View Controller (MVC), Software Architecture, Data Structures, Product Management, Business Analysis, SOLID Principles

Seasoned PHP Engineer

2019 - 2020

NBL Media, LLC

Led an upgrade of the ten-year-old legacy back-end system from CakePHP 2.0 on PHP 5.3 to CakePHP 2.10 on PHP 7.4.
Performed multiple database and code optimizations to eliminate bottlenecks and improve the user experience of the Web dashboard and mobile apps.
Improved the security of the back-end API by eliminating existing vectors of attack (e.g., through SQL injection/XSS) and improving the user authentication and authorization process.

Technologies: PHP, MySQL, Linux, CakePHP, Algorithms, Amazon S3 (AWS S3), Scrum, Amazon Linux, Refactoring, Systems Analysis, Object-oriented Programming (OOP), Clean Code, Dependency Injection, Unit Testing, SQL, JSON, Negotiation, Design Patterns, Automated Testing, API Integration, RESTful Development, REST, Model View Controller (MVC), Software Architecture, Data Structures, Product Management, Business Analysis, SOLID Principles

Experience

Aikidesk

https://www.aikidesk.com/

A customer support system in the cloud. It is used by one of the largest web-hosting companies in Central and Eastern Europe, serving over 100000 customers. It's written in Laravel and MySQL and deployed to AWS.

Landlord Vision

https://www.landlordvision.co.uk/

Online property management and accounting software for landlords in the UK. It's been on the market for ten years and has been used by 20 thousand landlords. The software is built in Laravel/React and deployed to AWS.

Technical Writing

https://developer.okta.com/blog/authors/krasimir-hristozov/

I wrote about 20 articles for Okta on web application security/authorization and authentication/JWT/OAuth2 topics. Some of them are still popular resources used as reference material by other developers.

Skills

Languages

SQL, PHP, JavaScript

Frameworks

Laravel, PHPUnit, Symfony, Codeception, JSON Web Tokens (JWT), OAuth 2, CakePHP

Libraries/APIs

Stripe API, Stripe, Apiary API, REST APIs, React, jQuery, Backbone.js, Pusher, Vue

Tools

Amazon Simple Queue Service (SQS), Git, Sublime Text, Amazon Simple Email Service (SES)

Paradigms

Clean Code, Unit Testing, Refactoring, Dependency Injection, RESTful Development, Scrum, REST, Model View Controller (MVC), Agile Software Development, Object-oriented Programming (OOP), Automated Testing, Design Patterns, Back-end Architecture

Platforms

Amazon Linux, LAMP, Linux, Amazon Web Services (AWS), Linux CentOS 7, WordPress

Storage

Amazon S3 (AWS S3), JSON, PostgreSQL, MySQL

Industry Expertise

Project Management

Other

Stripe Payments, Stripe Subscriptions, API Integration, APIs, Systems Analysis, Back-end Development, Software Architecture, Software as a Service (SaaS), Algorithms, SOLID Principles, Data Structures, Product Management, Business Analysis, Information Technology, Negotiation, Statistics, Writing & Editing, Okta, Web Security, User Authentication

Education

1996 - 2002

Master's Degree in Information Technology

University of Ruse - Ruse, Bulgaria

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring