Publication
Forex Algorithmic Trading: A Practical Tale for Engineers
https://www.toptal.com/data-science/algorithmic-trading-a-practical-tale-for-engineers
Rogelio is available for hire
Hire RogelioRogelio Nicolas Mengual
Verified Expert in Engineering
PHP Developer
Location
Jujuy, Argentina
Toptal Member Since
May 6, 2013
Rogelio is a versatile, positive, and self-motivated full-stack engineer with over 15 years of experience in various programming languages, frameworks, and platforms. Rogelio enjoys taking on new challenges and constantly strives to learn new skills.
Portfolio
Aqui LLC
PHP, MySQL, Laravel, Alpine.js, Canvas, HTML5 Canvas, JavaScript
Toptal, LLC
Laravel, PHP, Credit Scores, Credit Ratings, MySQL, NGINX, Software Design...
UNRIVAL
PHP, Vue, HTML, CSS, Amazon Web Services (AWS), Burp Suite, Penetration Testing...
Experience
Availability
Full-time
Preferred Environment
Git, Linux, PHP, Laravel, MySQL
The most amazing...
...thing I've done is build the entire infrastructure and develop all the systems that are part of one of the leading real estate platforms in America.
Work Experience
PHP Developer
2022 - 2023
Aqui LLC
- Created the relational database structure to support the business logic.
- Developed the application using Laravel 9, Alpine.js, and Tailwind for styling.
- Set up the server's infrastructure to support the expected demand.
Technologies: PHP, MySQL, Laravel, Alpine.js, Canvas, HTML5 Canvas, JavaScript
Senior Full-stack Engineer
2021 - 2022
Toptal, LLC
- Developed an application that takes in data from credit scoring sub-systems and makes decisions based on that input.
- Created infrastructure in the cloud and built up the architecture to a solution that can be scaled.
- Created tests for all scenarios to automate deployment.
Technologies: Laravel, PHP, Credit Scores, Credit Ratings, MySQL, NGINX, Software Design, Integration, Google Geocoding API, Payment APIs, Online Payments, Symfony, Docker, RabbitMQ, JavaScript
Full-stack Developer | Security Auditor
2020 - 2021
UNRIVAL
- Performed a security audit, finding and correcting security issues in the server infrastructure and the application layer.
- Developed new functionality in the web application and worked in PHP and Vue.
- Created a new way of deploying environments in AWS.
- Added a load balancer for the web application and configured the servers to work under a new architecture.
Technologies: PHP, Vue, HTML, CSS, Amazon Web Services (AWS), Burp Suite, Penetration Testing, Server Security, Web App Security, Linux Administration, Linux, MySQL, Apache2, LAMP, Git, Full-stack, System Security Developer, Relational Databases, Web Development, Application Security, Apache HTTP Server, VirtualBox, Vagrant, Software Architecture, Cybersecurity, NGINX, Architecture, Virtualization, Linux Server Administration, Security, Amazon EC2, REST, Software Design, Legacy Software, Legacy Code, Integration, API Integration, APIs, JavaScript
Senior Full-stack Web Developer | System Administrator
2019 - 2021
Percipient
- Created a new application that interacted with Salesforce.
- Developed a new Laravel application that exported MS Word documents based on a set of dynamic questions.
- Performed troubleshooting and enhancements of existing applications using different versions of Laravel.
- Created different development and testing environments and managed the security policies in AWS.
Technologies: Laravel, Linux, Amazon Web Services (AWS), MySQL, Apache2, NGINX, Vue, HTML, CSS, Salesforce, Salesforce API, System Administration, PHP, LAMP, Git, Full-stack, Relational Databases, Web Development, Apache HTTP Server, VirtualBox, Vagrant, Architecture, Linux Administration, Virtualization, Linux Server Administration, Amazon EC2, DocuSign, REST, Software Design, Integration, API Integration, APIs, Payment APIs, JavaScript
Back-end Developer
2017 - 2018
Giving Assistant
- Developed algorithms for better sorting of suggestions offered to potential clients.
- Created the API to connect with a strategic partner that offers peer-to-peer money raising.
- Improved existing back-end functionality, extending its capabilities and doing more reusable modules.
- Participated in architectural decisions for high-demand services.
Technologies: Amazon S3 (AWS S3), Algolia, MySQL, Linux, Yii 2, PHP, Apache2, LAMP, Git, Relational Databases, Web Development, Apache HTTP Server, VirtualBox, REST, Integration, API Integration, APIs, Payment APIs
Back-end Developer
2017 - 2018
Adverator (via Toptal)
- Created back-end admin panels for different types of media ads and managed printed media specs and images.
- Troubleshot and modified an uploading mechanism to interact with S3 buckets.
- Improved existing back-end modules to make the code more reusable.
Technologies: Vagrant, Linux, Apache, JavaScript, CodeIgniter, PHP, MySQL, Apache2, LAMP, Git, Full-stack, Relational Databases, Web Development, Apache HTTP Server, Amazon S3 (AWS S3), REST
Web Developer
2017 - 2017
Hiring Output (via Toptal)
- Added features to a local labor platform using PHP on the back end and JavaScript on the front end.
- Fixed bugs in JavaScript code that were not working as expected.
- Improved performance of the application by removing idle processes and functions.
- Created data importing processes from different sources.
Technologies: Heroku, MySQL, CSS3, HTML5, jQuery, CodeIgniter, PHP, Apache2, LAMP, Git, Full-stack, Relational Databases, Web Development, Apache HTTP Server, APIs, JavaScript
Director of Engineering
2015 - 2016
Toptal
- Helped the team improve the internal process to funnel the right talents to the clients.
- Created specifications for new features on the working platform.
- Interviewed clients, analyzed specs, and made decisions about prospect projects.
- Supervised the working relationship among developers and clients.
- Solved issues from billing to technical to ensure the quality of the provided service.
Technologies: Software Architecture
Technical Screening Team Leader
2014 - 2016
Toptal
- Helped improve the internal process for talent testing and selection.
- Trained new team members that wanted to start screening Toptal prospects.
- Led meetings and managed a team of experienced developers.
- Created new tests for the different technical roles.
- Coordinated with different teams to tackle different kinds of issues derived from screening.
Technologies: Algorithms
Technology Leader and Full-stack Developer
2013 - 2015
ProHatch (via Toptal)
- Rebuilt the payment process flow for a better user experience.
- Created a blog module for the administrator accounts.
- Implemented news publishing capabilities for administrators.
- Built all the front-end landing pages and templates.
- Fixed several broken modules and classes within the legacy code.
- Developed a cron job to monitor projects' phase status.
- Implemented an admin panel that allows admin users to control the platform processes.
- Created a chart generator for decision-making staff.
- Built the back-end and front-end for the new real estate business of the company.
- Performed SysAdmin tasks on the server (migrations, SSL installations, upgrades, backups, cron jobs to trigger and control processes, and other configurations).
Technologies: Linux Server Administration, Bash, Google API, Facebook API, Bootstrap, jQuery, JavaScript, CSS, HTML, CodeIgniter, PHP, System Administration, Linux, MySQL, Apache2, LAMP, Git, Relational Databases, Web Development, Apache HTTP Server, Redis Cache, Software Architecture, WePay, NGINX, Architecture, Linux Administration, Virtualization, Security, REST, Legacy Software, Legacy Code, Integration, API Integration, APIs
Freelance LAMP Developer and Support
2012 - 2014
InitSoft
- Customized a Drupal login and registration module to include an SMS authentication system that uses the Twilio API.
- Created bash seed scripts to automate installations of CMS apps into the virtual hosts (CMS: Drupal, WordPress, Joomla!, EzPublish, and many more).
- Modified a Perl script that handles records on DNS configuration files.
- Provided solutions to clients' broken CMS applications (Drupal, Joomla!, WordPress, OpenMicroBlog, EzPublish and many more).
- Fixed the DBMGR daemon start script for a customized Vagrant box that was used as a model to build a web server box model.
- Created online documentation for clients to reduce support time.
Technologies: Shell Scripting, Twilio API, Git, Perl, WordPress, Drupal, MySQL, PHP, Linux, Apache2, LAMP, Full-stack, Relational Databases, Bash, Web Development, Apache HTTP Server, Linux Administration, Linux Server Administration, Integration
PHP/Joomla Developer
2013 - 2013
LDS Trucking (via Toptal)
- Fixed broken Joomla modules.
- Fixed the Joomla layout.
- Updated the site content.
- Installed new modules.
- Customized new modules installed to fit the layout design.
- Fixed a front page slideshow and added jQuery effects.
Technologies: jQuery, Joomla, PHP, MySQL, Apache2, LAMP, Git, Full-stack, Relational Databases, Web Development, Apache HTTP Server
Senior Web Developer
2013 - 2013
JCCRANE (via Toptal)
- Created Twitter integration for the BuzzFactory website.
- Fixed a broken Scrollable.js script.
- Fixed broken Joomla modules.
- Updated broken CSS styles.
- Updated PHP code for broken Joomla modules.
Technologies: Joomla, CSS, jQuery, PHP, JavaScript, MySQL, Apache2, Git, Full-stack, Relational Databases, Web Development, Apache HTTP Server
System Admin/Drupal Engineer
2013 - 2013
Patients Pending, Ltd. (via Toptal)
- Migrated a Drupal 7 web application from source to destination server.
- Recreated cron jobs that ran on the source server.
- Created a full backup of the source server.
- Customized the permissions rules editing sudoers file.
- Created and configured chroot SFTP access accounts.
Technologies: Linux, Drupal 7, PHP, System Administration, MySQL, Apache2, LAMP, Git, Full-stack, Relational Databases, Web Development, Apache HTTP Server
AIX Developer
2010 - 2013
IBM
- Created a ksh shell script to add steps of a batch process that involved communication between AIX and mainframe servers.
- Modified a Java program that generated serial number records to include a new numeration structure.
- Modified a Java GUI application that interacts with the mainframe. Added new validations and created new input fields.
- Created a PL1 job that interacted with the DB2 existent database and created some tables after some processing.
- Modified a Perl web application (located in an AIX server) that was not working since many changes done in the mainframe servers.
- Created a ksh shell script that performed some processing and took and sent data from/to the mainframe servers, keeping a record of the process on DB2 tables to resume steps in case of failure.
- Modified the ksh shell script to include new record structure types.
- Modified the D-mate script (IBM's Perl based custom framework language), to add new logic for parts processing.
- Modified some PHP script that interacted with D-frame to change serial code calculations.
- Created a ksh shell script to separate Lenovo serials from IBM serials, write it to DB2, and send data to the mainframe for further processing.
- Provided on-call support, taking care of batch failures on the mainframe and AIX servers. This on-call was required one entire week per month.
Technologies: IBM Db2, PHP, Perl, Java, Shell Scripting, Linux, Git, Relational Databases, Bash, Web Development, Apache HTTP Server, Bash Script, Sed
Security Server Administration
2009 - 2010
Hewlett Packard
- Created a Unix shell script (ksh/bash/tcsh) that took care of massive creation of user accounts based on a user model.
- Created a Unix shell script (ksh/bash/tcsh) that took care of modifying user's permissions based on a model user.
- Created a Unix shell script (ksh/bash/tcsh) that resets passwords, disable, or deletes users listed on a file.
- Modified sudoer's file of many Unix-based servers. This was done depending on the client's security policy.
- Supported a PHP-based application for user ID control.
- Provided system administration and security support for more than 2000 Unix servers (AIX, Solaris, AS400, HP-UX, Red Hat) and 500 Windows servers.
- Collaborated with the disaster recovery on-call team, providing the SA and security support required for such events.
Technologies: PHP, KSH, Bash, Linux, Git, Web Development, Apache HTTP Server, Shell Scripting, Bash Script, Sed
IREG Technician
2006 - 2007
Claro
- Performed IR21 tests to ensure signaling between carriers.
- Performed AA14 tests to guarantee correct communication between the different operators worldwide.
- Monitored and troubleshot SS7 signaling between carriers, acting on the results to guarantee the correct communication.
- Performed roaming tests based on the GSM Association reference documents IR24, IR35 and IR32 (gsm, gprs and CAMEL service).
- Checked TADIG department charges against networking records and correct deviations to ensure correct billing.
Technologies: Bash
MCI-Verizon Nationwide Representative
2005 - 2006
Apex America
- Provided support for billing issues, ensuring client satisfaction.
- Supported technical issues doing a follow-up with the client until correct resolution.
- Changed existing plans and tested correct billing upon change completion.
- Created new client accounts.
- Managed and troubleshot Citrix environments.
Technologies: Citrix
Experience
Starin
http://starin.bizFull-stack development in PHP and JS for a wide variety of projects. I led tasks such as integrating APIs, writing custom modules, troubleshooting and solving issues, designing new DB structures, applying new design implementations, and more.
Frequenter
I was primarily in charge of migrating a mobile back-end system to a new server. I also oversaw counter-hacking measures to regain control from a ransomware that had infected the stack, as well as hardening the system to prevent future security breaches.
Giving Assistant
https://givingassistant.orgI worked primarily as a PHP back-end developer, in charge of integrating APIs, improvements, and new implementations for the company. Its primary business is allowing retail consumers to give to charity while they spend money online.
Business Trading Platform
I contributed as a full-stack developer for a company creating an MVP that connects the necessities of the average household and service providers like electricians, plumbing services, and other maintenance work.
Addy (formerly Adverator)
https://www.addy.co/I was in charge of the full-stack development for this advertisement company, which makes local ads easy and accessible. I worked on the implementation of new functionalities and improved the existing ones.
Tech Books for Kids
Tech Books for Kids is a personal project that aims to introduce children and young teens into the rational world of logic, computer science, programming, and math. I was in charge of the ideas, drawings, and coloring.
Leading Real Estate Platform
Full-stack development for a leading real estate platform. I handled coding for front- and back-end solutions, creating system designs (BD structures, networking, caching, etc), and managing infrastructure.
ProHatch
I worked as the technology lead and full-stack developer on a crowd-funding platform now in business with real estate deals. I handled the architecture, infrastructure, and full-stack implementation of the platform. It used WePay to process payments, and the framework used was CodeIgniter.
OGMobi
Developed an intelligent polling system from the scratch, to collect data and present resumed information useful to the marketing department and the decision makers.
WebEnabled
http://www.webenabled.comDeveloped and customized functionality for the site, developing seed scripts to install CMSs in web apps on virtual servers. Performed support for developers using the platform.
LDS Trucking
I was in charge of restoring the site's functionality and fixing the layout front- and back-end modules broken after a Joomla! update.
Buzz Factory
http://buzzfactory.bizI was in charge of fixing a broken Joomla! site after a migration and upgrade. I fixed several front-end and back-end modules, and also added a Twitter module and scrollable.js.
Timesulin
http://timesulin.com/Performed several DevOps tasks required on a migration and configuration for the online platform.
Illustration
I enjoy creating illustrations on my free time (which is not much). Here's a doodle made in 40 minutes.
Personal Page
http://nicomengual.comMy personal page. It's a simple point of contact and web presence.
Skills
Languages
Bash, PHP, SQL, CSS, HTML, JavaScript, Sed, Bash Script, KSH, Java, HTML5, CSS3, Python, Perl, Octave
Frameworks
Bootstrap, CodeIgniter, Laravel, Yii 2, Symfony
Libraries/APIs
jQuery, Stripe, Google Maps, Twilio API, Google API, Salesforce API, Google Geocoding API, Facebook API, Vue, Pandas, NumPy, Scikit-learn, HTML5 Canvas
Tools
Apache HTTP Server, NGINX, Vim Text Editor, Apache, Git, Vagrant, VirtualBox, MATLAB, RabbitMQ, Canvas
Paradigms
Model View Controller (MVC), Functional Programming, Object-oriented Programming (OOP), REST, Penetration Testing, Data Science, DevOps, Database Design
Platforms
Apache2, LAMP, Linux, Twilio, Amazon Web Services (AWS), Amazon EC2, Heroku, Drupal, WordPress, Drupal 7, Joomla, Burp Suite, Salesforce, Algolia, Docker
Storage
MariaDB, Relational Databases, MySQL, Memcached, Elasticsearch, Amazon S3 (AWS S3), Redis, Redis Cache, IBM Db2, SQL Architecture
Industry Expertise
Cybersecurity, High-frequency Trading (HFT), Security
Other
System Administration, Ajax, Full-stack, Algorithms, Information Security Management Systems (ISMS), System Security Developer, Web Development, Software Design, Legacy Software, Legacy Code, API Integration, APIs, RETS, Web Scraping, WePay, Perfex CRM, Server Security, Software Architecture, DocuSign, Architecture, Application Security, Integration, Alpine.js, Payment APIs, Online Payments, OpenAI GPT-3 API, OpenAI GPT-4 API, Shell Scripting, Linux Server Administration, Front-end, Back-end, Web App Security, Linux Administration, Virtualization, Machine Learning, Credit Scores, Credit Ratings, Technical Leadership, OpenAI API, Programming, Simulations, Data, IT Systems Architecture, Computer Science, Statistics, Algebra, Linear Algebra, Matrix Algebra, Operating Systems, Relational Database Design, Networking, Cisco Networking, Optimization
Education
2007 - 2011
Bachelor's Degree in Computer Science
National Technological University - Cordoba, Argentina