Gabriel Efraín Torrejón Sejas
Available to hire
I am a results-driven systems engineer and developer with over 3 years of experience in full-stack development, specializing in building and modernizing web and mobile solutions. I am proficient in React, PHP, Python, and a range of modern technologies. I excel at delivering robust, user-centric applications that improve efficiency and business value.
In recent projects at DvSoft and Cosett, I have architected modules, implemented REST endpoints, migrated front-end to React, and delivered end-to-end solutions including an electronic invoicing system. I enjoy collaborating with teams to optimize workflows and bring digital ideas to life.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Language
Spanish; Castilian
Fluent
English
Advanced
Work Experience
FullStack Developer at DvSoft
June 1, 2022 - PresentRemote consultant and developer responsible for architecting and implementing modules for PMC Analytics (Deal Summaries, Deal Center, Hedge Accounting) and an Electronic Invoicing System for Cosett; built Python/Django REST APIs, migrated frontend to React v18 with TypeScript, developed C#/NET 8 REST APIs for SIN-based invoicing, and implemented end-to-end validation and error handling; contributed to multiple system developments for the Architects' College, Agronomy College, and the University Teachers Confederation (CUD), using Node.js/React.js; collaborated to streamline workflows and improve performance.
FullStack Developer at DvSoft
June 1, 2022 - PresentFor PMC Analytics, architected and implemented three major modules (Deal Summaries, Deal Center, Hedge Accounting) to significantly improve analytical capabilities. Developed and maintained REST APIs using Python and Django to support new functionalities and data flows, especially for the Hedge Accounting page. Contributed to front-end modernization by migrating key pages to React v18 with TypeScript, improving performance. Debugged production bugs in Python services to ensure system stability and provided backend support by adding REST endpoints for evolving business needs.
FullStack Developer at DvSoft
August 1, 2022 - PresentElectronic Invoicing System for Cosett: built a full-stack solution to record sales and generate legally compliant e-invoices for Bolivia’s SIN. Implemented a responsive Angular front end with PrimeNG and designed C#/.NET 8 REST APIs against PostgreSQL to manage sales records, tax calculations, and SIN submissions, with end-to-end validation and real-time invoice issuance.
FullStack Developer at DvSoft
August 31, 2023 - September 9, 2025Pegadhex Quotation Mobile App: architected and delivered a cross-platform React Native app with offline-first synchronization, enabling field crews to create and share quotes without network access. Modeled data in MongoDB with offline-first sync, streamlined quoting workflow by 30% through reusable UI components, and integrated in-app PDF export and email sharing for immediate client delivery.
FullStack Developer at Architects’ College (System Development)
January 31, 2025 - September 9, 2025Developed a full-stack web system using Node.js and React.js to manage key organizational functions, including user and client management, authentication, and a project/event management module to streamline administration and improve operational efficiency.
FullStack Developer at Agronomy College Tarija (System Development)
January 31, 2025 - September 9, 2025Built a Node.js/React.js web system for Tarija’s Agronomy College to manage administrative tasks, user management, membership tracking, and events/workshops with registration and attendance tracking.
FullStack Developer at CUD (Universidad Teachers Confederation) (System Development)
July 31, 2024 - September 9, 2025Developed a web system using Node.js and React.js to manage organizational functions for CUD, including registration, authentication, client management, and event/competition scheduling.
FullStack Developer at Federación Universitaria de Docentes (FUD) Tarija (System Development)
May 31, 2022 - September 9, 2025Created a comprehensive registration system for FUD Tarija, with admin interfaces for athlete/profile management and a real-time news section to communicate with organizers and participants.
Technical Support at Plurinational Electoral Body (OEP) - Transmission Operator
October 1, 2019 - September 9, 2025Provided technical support for the transmission of preliminary electoral results in District 1 of Tarija during elections.
Information Point at Plurinational Electoral Body (OEP)
December 1, 2017 - September 9, 2025On-site information point support during election processes in Tarija.
Technical Support at Santa Cecilia Educational Unit
June 30, 2018 - September 9, 2025Provided technical support and maintenance for Quipus computers; supported IT activities during the 1st Semester 2018.
FullStack Developer at DvSoft
June 1, 2022 - PresentArchitected and implemented three major modules for PMC Analytics (Deal Summaries, Deal Center, Hedge Accounting), significantly improving the platform’s analytical capabilities. Developed and maintained REST APIs using Python and Django; supported data flows for Hedge Accounting. Part of the migration and front-end modernization to React v18 with TypeScript; rebuilt key pages to enhance performance. Debugged and resolved production bugs in Python services and provided backend endpoints to meet evolving business needs.
FullStack Developer at Cosett
August 1, 2022 - PresentDeveloped a full-stack solution to record sales and generate legally compliant e-invoices for Bolivia’s SIN. Built a responsive Angular frontend with PrimeNG; designed and implemented C#/.NET 8 REST APIs against PostgreSQL to handle sales records, calculate tax, and submit electronic invoices via SIN; ensured end-to-end validation and error handling; provided ongoing technical support.
FullStack Developer at Pegadhex
August 31, 2023 - September 9, 2025Architected and delivered a cross-platform React Native app with offline-first synchronization, enabling field crews to create quotes and share them without internet. Modeled data in MongoDB with offline-first syncing; streamlined the quoting workflow by 30% through reusable UI components and in-app PDF export and email sharing.
FullStack Developer at Architects' College
January 31, 2025 - September 9, 2025Developed a full-stack web system to manage organizational functions for the Architects’ College, including modules for user and client management (registration, authentication, profile administration) and a project/event management system to improve administrative efficiency.
FullStack Developer at Tarija Agronomist Engineers College
January 31, 2025 - September 9, 2025Built a Node.js/React.js web system for Tarija's Agronomist Engineers College to manage administration, user management, membership tracking, events, and workshops with registration and attendance tracking.
FullStack Developer at University Teachers Confederation (CUD), Tarija
July 31, 2024 - September 9, 2025Developed a web system using Node.js, React.js, and Bootstrap to manage the University Teachers Sports Games of Bolivia; created a platform for event registration, scheduling, and results publication, improving communication for participants and organizers; designed an intuitive UI to enhance user experience.
FullStack Developer at Federación Universitaria de Docentes (FUD), Tarija
May 31, 2022 - September 9, 2025Designed and implemented a comprehensive registration system for the National Teachers Olympics; developed intuitive admin interfaces for athlete profiles and event details, and a dynamic news section for real-time updates.
Technical Logistic Support at SERECI, Tarija
December 1, 2020 - PresentMaintenance of technological equipment during elections for Departmental, Regional, and Municipal authorities 2021.
Transmission Operator at Plurinational Electoral Body (OEP), Tarija
October 31, 2019 - September 9, 2025Transmission of preliminary electoral results in Tarija District 1.
Technical Support at Santa Cecilia Educational Unit
June 30, 2018 - September 9, 2025Help with unlocking and activation of Quipus computers.
Information Point Associate at Plurinational Electoral Body (OEP)
December 31, 2017 - September 9, 2025Assistance in the election process for High Authorities.
Consultant and Developer at DvSoft
June 1, 2022 - PresentFull Stack Developer responsible for architecture and implementation of modules for PMC Analytics; developed REST APIs with Python/Django; migrated frontend to React v18 with TypeScript; debugged production issues; provided backend support and additional REST endpoints.
FullStack Developer at Cosett
August 1, 2022 - PresentElectronic Invoicing System for Bolivia’s SIN; built a full-stack solution with Angular front end (PrimeNG) and C#/.NET 8 REST APIs against PostgreSQL for sales records, tax calculations, and SIN web service submission.
FullStack Developer at Pegadhex Quotation Mobile App
August 1, 2023 - September 9, 2025Cross-platform React Native app with offline-first synchronization; modeled data in MongoDB; reusable UI components and in-app PDF export and email sharing to accelerate quotes to clients.
FullStack Developer at Architects’ College System Development
January 1, 2025 - September 9, 2025Developed a full-stack web system with Node.js and React.js for management of users, clients, projects, events; implemented authentication and profile administration; improved operational efficiency.
FullStack Developer at Agronomy College System Development
January 1, 2025 - September 9, 2025Web system with Node.js and React.js for Tarija branch; user management, membership tracking, events, and workshops (registration, attendance, information dissemination).
FullStack Developer at CUD (University Teachers Confederation) System Development
July 1, 2024 - September 9, 2025Web system using Node.js, React.js, and Bootstrap to manage university sports games: event registration, scheduling and results publication; user-friendly interface for attendees.
FullStack Developer at National Teachers Olympics System Development
May 1, 2022 - September 9, 2025Registration system for the Federación Universitaria de Docentes (FUD) Tarija; administration interfaces for athlete profiles, events, and a real-time news section for updates.
Technical Logistic Support at Civil Registry Department (SERECI), Tarija
December 1, 2020 - PresentMaintenance of technological equipment during elections for departmental, regional, and municipal authorities (2011-2021).
Transmission Operator at Plurinational Electoral Body (OEP)
October 1, 2019 - PresentTransmission of preliminary electoral results in Tarija, District 1.
Technical Support at Santa Cecilia Educational Unit
June 30, 2018 - September 9, 2025Help with unlocking and activation of Quipus computers (1st semester of 2018).
Information Point at Plurinational Electoral Body (OEP)
December 1, 2017 - PresentAssistance in the election process for high authorities of the Judicial Branch and the Plurinational Constitutional Tribunal.
Education
Bachelor in Humanities at La Salle School, Tarija
January 11, 2030 - December 1, 2012National Provision Title in Systems Engineering at UCB Regional Tarija
January 11, 2030 - December 1, 2021Systems Engineering at Catholic University of Bolivia “San Pablo” (UCB) Tarija
January 11, 2030 - December 1, 2021Bachelor in Humanities at La Salle School
January 11, 2030 - December 1, 2012Bachelor in Humanities at La Salle School, Tarija
January 11, 2030 - December 1, 2012Title in Systems Engineering (National Provision) at Catholic University of Bolivia “San Pablo” (UCB), Tarija
January 11, 2030 - December 1, 2021Bachelor in Humanities at La Salle School, Tarija, Bolivia
January 11, 2030 - December 1, 2012National Provision Title in Systems Engineering at UCB Regional Tarija
January 11, 2030 - December 1, 2021Systems Engineering (Graduation project, final defense score 95) at Catholic University of Bolivia 'San Pablo' (UCB)
January 11, 2030 - December 1, 2021Qualifications
Python University – Zero to Expert (Udemy)
January 11, 2030 - April 17, 2025React - The Complete Guide 2025 (incl. Next.js, Redux)
January 11, 2030 - January 16, 2025ANGULAR and ASP.NET Core REST API - Real World Application
January 11, 2030 - June 5, 2025Introduction to the Internet of Everything, Cisco Networking Academy
January 11, 2030 - April 1, 2018Outstanding participation in the National Robotics Contest – WRO 2012
January 11, 2030 - October 1, 2012Diploma: Second place in the Senior category of the III Robotics Olympics – WRO 2012
January 11, 2030 - August 1, 2012Diploma: Outstanding participation in the Senior High School category of the III Robotics Olympics – WRO 2012
January 11, 2030 - January 1, 2012National Provision Title in Systems Engineering
January 11, 2030 - December 1, 2021Systems Engineering graduation (final defense grade 95)
August 7, 2017 - December 1, 2021Python: Zero to Expert
April 17, 2025 - September 9, 2025React - The Complete Guide 2025 (incl. Next.js, Redux)
January 16, 2025 - September 9, 2025ANGULAR and ASP.NET Core REST API - Real World Application
June 5, 2025 - September 9, 2025Introduction to the Internet of Everything
April 1, 2018 - September 9, 2025Outstanding participation in the National Robotics Contest – WRO 2012
October 1, 2012 - September 9, 2025Second place in the Senior category of the III Robotics Olympics – WRO 2012
August 1, 2012 - September 9, 2025Outstanding participation in the Senior High School category of the III Robotics Olympics – WRO 2012
August 1, 2012 - September 9, 2025Python University – Zero to Expert (Udemy)
April 17, 2025 - September 9, 2025React - The Complete Guide 2025 (incl. Next.js, Redux) (Udemy)
January 16, 2025 - September 9, 2025ANGULAR and ASP.NET Core REST API - Real World Application (Udemy)
June 5, 2025 - September 9, 2025Introduction to the Internet of Everything (Cisco Networking Academy)
April 1, 2018 - September 9, 2025Outstanding participation in National Robotics Contest – WRO 2012 (Tarija, Cochabamba)
October 1, 2012 - September 9, 2025Second place in the Senior category of the III Robotics Olympics – WRO 2012 (Tarija)
August 1, 2012 - September 9, 2025Outstanding participation in Senior High School – WRO 2012 (Tarija)
August 1, 2012 - September 9, 2025Industry Experience
Software & Internet, Education, Government, Professional Services, Media & Entertainment, Other
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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