Jonatã Bolzan Loss
Software EngineerExperience
Dec 2019present
Professional Freelancer
Upwork Remote- Top Rated on Upwork with 100% Job Success Score; active on the platform since December 2019
- Full-stack web and desktop software engineering for international clients — Python, Flask, PySide6/PyQt, Bootstrap, Grav/Twig front-ends, PostgreSQL
- Portuguese ↔ English technical translation: product documentation, training materials and software localization; subtitle and voiceover pipelines
- Ship and maintain open-source products across the stack, including Subtitld (subtitle editor), nafi·la (queue SaaS), dubd.me (auto-dubbing SaaS) and the Inkscape Output Pro plugin
- Audio-engineering consulting using Pro Tools, Audacity and FFmpeg pipelines for specialized recording and post-production workflows
Dec 2012Nov 2019
Audio Engineer · Software Support Engineer · IT Support Specialist
Watchtower Bible and Tract Society — Brazil branch Cesário Lange, SP, Brazil- IT Support Specialist (Dec 2012–Nov 2016): cross-team IT infrastructure and media support for the Brazil branch; troubleshooting, imaging, scripting and internal tool maintenance
- Software Support Engineer (Jul 2016–Nov 2019): designed and built multiplatform desktop applications (Python/Qt, C++) to automate audio and video production workflows; collaborated directly with the upstream Audacity team to produce a custom video-enabled build used daily by hundreds of in-house technicians
- Audio Engineer (Dec 2016–Nov 2019): audio recording, mixing, post-production and signal-chain work for in-house productions; Pro Tools and Audacity pipelines, mic/gain-staging, mastering
Jan 2011Nov 2012
Freelance Graphic Designer
Australian Fitness Supplies Australia — remote- Packaging, product and marketing artwork for a fitness-equipment retailer over nearly two years
- Print-ready assets in Inkscape and GIMP; direct coordination with Australian printers and CMYK proofing
Jan 2009Jan 2012
Freelance Graphic Designer
99designs Remote- 200+ logo and brand-identity designs submitted over three years on the 99designs marketplace
- Participated in hundreds of design contests and invitational projects; built a reputation for clean, type-focused vector identity work
Jun 2005Feb 2011
Graphic Designer
Universal – Gráfica e Comunicação Visual Tapejara, RS, Brazil- Monthly layout of Revista Comunicação; print-ready packaging, publications, visual identity, banner and signage design
- Toolchain: Inkscape (vector), Scribus (DTP), GIMP (raster); full CMYK print-pipeline control and press-ready output
- Authored an exclusive Inkscape plugin for CMYK JPG/PDF export — later open-sourced as Inkscape Output Pro
Education
Feb 2026present
Bachelor of Engineering — Computer Software Engineering
Centro Universitário União das Américas (Uniamérica Descomplica) Remote, Brazil
20192020
Professional Certificate in Computer Science (CS50)
Harvard University Online
20062009
English Linguistics — Basic, Intermediate & Advanced
CCAA Brazil
20022004
High School Diploma
Escola Estadual de Ensino Médio Senhor dos Caminhos BrazilSelected Projects
2020present
Subtitld Flagship
Open-source subtitle editor- Multiplatform desktop application for creating, transcribing and editing subtitles — SRT, SSA, TTML, SBV, DFXP, VTT, XML, SCC and SAMI formats
- Built with Python and PySide6; uses FFmpeg for media handling and OpenCV for frame-accurate waveform and scene detection
- Packaged for Linux, macOS and Windows; active user community with public issue tracker and contributions from outside developers
2025present
nafi·la
Real-time queue-management SaaS- Virtual ticketing system for businesses to organize customer service and broadcast live wait-line status on public display monitors
- Stack: Python, Flask, WebSocket, Bootstrap front-end, PostgreSQL; multi-device synchronization
2022present
dubd.me
Automatic video dubbing SaaS- Web service that transcribes, translates and re-voices videos using CoquiTTS; end-to-end speech pipeline with per-speaker voice selection
- Stack: Python, Flask, speech-to-text and speech-synthesis pipelines, FFmpeg media processing
2020present
picd.in
Image-sharing service with desktop capture app- Online image-sharing platform with companion Windows/Linux screenshot application; capture, upload and share in one workflow
- Web: Python/Flask; desktop client: Python/PyQt
2020present
abre.la & miud.in
URL shorteners (rtland.team)- Two production URL-shortening services built on Python/Flask with PostgreSQL storage and a Bootstrap front-end
2023present
barcode.monster
Free, community-driven barcode database- Open public barcode lookup and contribution service; Python/Flask with a JSON API and a PostgreSQL backend
2024present
os.watch
Operating-system directory- Curated directory of operating systems with metadata and comparisons; Python/Flask web app
Livre e Aberto & LinuxAvante
Portuguese-language Linux & open-source blogs- Two long-running blogs covering Linux, free software and open-source tooling; built on Grav CMS with custom Twig themes
bomdia.space
Inspirational image generator- Generates shareable daily “good morning” visuals with Portuguese inspirational messages for social media
20152019
Custom Audacity with video playback
In-house fork- Custom Audacity build with synchronized video playback for audio-post-production workflows; C++/Python, developed with the upstream Audacity team and deployed to hundreds of in-house technicians
Open Karaoke Producer
UltraStar · Performous lyric editor- Desktop tool for creating and timing UltraStar/Performous lyric files — Python/Qt
RTCam
Custom camera-control application- Bespoke camera-control software for the RT Vision platform; Python/Qt desktop UI with hardware integration
idLoc
Audio conversion & upload tool- Desktop application for batch audio conversion and file uploads — Python/Qt with FFmpeg integration
Kihvim, Presentd & Prat
Kingdom Hall media toolkit- Python/Qt desktop suite: Kihvim (video mixer), Presentd (secondary-screen media playback) and Prat (announcement creator) — tools for live media support
Pirate’s Battle & Gold Nut Race
Raspberry Pi games- Two PyGame titles designed for Raspberry Pi–based arcade/device form factors
Kaso & Projects
POS & workflow manager (PoC)- Proof-of-concept point-of-sale software (Kaso) and a desktop workflow manager (Projects); Python/Qt
2015present
Inkscape Output Pro
Inkscape extension- Inkscape plugin that exports CMYK JPG/PDF directly from SVG — fills a long-standing gap for print production workflows
- Most-starred repository on my GitHub (40+ stars); Python
20142020
Open DVD Producer
DVD authoring desktop app (archived)- Cross-platform DVD-authoring application with interactive menu editor — Python/Qt; source later moved to GitLab
Certifications
Aug 2019
AVID Certified Developer — Toolkit AAX
Avid Technology
Developer-level certification for building AAX audio plugins for the Pro Tools platform.
Dec 2009
Oral and Written Communication in English
CCAA
Complete track: Getting Started (Basic), On The Move (Intermediate), To The Top (Advanced).
Oct 2004
Basic Electronics — Radio, B&W and Color TV
Instituto Universal Brasileiro
Technical certification in fundamental electronics, radio-technician skills and analog television repair.
2026
Coursework — Centro Universitário União das Américas (Uniamérica Descomplica)
- Programming Basics (Apr 2026)
- Introduction to Web Development (Feb 2026)
- Scrum & Agile Methodologies (Mar 2026)
- Techniques & Tools for Projects (Mar 2026)
- AI Tools and Applications (Feb 2026)
- Productivity & Organization (Mar 2026)
- Basic Excel (Feb 2026)