Stian Herdal
CEO at HRDL
Greater Oslo Region Norway
Summary
👤
SeniorStian Herdal is a CEO and software engineer based in the Greater Oslo Region with eight years of hands-on experience building and improving cross-platform open-source applications. He combines product leadership at HRDL with deep technical contributions to projects like Xournal++ (performance and pen input rendering), KOReader (PDF rendering and device-specific UI) and Sioyek (advanced PDF search and UX improvements). His work spans backend, frontend, and low-level rendering optimizations, showing a strong comfort with C++/GTK, MuPDF and embedded/device concerns. Notably, he improves core user interactions—pressure-sensitive strokes, touch gestures and multi-line search handling—revealing attention to both performance and subtle UX details.
8 years of coding experience
English
Github Skills (30)
c-language10
pdf10
pdf-viewer10
lua10
gtk10
pdf-render10
cprogramming-language10
pdf-rendering10
sdl9
regex9
pen8
data-structures8
uid8
data-structure8
front-end-development8
Programming languages (13)
Github contributions (5)
ahrm/sioyek
Jun 2022 - Sep 2022
Sioyek is a PDF viewer with a focus on textbooks and research papers
Role in this project:
Full-stack Developer
Full-stack DeveloperContributions:13 commits in 3 months
Contributions summary:Stian primarily focused on enhancing the Sioyek PDF viewer's functionality. They implemented features such as configurable middle-click highlighting, case-insensitive and regex search capabilities, and the parsing of MuPDF 1.20 links. The user also addressed several bugs, including issues with ligatures and time differences, and improved the search functionality by treating multi-line matches as single entries. These changes indicate a focus on improving core functionality and user experience.
pdfpdf-viewerpopplerpdf-generationtextbooks
koreader/koreader
Mar 2022 - Apr 2022
An ebook reader application supporting PDF, DjVu, EPUB, FB2 and many more formats, running on Cervantes, Kindle, Kobo, PocketBook and Android devices
Role in this project:Full-stack Developer
Full-stack DeveloperContributions:5 reviews, 3 commits, 3 PRs in 1 month
Contributions summary:Stian contributed to multiple areas within the KOReader project, demonstrating a broad understanding of the application's codebase. They implemented features, addressed bugs, and improved performance, particularly focusing on PDF rendering, UI updates, and plugin functionality (Wallabag). Their work involved changes to both the frontend (UI, device-specific code) and backend (PDF document handling, plugin logic) aspects of the e-reader application. The user also demonstrates a basic understanding of SDL, demonstrating a low-level understanding of the application's interface.
ebookkobocbzpdf-reflowdjvu
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