N.V Rosvall's homepage

Niko Rosvall

Updated: 2023-09-18

This is not much of a webpage when it comes to the design. I'm not a web designer, and I prefer web pages that are fast and simple. Just like I prefer software. However, these pages should work OK on your preferred tracking device too.

For my blog, see my weblog.

The easiest way to contact me is by email: niko@byteptr.com. Feel free to follow me on Mastodon. Or /msg me on IRC (sarthalion@liberachat).


I've written a lot of software during the years, but here are the ones I care about the most. These are in active development.


Bren is a program for renaming multiple files at once. Bren is versatile and offers support for post-rename scripting with GNU Guile. Bren runs on the command line. It's fast, it's written in C and licensed under the GPL.

Bren has its own website in here.


Memo is a Unix-style note-taking software for POSIX compatible systems. At the moment it's tested on GNU/Linux and on FreeBSD, but it should be portable to other platforms. Memo also works on Cygwin and WSL. Memo runs in the Unix heartland, the shell.

Memo has its own website in here.


SECRET is a cross platform, command line, file encryption program. It allows secure file and directory encryption from the command line. SECRET also includes SecretEngine.dll library which is an easy to use file encryption library for .NET.

SECRET is licensed under the MIT open source license. Source code is available on Github.

Download version 1.6 precompiled binary for Windows or for Linux and see SECRET manual (pdf) for usage. It also explains technical details about the encryption algorithms in SECRET.

SECRET is also available from FOSSHUB.

Both binaries for Windows and for Linux are standalone builds they do not need .NET to run.

Software not maintained anymore

If you would like to take over any of these projects, feel free to contact me, I'm happy to help.


Ylva is a command line password manager. Ylva is written in C and is licensed under the MIT license. Ylva is mostly developed on Linux, but should work on BSD too.



Wilhelmina is a password manager. It's an open source (licensed under GPLv3+) software. Source code is available on Github. It's written for Windows, but should be fairly portable to other operating systems.

Wilhelmina has its own website in here.

Ancient things

Back in 2006 I was designing LTSP (Linux Terminal Server Project) for a classroom in Finland. Here's the design documentation (PDF, in Finnish).

I also created my own Linux Live-CD, back when they were not that common. See the documentation (PDF, in Finnish).

Copyright © 2023 Niko Rosvall