Skip to main content

Open Source

Various open source software projects I created in recent years. As one can see there is a strong focus on Android (in the past) and Java cryptography/security themed libraries. Most of them can be found on GitHub and are published on Maven Central.


GitHub · · Java · 26 · v1.0.1
SLF4J binding for Timber - a logger with a small, extensible API which provides utility on top of Android`s normal Log class.


GitHub · · Java · 277 · v1.0.0
A shared preference implementation for confidential data in Android. Per default uses AES-GCM, BCrypt and HKDF as cryptographic primitives. Uses the concept of device fingerprinting combined with optional user provided passwords and strong password hashes.


GitHub · · Java · 149 · v1.6.1
Bytes is a utility library that makes it easy to create, parse, transform, validate and convert byte arrays in Java. It supports endianness as well as immutability and mutability, so the caller may decide to favor performance.


GitHub · · Java · 64 · v2.0.0
A standalone Java 7 implementation of HMAC-based key derivation function (HKDF) defined in RFC 5869 first described by Hugo Krawczyk. HKDF follows the “extract-then-expand” paradigm which is compatible to NIST 800-56C Rev. 1 two step KDF


GitHub · · Java · 13 · v1.7.0
A cryptographically secure pseudorandom number generator cli tool printing in a wide variety of byte encodings (hex, base64,..) and for many programming languages (c, java, c#, php, etc.) using NIST SP800-90Ar1 HMAC-DRBG. Supports external seeding from various true random services.


GitHub · · Java · 217 · v0.7.0
Under the Hood is a flexible and powerful Android debug view library. It uses a modular template system that can be easily extended to your needs, although coming with many useful elements built-in.


GitHub · · Java · 1810 · v1.3.0
A cli tool that helps signing and zip aligning single or multiple Android application packages (APKs) with either debug or provided release certificates. It supports v1, v2 and v3 Android signing scheme has an embedded debug keystore and auto verifies after signing.


GitHub · · Java · 34
A crash recovery library for Android. It allows tracking and handling crashes with different rules for debugging and production.


GitHub · · Java · 156 · v1.0.4
A tool that enables advanced features through adb installing and uninstalling apps like wildcards and multi device support. Useful if you want to clean your test device from all company apks or install a lot of apks in one go. Written in Java so it should run on your platform.


GitHub · · Java · 2
This is the prototype developed during the “Bankathon16” hackathon hosted by INSO. It was a 2 day event, 3 developer worked on the project. This project achieved 2nd place in the ranking.


GitHub · · Java · 51 · v1.2.0
A full-featured indoor positioning system that was developed during my master thesis. It has a javascript based rich UI and has a server-client architecture.


A multi platform image density converting tool converting single or batches of images to Android, iOS, Windows or CSS specific formats and density versions given the source scale factor or width/height in dp. It has a graphical and command line interface and supports many image types (svg, psd, 9-patch, etc.) aswell as some lossless compressors like pngcrush.

Snippet: Simple Sigma.js AngularJs Directive

Gist · · JavaScript · 4 Comments · 3 Files
Simple Sigma.js AngularJs Directive: Since I did not find any angularjs directive for angularjs I created a little simple of my own. This is by no means a ready-for-all solutions, but all the features I needed at the time; it is easily extended to your needs and maybe sometimes somebody will do a full-blown directive for sigma.js Tested: angularjs 1.2.25, sigma.js 1.0.3 (should work with angularjs 1.3).