RSJ Software GmbH

Innovative products – software that simply works.

RSJ builds modern software products with their own websites — from label printing and 3D packing optimization to Python compilation, blockchain timestamps and portfolio allocation. Your entry point to off-the-shelf solutions and tailored development.

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LPS NG · Label Studio

Sample product 500 g

Shelf label · 60 × 40 mm

€ 2.49

4 012345 678900

Labels with host-supplied and static data — barcode included.

Py2Native · Build

app.py

cli.py

Python sources

app

native

Native binary

Compiles Python into native executables — no Python on the target machine.

Products

Own products, deployed worldwide

Several projects have grown into standard products that live on their own product websites — linked from this page as the umbrella.

lpsng.rsj.de

Next Generation Label Printing System

LPS NG

Label printing — easy, modern, anywhere

Creates and prints labels with host-supplied and static data right in your browser — from layout design in the Label Studio to print jobs, in the cloud or in your own data center.

Web-based Label Studio — no client installation required
Unicode & TrueType, EAN, QR, GS1 and DataMatrix
Cloud or on-premises, incl. Electronic Shelf Labels (ESL)

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3dpacker.rsj.de

Packing optimization

RSJ 3D Packer

Optimal packing solutions in 3D

A fast web application to determine optimized packing solutions for variable-sized items in variable-sized containers.

Heuristic optimization within seconds
Multiple container sizes, optional vertical rotation
Interactive 3D display — boxes, pallets, containers & trucks

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pdfmerge.rsj.de

PDF utility

RSJ PDF Merge, Sort & Split

Merge, sort and split PDFs

Combines, sorts and splits PDF documents — as a straightforward online service, with no local installation.

Fast batch processing of large documents
Flexible sorting and splitting
Runs directly in your browser

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py2native.dev

The Python Compiler

Py2Native

Python, compiled to native code

Compiles Python through C into native executables — no Python required on the target machine, with built-in cryptographically protected license management.

Your code is fully compiled to native machine code
Every executable bundles its own Python runtime
Windows, Linux & macOS — ideal for CI/CD and Docker

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timestampgit.dev

Cryptographic timestamps

TimestampGIT

Prove when your code existed

Anchors your Git commits cryptographically in the Bitcoin blockchain (OpenTimestamps) — mathematical proof of prior art, authorship and delivery dates.

Daily batching with Merkle root anchoring
GitHub App, API and CI/CD integration
Publicly verifiable proofs & status badges

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portfolio.rsj.de

Portfolio allocation

RSJ Portfolio

Stock allocation with MPT or HRP

RSJ Portfolio distributes a stock portfolio using established scientific models — Modern Portfolio Theory (MPT) or Hierarchical Risk Parity (HRP).

Modern Portfolio Theory (MPT)
Hierarchical Risk Parity (HRP)
Risk-optimized distribution of a stock portfolio

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Need more than off-the-shelf software? We build tailored solutions, too.

Software that fits your business.

Since 1985 we build custom software: mission critical, seamlessly integrated into heterogeneous systems and operated at worldwide scale — with skills from embedded to cloud.

Project work & skills

Contact

Facing a unique challenge?

Talk to us about your project — no strings attached. We look forward to hearing from you.

Write an email Schedule a video call

Phone: +49 89 89 41 42-0

We usually reply within one business day.

Video call

Book a video call directly

Pick a free slot in our calendar yourself. We meet by video — we do not schedule phone appointments.

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