To fill this gap in the chemoinformatics landscape, we present a chemical expert system that will take for chemical routes and networks the role that toolkits like OpenBabel, RDKit, and CDK play for molecules. LinChemIn captures the Linked Chemical Information that underlies chemical reaction data and allows managing entities of chemical relevance, such as the synthetic chemical route. Besides the interconversion of file formats and data models, the toolkit enables route-level analysis and operations, including network editing, descriptor calculations, topological and chemical route comparisons, and searches. On the one hand, application scientists can conveniently access the toolkit functionalities via command-line interfaces (CLIs) and front-facing high-level software components. On the other hand, developers of third-party applications can access lower-level modules to obtain complete control of the toolkit functionalities. Besides these two user categories, we designed the toolkit architecture to encourage scientists and developers to contribute to its code base. The first release of LinChemIn constitutes an open and extensible framework capable of incorporating contributions from the scientific community. Following the AGILE approach to software development, the early publication of a minimal viable product should stimulate scientific discussions and provide valuable steers to further improvements. While pursuing an active development roadmap, we will progressively release new modules that enable new functionalities.