nev is a web-based visual tool for querying and inspection of Nemo‘s reasoning traces.

Screenshot of the three main components of the visual tool nev.

Screenshot of nev’s 3 main components: A central main tree view of the current query trace where modifications lead to new queries, an indented tree view on the left to facilitate navigation of the trace, and tabular views at the bottom for more details per query node.

Prototype: Run the Application

Video: Tool Walkthrough

Related Publications

  • Declarative Debugging for Datalog with Aggregation

    Declarative Debugging for Datalog with Aggregation

    Dachselt, R.; Gerlach, L.; Hanisch, P.; Ivliev, A.; Krötzsch, M.; Marx, M.; Méndez, J.

    To appear in Proceedings of the Workshops of the EDBT/ICDT 2026 Joint Conference.EDBT/ICDT-WS 2026, Tampere, Finland.CEUR-WS.org,2026.

    @inproceedings{DGHIKMM2026,
       author = {Raimund Dachselt and Lukas Gerlach and Philipp Hanisch and Alex Ivliev and Markus Kr\"{o}tzsch and Maximilian Marx and Juli\'{a}n M\'{e}ndez},
       title = {Declarative Debugging for Datalog with Aggregation},
       booktitle = {Proceedings of the Workshops of the EDBT/ICDT 2026 Joint Conference},
       series = {CEUR Workshop Proceedings},
       year = {2026},
       month = {3},
       location = {Tampere, Finland},
       numpages = {8},
       publisher = {CEUR-WS.org}
    }

    List of additional material

  • EvonNemo - A Symbiosis of Datalog Tracing and Proof Tree Visualization

    EvonNemo - A Symbiosis of Datalog Tracing and Proof Tree Visualization

    Gerlach, L.; Ivliev, A.; Méndez, J.; Meusel, S.; Dachselt, R.; Krötzsch, M.

    In The Fifth Workshop on Explainable Logic-Based Knowledge Representation.XLoKR '24, Hanoi, Vietnam.2024.

    @article{gerlach2024evonnemo,
       author = {Lukas Gerlach and Alex Ivliev and Juli\'{a}n M\'{e}ndez and Simon Meusel and Raimund Dachselt and Markus Kr\"{o}tzsch},
       title = {EvonNemo - A Symbiosis of Datalog Tracing and Proof Tree Visualization},
       booktitle = {The Fifth Workshop on Explainable Logic-Based Knowledge Representation},
       year = {2024},
       month = {11},
       location = {Hanoi, Vietnam}
    }

    List of additional material

Related Student Theses

  • Tobias Wieland

    Interactive Visualization for Datalog Query Tracing

    Tobias Wieland April 28th, 2025 until September 15th, 2025

    Supervision: Julián Méndez, Raimund Dachselt

Acknowledgements

This work was supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy: EXC-2068, 390729961 – Cluster of Excellence “Physics of Life” and EXC 2050/2, 390696704 – Cluster of Excellence “Centre for Tactile Internet” (CeTI) of TU Dresden, by DFG grant 389792660 as part of TRR 248 – CPEC (see https://cpec.science) and by the Federal Ministry of Research, Technology and Space (BMFTR, SCADS22B) and Saxon State Ministry for Science, Culture and Tourism (SMWK) by funding the competence center for Big Data and AI “ScaDS.AI Dresden/Leipzig”.