Simon Spoorendonk

Copenhagen, Denmark · simon@spoorendonk.dk
GitHub · LinkedIn · Google Scholar · ORCID

Plain text for agents and machines: /cv.txt.

PhD computer scientist. Three-time founder in Copenhagen, two companies acquired. Twenty years of optimization and engineering — routing, scheduling, network flow.

Peer-reviewed publications in Operations Research, Transportation Science, EJOR and Networks, plus current preprints on arXiv. 1,500+ citations, h-index 15.

Experience

• Research engineering2026–present

  Optimization and modern AI: solver libraries, published research, and systems built with AI coding agents. Preprints on arXiv: new work, and earlier papers rewritten from the ground up.

• Founder & CEO/CTO, Flowty2019–2026

  Optimization solver for planning and scheduling in logistics. Tech lead on the solver and its architecture. Delivered in production with Ørsted; pilots with DHL, Svitzer and Unifeeder.

• Co-Founder & CTO, Onlaw2017–2018

  Legal research platform built on an NLP pipeline for semantic search over unstructured documents. Acquired by Karnov Group in 2020.

• Co-Founder & CTO, Halfspace2013–2018

  AI and data science consultancy for maritime, energy and insurance. Acquired by Accenture in 2025.

• Software developer, Edlund A/S2012–2013

  Actuarial software for pension and insurance, where correct and auditable results were the product.

• Independent consultant, Freelance2011–2019

  AI and decision-support projects for insurance, pension and asset allocation clients.

• Postdoc, DTU2009–2011

  Principal investigator on a DKK 1.5M grant from the Danish Council for Independent Research. Decomposition algorithms for transportation and scheduling, in collaboration with Maersk Line.

• PhD student, University of Copenhagen2005–2008

  Thesis: Cut and Column Generation.

• Visiting PhD student, GERAD, Montréal2007

  Resource-constrained shortest path algorithms with Guy Desaulniers and Jacques Desrosiers.

• Software developer, WHO Regional Office for Europe2001–2005

• Help desk assistant, WHO Regional Office for Europe1999–2001

Advisory and teaching

• External examiner, Censorkorpset i Datalogi, Denmark2026–present

  The national external examiner corps for computer science, covering the Danish universities.

• Startup mentor, DTU Science Park2025–present

  Coaching deep-tech founders on technology choices and scaling.

• External examiner, DTU Management Engineering2012–present

  External examiner for master's theses in operations research and optimization.

• External lecturer, DTU Management Engineering2013–2014

Education

• PhD in Computer Science, University of Copenhagen2008

  Thesis: Cut and Column Generation.

• MSc in Computer Science, University of Copenhagen2005

Selected publications

• Subset-row inequalities applied to the vehicle-routing problem with time windows. M. Jepsen, B. Petersen, S. Spoorendonk, D. Pisinger. Operations Research 56(2), 2008.
• A branch-and-cut algorithm for the symmetric two-echelon capacitated vehicle routing problem. M. Jepsen, S. Spoorendonk, S. Ropke. Transportation Science 47(1), 2013.
• Liner shipping cargo allocation with repositioning of empty containers. B. D. Brouer, D. Pisinger, S. Spoorendonk. INFOR 49(2), 2011.
• A hybrid adaptive large neighborhood search heuristic for lot-sizing with setup times. L. F. Muller, S. Spoorendonk, D. Pisinger. European Journal of Operational Research 218(3), 2012.
• Cutting planes for branch-and-price algorithms. G. Desaulniers, J. Desrosiers, S. Spoorendonk. Networks 58(4), 2011.
• A branch-and-cut algorithm for the capacitated profitable tour problem. M. K. Jepsen, B. Petersen, S. Spoorendonk, D. Pisinger. Discrete Optimization 14, 2014.

Preprints

• Presolve heuristics in HiGHS: implementation and computational study. S. Spoorendonk. arXiv:2609.22938, 2026.
• An open, reproducible branch-and-cut for the capacitated profitable tour problem: a component study. S. Spoorendonk. arXiv:2607.04497, 2026.
• bucket-graph-spprc: an extensible C++ library for the shortest path problem with resource constraints. S. Spoorendonk. arXiv:2606.30847, 2026.
• A parallel pull labelling algorithm for the resource constrained shortest path problem. B. Petersen, S. Spoorendonk. arXiv:2511.01397, 2025, revised 2026.
• Tree-based formulation for the multi-commodity flow problem. S. Spoorendonk, B. Petersen. arXiv:2509.24656, 2025, revised 2026.

Open source

• bucket-graph-spprc — Header-only C++23 bucket graph labeling for the SPPRC — the pricing subproblem in vehicle routing column generation.
• cptp — Branch-and-cut solver for the Capacitated Profitable Tour Problem (CPTP) and open s–t path variants.
• coso — Typed model API + C++23 structure-aware engine for routing, scheduling, assignment, packing, network flow, lot sizing (early development).
• mcfcg — Column generation for minimum-cost multicommodity flow with path- and tree-based Dantzig-Wolfe decompositions.
• mip-heuristics — Four MIP presolve heuristics (FeasibilityJump, FPR, LocalMIP, Scylla) implemented and benchmarked inside HiGHS.
• cbls — Constraint-based local search (ViolationLS) for mixed discrete-continuous optimization — C++23 with Python bindings.
• mipx — A from-scratch branch-and-cut MIP solver in C++23 with Python bindings (early development).
• md2mip — Compile natural-language optimization models into standalone solver CLIs (Python + HiGHS).