Lead Backend Engineer

You'll build the backend APIs and mathematical core of our design engine, developing optimisation models, geometric algorithms, and simulation systems that translate extracted plan information into physically valid, optimised 3D building structures, all while capturing the real-world constraints of residential construction and serving these models to our applications. Your work will power the engine that turns drawings into buildable designs.
Responsibilities:
Build APIs and services to provide conduction design models to frontend applications using Python and FastAPI.
Design and implement optimisation models using operations research techniques, including constrained programming, linear programming, and mixed-integer programming (MIP).
Develop computational geometry systems that convert plan-derived data into structured 3D building representations.
Build simulation and constraint systems that model real-world construction rules, structural relationships, and material layouts.
Develop production-grade Python systems that solve large-scale optimisation and geometric problems.
Improve performance and scalability of heavy mathematical workloads through algorithm design, solver tuning, and profiling.
Work closely with ML engineers and platform engineers to integrate optimisation systems into the broader plan ingestion and design pipeline.
Ensure mathematical systems are reliable, testable, maintainable, and production-ready.
Requirements:
5 - 6 years of experience developing mathematical or optimisation systems in production environments.
Expert Python programming skills with experience building complex numerical or algorithmic systems.
Strong background in operations research, constrained optimisation, linear programming, or mixed-integer programming.
Strong understanding of algorithm design, computational complexity, and performance optimisation.
Experience implementing or working with computational geometry algorithms.
Comfortable working in Linux environments and deploying production systems.
Good to Have:
High agency: you take ownership of difficult systems and drive them to production.
You enjoy translating messy real-world rules into clean mathematical formulations.
You care deeply about performance, determinism, and correctness.
You are comfortable operating independently in a fast-paced engineering environment.
You communicate clearly and collaborate well with engineers across disciplines.
Bonus Points:
Experience with OR solvers (Gurobi, CPLEX, SCIP, OR-Tools).
Background in computational geometry, geometric modelling, or spatial algorithms.
Experience building large-scale optimisation systems.
Familiarity with performance optimisation in numerical or simulation workloads.
Familiarity with the construction, CAD, or manufacturing domains.

Experience
5-6 yrs