engine · v0An engine of Project Flânerie

Saunteur.

An engine for finding your way.

Saunteur is the engine underneath Urban Gallery. Given a collection of things worth attending to, a way to compare them, a cost between them, and a budget, it produces an ordered itinerary that maximises total value within that budget.

01 · The shape of the engine

Four inputs and an output. The same shape regardless of what’s in the corpus.

01 · corpus
A collection of things
sculpturestracksessaysbreweriescorridors
02 · comparator
A way to compare
value(a, b)relevancefit
03 · cost
A cost between
meterssecondswordsminutes
04 · budget
A budget to spend
2h afternoon45m playlist4-day traverse
→ output
Ordered itinerary
max valuewithin budgetwalk-friendly

02 · Domain tests

If a domain encodes as a corpus and a configuration, the abstraction is real.

Saunteur grew up solving one problem: a public-art walking tour. Items are sculptures; distance is meters between them; budget is two hours of an afternoon; value is “pieces seen.” But none of that is baked in. We deliberately tested the engine against distant problems to find out whether the abstraction was real, or whether the picker would have to fork.

Chill 45-minute playlist

A track sequence from a music library, paced for the listening window and the mood.

corpus: librarycost: secondsbudget: 45m

Focused reading itinerary

An ordered path across a corpus of essays. Same shape; cost is now words; value is fit.

corpus: essayscost: wordsbudget: 90m

Brewery walking tour

A neighborhood loop on foot. Walking minutes, ratings, and which spots you've already visited — all in the cost.

corpus: breweriescost: minutesbudget: 4h

Four-day Highland traverse

A sequence of single-day corridors, with state threaded between days. No multi-day machinery.

corpus: corridorscost: minutesbudget: 4 days

The same algorithm runs all of these without a fork. If the picker had to fork, the abstraction wouldn’t be real.

03 · What the work has taught us so far

Three things we’ve learned, pushing the engine against unfamiliar problems.

findingI

A "tour" is more general than it sounds.

The same algorithmic shape — score against distance, walk down possible tour lengths until one fits, then improve it locally — applies whether the cost is meters of walking, seconds of audio, or attention spent on a paragraph.

findingII

Locality bias matters more in some domains than others.

At walking distances it’s a feature; at driving distances it becomes a bug. The right escape mechanism depends on whether the user wants coherence (a focused reading session) or spread (a multi-neighborhood brewery trip).

findingIII

Multi-day composition needs no special machinery.

A four-day traverse is a sequence of single-day corridors with state threaded between days. The engine doesn’t need to know it’s multi-day.

04 · Honest measurement

Benchmarked against the academic Orienteering Problem literature.

We benchmark Saunteur against the corner of optimisation research closest to this kind of problem. It runs near-ceiling on the classical proven-optima suites and shows documented headroom against modern specialised heuristics on the larger OPLib suite.

The point of running the benchmarks isn’t credentials. It’s a check on our own work — a way to know whether the engine is sound before pointing it at problems where the optimum isn’t known.

Suite · Result
Tsiligirides 1984
classical, proven optima
near-ceiling
Fischetti 1998
classical, proven optima
near-ceiling
OPLib
modern, specialised heuristics
+ headroom

Detailed methodology & per-instance numbers available on request. The engine is unmodified between suites.

05 · Status

Currently a Back Room Strategies project. Not generally available. Yet.

Saunteur lives inside the firm for now. The next milestone is Urban Gallery’s migration onto Saunteur as its production engine — the case it grew up solving, finally running on the abstraction.

Direct availability is on the horizon. The likely shape is industry-specific engine integrations into existing apps, rather than a general-purpose library.

Now
Internal engine, benchmarked, deliberate domain tests
Next
Urban Gallery migration onto Saunteur as production engine
Then
Selected industry partnerships & engine integrations

06 · Inquiries

Partnership, evaluation, or licensing.

For partnership conversations, technical evaluation, or licensing inquiries — write directly. A short note about the problem and the shape of the data gets a real reply.