A disclosure, since we are about to talk about trust.
I sell the kind of software this manifesto tells you to demand. So please read it the way you would read a locksmith's heartfelt essay on the importance of good locks: self-interested, and also correct. I have tried to write it so it stays useful even to the people I compete with, partly out of principle and partly because pretending otherwise would insult your intelligence, which is a poor way to begin.
Smart-city procurement has a peculiar quality. It is one of the few forms of shopping where the buyer routinely ends up renting back the thing they paid to own. A city spends a healthy six figures of public money on a "platform," cuts the ribbon, takes the photo, and then discovers eighteen months later that getting its own data out costs extra, or is not possible, or requires the gracious cooperation of the very vendor it would now quite like to replace. Nobody set out to engineer this. It simply happens whenever nobody writes the boring clauses.
What follows are the boring clauses, dressed up as a manifesto so you will keep reading.
1. The city owns its data.
Full stop. If you cannot export your data, in an open format, whenever you like, without asking permission or paying a toll, then you do not own it. You are renting it, from yourself, through an intermediary. This is the original sin of smart-city procurement, and every other problem here is just interest accruing on it.
2. Lock-in is a procurement failure, not a technical accident.
No vendor traps you out of malice. They trap you because the tender did not say not to, and because a captured customer is a wonderful annuity. Every proprietary format in your stack is a future invoice that has not arrived yet.
3. Negotiate the exit before you sign the entrance.
The cheapest insurance policy in public IT is an exit clause: at contract end the vendor hands over all data, schemas and documentation in open formats, and helps you migrate, at no surprise cost. You will be told this is unusual. It is. That is the problem, not the objection.
4. Require open standards. Name no products.
Write "must expose data via an open, documented standard such as NGSI-LD, or equivalent." Lawful, future-proof, competitive. Writing "must be [BrandName]" is how you get a single bidder, an inflated price, and an afternoon revisiting fair-competition law. "Or equivalent" is the most powerful four (sorry, two) words in procurement.
5. Foundations before features.
You probably do not need a data lake. A town of twenty thousand is not drowning in data, it has a tidy puddle and a filing problem. It needs a common language first, so its traffic, parking and air-quality numbers fit together. Build that, and a data lake later becomes useful. Skip it, and you have bought a reservoir to store three buckets.
6. Buy outcomes, not adjectives.
"AI-powered smart ecosystem platform" is four adjectives and zero requirements. Specify what the thing must do, and what you must be able to do with its data afterwards, and the adjectives quietly leave the room.
7. Score openness.
Do not merely tick it. A pass/fail box is the first thing value-engineered away when the price gets tight. Make openness a graded criterion worth real points, and every bidder will discover a deep and lifelong commitment to open standards.
8. Interoperability is a political choice in a technical costume.
Who can see, audit, reuse and move the city's data is not an IT detail, it is a question about who controls public infrastructure and who is accountable for public money. The EU's Interoperable Europe Act, your national strategy, and a battalion of signed declarations are all, in their patient way, on your side. (Slovenia was the first country in Europe to ask its cities to do roughly this. You may already be committed without having noticed.)
A closing note, in the same spirit of disclosure.
None of this requires you to become a technologist. It requires you to behave like a customer spending other people's money on purpose, which, said with affection, is rarer in public procurement than it ought to be. You will not get a ribbon-cutting for a good exit clause. You will simply, quietly, still own your city in five years' time. That is the whole reward, and it is enormous.
And if a vendor objects to any of the above, note which vendor, and which clause. The manifesto rather enforces itself from there.