Technology Radar
A published, periodically revised classification of technologies into adopt, trial, assess and hold, giving guidance without issuing a mandate.
A radar occupies the useful middle ground between a rigid approved-technology list, which teams resent and route around, and no guidance at all, which produces an estate with nine message brokers.
The four rings carry distinct meanings that should be respected. Adopt means this is the default and you need a reason not to use it. Trial means it is worth using in a project that can absorb risk. Assess means it is worth understanding but not yet worth building on. Hold means do not start anything new with it, which is deliberately different from banning it — existing systems are not required to migrate.
What makes a radar work rather than decorate an intranet page. It must be specific — naming technologies rather than categories — and it must justify each placement in a sentence or two, because the reasoning is what teams actually use. It must be revised on a cadence, or it becomes a snapshot of what the architecture team liked two years ago. And it should reflect what is genuinely in use and supported internally, since a technology in Adopt with no internal expertise, no paved road and no operational support is a recommendation the organisation cannot honour.
The strongest version pairs each Adopt entry with a golden path that makes it the easiest option, at which point the radar describes reality rather than instructing it.