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Technical readiness is about checking to ensure that all the potential risks associated to your existing (legacy) systems are being considered and managed. It starts through awareness. Is your team aware of the issue and do you have understanding of the impacts.?
For each legacy system
is this system available externally to TC?
is there an api API to interact with the system?
will this system continue to be used or will it be replaced?
are there systems upstream/downstream that rely on this system?
list the technologies associated to the system
will the digital service need to integrate with the legacy system?
will legacy data need to be migrated from one system to another?
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Legacy systems may need to be replaced by the new service. It is necessary to do a complete and thorough analysis of the legacy system to ensure that no features of the the legacy system are overlooked. Users of a legacy should be consulted to get a complete understanding of all the features that are currently being used on the legacy system. All of those features will need to be handled by the new system.
Legacy system as a data source
Legacy systems may store data that is important and necessary for a service to function. It is often necessary in those cases to read data from the legacy system to enable a new service.
Legacy system is supplied data from a new service
A legacy system can rely on data from another system. If you are replacing a legacy system ensure that other systems that rely on it as a data source can read the required data from the new system.