@michiel yesterday I met with AWS and we discussed the topic shortly. AWS Greengrass can run amongst others AWS Lambda functions. It provides an option to run some computing off the amazon cloud locally. This is a useful scenario for Gateway devices that want to concentrate traffic and securely deliver this to AWS. It also provides an enabler for edge (fog) computing scenarios in which low latency is required or low bandwidth resource constraints occur. So indeed interesting but not specifically for NB-IOT.