Lightweight trusted execution technologies for internet-of-things devices are described. In response to a memory request at a page unit from an application executing in a current domain, the page unit is to map a current virtual address (VA) to a current physical address (PA). The policy enforcement logic (PEL) reads, from a secure domain cache (SDC), a domain value (DID) and a VA value that correspond to the current PA. The PEL grants access when the current domain and the DID correspond to the unprotected region or the current domain and the DID correspond to the secure domain region, the current domain is equal to the DID, and the current VA is equal to the VA value. The PEL grants data access and denies code access when the current domain corresponds to the secure domain region and the DID corresponds to the unprotected region.