A model (consisting of rv-systems), a core programming language (for developing rv-programs), several specification and analysis techniques appropriate for modeling, programming and reasoning about interactive computing systems have been recently introduced by Stefanescu using register machines and space-time duality, see [Stefanescu, G. Interactive systems with registers and voices. Fundamenta Informaticae 73 (2006), 285–306. (Early draft, School of Computing, National University of Singapore, July 2004.)]. After that, Dragoi and Stefanescu have developed structured programming techniques for rv-systems and their verification, see, e.g., [Dragoi, C., and G. Stefanescu. Structured programming for interactive rv-systems. Institute of Mathematics of the Romanian Academy, IMAR Preprint 9/2006, Bucharest 2006. Dragoi, C., and G. Stefanescu. Towards a Hoare-like logic for structured rv-programs. Institute of Mathematics of the Romanian Academy, IMAR Preprint 10/2006, Bucharest, 2006. Dragoi, C., and G. Stefanescu. Implementation and verification of ring termination detection protocols using structured rv-programs. Annals of University of Bucharest, Mathematics-Informatics Series, 55 (2006), 129–138. Dragoi, C., and G. Stefanescu. Structured interactive programs with registers and voices and their verification. Draft, Bucharest, January 2007. Dragoi, C., and G. Stefanescu. On compiling structured interactive programs with registers and voices. In: “Proc. SOFSEM 2008,” 259–270. LNCS 4910, Springer, 2008.].In the present paper a kernel programming language AGAPIA v0.1 for interactive systems is introduced. The language contains definitions for complex spatial and temporal data, arithmetic and boolean expressions, modules, and while-programming statements with their temporal, spatial, and spatio-temporal versions. In AGAPIA v0.1 one can write programs for open processes located at various sites and having their temporal windows of adequate reaction to the environment. The main technical part of the paper describes a typing system for AGAPIA v0.1 programs.