Easier access to climate data is very important for the climate change impact research communities. Many aspects are important for those users, such as extensive guidance, transparent access to datasets, on-demand processing capabilities (notably for data reduction). To fulfill this objective, the climate4impact (http://climate4impact.eu/) web portal and services has been developed in the European Union funded IS-ENES projects, targeting climate change impact modellers, impact and adaptation consultants, as well as other experts using climate change data. It provides to users harmonized access to climate model data through tailored services. One of the main objectives of climate4impact is to provide standardized web services and tools that are reusable in other portals. These services include web processing services, web coverage services and web mapping services. Tailored portals can be targeted to specific communities and/or countries/regions while making use of those services. Recently, it became obvious that to fulfill users' needs regarding on-demand data processing and calculations, the climate4impact platform had to be able to use existing research and e-infrastructures in order to offer scalable and flexible services. This is especially true in the current context of a large increase in the data volumes of climate science datasets. To easily accommodate heterogeneous systems, a containerized and modular approach is envisioned. Finally, in the context of data processing delegation, a robust approach for metadata, provenance and lineage is required.