Manual polygon digitization on maps by non-gis people creates possibility to encouter with topology exceptions and user mistakes like holes, slices and so on. We used solution to build blocks grid over Estonia so whole country is covered with various size of blocks based on versatile information like cadasters, roads and addresspoints. Result is massive arrays of relations between blocks identificators and areas. This solution creates one geospatial layer with more than million block identificators which can be used by multiple datalayers. If one block changes then all datalayers where this block were used, are affected. It offers us to discover areas which are not covered or areas which are overlapping each other. In presentation I will talk about why this idea came up, how we created block grid from data we had, how we choosed technology to build whole system and how we succeed in result. Technologies in presentation includes OpenLayers, React, Redux, GeoServer, PostgreSQL, PostGIS, Mapbox Vecor Tile, OGC Standards WFS-T, WMS, SLD and many more.