OLAT is fine grained configurable, and comes with reasonable default values. In the build.properties essential settings must be configured. Everything you find under Section 4.2, “webapp/WEB-INF/” is used to customize your installation without touching java code. You can plug-in your own developed stuff as defined in various xml files found under Section 4.3, “webapp/WEB-INF/src/serviceconfig”. There is legacy configuration style (see Section 4.2, “webapp/WEB-INF/”) and the new way with Spring (see Section 4.3, “webapp/WEB-INF/src/serviceconfig”).