-Eraso et al.; Revista Facultad de Ingeniería, No. 80, pp. 97-108, 2016 compatible. In WAFs, this layer has been called Object Relational Mapping (ORM). The ORMs map data from DB to OOP, allowing programmers to query DB records in a simple and powerful way without changing the OOP program point of view.As mappings, ORMs can be used as abstraction barriers [9] between relational DBs and OOP programs. This is possible because, changes in the OOP or in the DB models affect the mapping function only, preventing them from propagating to the other side. Consequently, using ORMs is an important maintainability factor.The maintainability benefits of ORMs have been included in most WAFs as a "off the shelf" pre-coded component. Unfortunately, off the shelf ORMs might threaten the overall application performance. In fact, when a programmer builds his own ORM, he is free to tailor it to the program, applying specific efficiency criteria to improve the query performance; in contrast, off the shelf ORMs craft the queries in a standardized way, making harder to achieve the same specific efficiency.Consequently, using off the shelve ORMs creates tension between maintainability and performance. On one hand, they ease the task of developing websites controlling the complexity of the software specification; on the other hand, Hibernate and spring -An analysis of maintainability against performance ABSTRACT: Web application frameworks and ORM tools reduce time and effort needed when developing quality applications; but, since they are numerous and heterogeneous choosing the best suited is not an easy task. The comparative studies of these tools do not consider case studies of the necessary complexity to precisely measure their advantages and disadvantages. In order to contribute to the solution of this problem, we measured the HIBERNATE ORM response times for different queries in a rather complex case study with different database sizes, and compared the results with the ones obtained by using manually coded queries. Our comparison is relevant because even though ORMs are an important maintainability factor, not optimal queries can lead to bottle necks. RESUMEN:Los frameworks para el desarrollo de aplicaciones web y las herramientas ORM permiten reducir el tiempo y esfuerzo al producir aplicaciones de software de calidad. Se han hecho estudios comparativos sobre estas herramientas pero dado que son numerosas y heterogéneas, escoger la más adecuada no es fácil. Hay estudios comparativos sobre estas herramientas, sin embargo no consideraron un dominio suficientemente complejo que permitan medir más precisamente sus ventajas y desventajas. Para aportar en la solución, comparamos el tiempo de respuesta de diferentes consultas en un dominio más complejo y con diferentes tamaños de base de datos. La comparación basada en este aspecto es importante ya que los ORM son un factor de mantenibilidad importante y porque consultas no optimizadas pueden conducir a cuellos de botella.