Before that, he worked as a policy consultant at the Friedrich-Ebert-Stiftung (FES). His research covers issues of European integration, in particular economic and social integration. Professor Hacker has steered research projects on reform of the European Economic and Monetary Uni- on, policy coordination in the EU and the European Pillar of Social Rights. He has published numerous papers, articles and book chapters. His doctoral thesis was on the Open Method of Coordination in the pension sector (published in German in 2010).

He studied economics and political sciences at the University of Osnabrück, the University of Barcelona and Sciences Po Paris, where he obtained his Master’s degree. At HTW Berlin Hacker teaches macroeconomics, the EU political system, EU integration theories and international relations. Recently, he established a joint degree study programme in European economic policy. Hacker has been liaison officer for the Hans-Böckler-Stiftung (HBS) since 2016 and a member of the academic advisory board of the Institut für Europäische Politik (IEP) since 2018.