Recently, we have seen an explosion in the number of devices and apps that we can use to track various aspects of our lives, such as the steps we walk, the quality of our sleep, or the calories we consume. People use devices such as the Fitbit activity tracker to increase and maintain their physical activity level by tracking their behavior, setting goals (e.g. 10'000 steps a day) and competing with friends. Many of these approaches have been shown to successfully encourage users to change their behaviors, often motivated through persuasive technologies, such as goal-setting, social encouragement and sharing mechanisms. We explored how we can map the tremendous success of these smart devices to the workplace, with the aim to increase software developers' self-awareness about productivity through self-monitoring. Yet, little is known about expectations of, the experience with, and the impact of self-monitoring in the workplace. From a mixed-methods approach we inferred design elements for building workplace self-monitoring tools, which we then implemented as a technology probe called WorkAnalytics. We field-tested these design elements during a three-week study with software development professionals. In the field study, we found that self-monitoring paired with experience sampling increases developers' awareness about work and motivates many to improve their behaviors, and that a wide variety of different metrics is needed to fulfill developers' expectations. Our work can serve as a starting point for researchers and practitioners to build self-monitoring tools for the workplace.