Release planning for incremental software development assigns features to releases such that technical, resource, risk and budget constraints are met. Planning of software releases and allocation of resources cannot be handled in isolation. A feature can be offered as part of a release only if all its necessary tasks are done before the given release date. We assume a given pool of human resources with different degrees of productivity to perform different types of tasks. To address the inherent difficulty of this process, we propose a two-phased optimization approach that combines the strength of two existing solution methods. The industrial applicability of the approach is primarily directed towards mature organizations having systematic development and measurement processes in place. The expected practical benefit of the planning method is to provide release plan solutions that achieve a better overall business value (e.g., expressed by the degree of stakeholder satisfaction) by better allocation of resources. Without ignoring the importance of the human expert in this process, the contributions of the paper are seen in making the overall process more objective and the resulting decisions more transparent.

Abstract Release planning for incremental software development assigns features to releases such that technical, resource, risk and budget constraints are met. Each feature offers a piece of functionality. A feature can be offered as part of a release only if all its necessary tasks are done before the given release date. These tasks require different skills. Staffing for product releases as considered in this paper is the process of assigning human resources from a given pool of developers who might have varying levels of skill to perform different tasks. In addition to that, we consider time windows of absence of the developers. The primary goal of staffing is to provide product releases of best quality where quality means offering the most attractive features to customers in a timely manner. We call the problem STAFF‐PRO. The problem is known to be NP‐complete. Consequently, we have to be satisfied with solutions that are sufficiently good, but not necessarily optimal in the case of mid‐sized or large problems. Search‐based methods relying on meta‐heuristics have been proven to be successful in similar contexts. In this research, a focused search (FS) method is presented. This refers to a two‐phased solution approach where Phase 1 applies integer linear programming to a relaxed version of the full problem. Its solution is used as a starting point to perform FS in a reduced search space in Phase 2. The search itself is conducted by a genetic algorithm. It generates a solution that fulfills all the stated resource and scheduling constraints and is of a proven degree of optimality. We performed an empirical analysis of the proposed solution approach by comparing FS and unfocused search (UFS) (without Phase 1) for a series of 200 test examples. On average, FS performs about 15% better than UFS. The whole method was applied as an industrial case study performed at Chartwell Technology. The case study demonstrates that application of the FS method to STAFF‐PRO (i) allows a reduction in the time needed for generating acceptable staffing plans, (ii) generates plans of proven quality that are better than manual plans and (iii) supports the various types of re‐planning necessary for varying parameters, budgets and resource. Copyright © 2008 John Wiley & Sons, Ltd.

Incremental software development is becoming an important tendency in software engineering. A software release is a collection of new and/or changed features that form a new product. Release planning for incremental software development assigns features to sequence of releases in the most beneficial way within the resources available. Release planning is a complex problem where most of the data available are usually uncertain. In this paper, we propose an approach that improves on existing methods for release planning by handling the uncertainty of data using fuzzy logic. We use fuzzy logic to model the uncertainty concerning the identification of structural dependency constraints between requirements. All the concepts and the complete approach are illustrated by a case study example