1. A method of selecting software program artifact version, comprising the computer implemented steps of: in a computer: (a) enabling user development of a configuration of a subject software program in a user workspace, the subject software program configuration having a group of artifacts, and the user workspace being different from an artifact history file system storing persisted versions of the artifacts; (b) during said development, indicating a baseline version of each artifact in the subject software program configuration, said indicating resulting in a baseline indication in the user workspace; (c) providing respective activity change-set information per artifact in the subject software program configuration, said activity change-set information being indicative of activity in the user workspace, wherein, for one of the artifacts in the group, the subject software program configuration in the user workspace references one version stored in the artifact history file system as being the baseline version of the one artifact, and references a different version stored in the artifact history file system as being in at least one change-set of the one artifact, such that, during said development, the subject software program configuration in the user workspace references multiple different versions of the one artifact; further in the computer: (d) determining which one of the referenced multiple different versions of the one artifact to access in the artifact history file system upon a user accessing the one artifact in the user workspace, said determining being by the computer performing activity-based version selection of said one artifact, said computer performing using together the baseline indication and the activity change-set information to automatically determine and select, from the artifact history file system, a version of the one artifact among the multiple different versions referenced in the subject software program configuration in the user workspace, and said computer performing the activity-based version selection includes resolving any version selection error by users having used multiple versions of the one artifact during development of the subject software program configuration in the user workspace, said resolving merging versions in the artifact history file system or accepting certain change-sets into the user workspace; and displaying to the user the automatically determined and selected version of the given artifact.