DSAL composition frameworks are tools used in the process of composing multiple DSAL mechanisms into a single multi-DSAL weaver. The DSAL composition process starts with specifying the desired interactions between the DSAL mechanisms being composed, and concludes with producing a multi-DSAL weaver which satisfies the composition specification. However, the lack of tool support for defining the composition specification, and the coding effort required in composition frameworks to implement the specification, make this process complex and error prone. This work presents a specification-based approach to DSAL composition. The approach is based on having a specifiction manifest file for the composition and for each of the individual mechanisms involved. A novel tool, named SPEC-TACKLE, analyzes the manifests and helps the composition designer define the desired specification. Based on the composition specification produced, the composition framework can generate a significant part of the implementation code for the mechanisms and for the multi-DSAL weaver. The specification-based DSAL composition process is illustrated in the context of the AWESOME composition framework.