HORIZON: a Classification and Comparison Framework for Pricing-driven Feature Toggling

TL;DR

The paper tackles the challenge of managing feature access in pricing-driven SaaS environments where subscriptions tightly gate functionality. It introduces HORIZON, a capability-based framework that classifies feature toggling tools into five areas—Feature Management, Evaluation Configuration, Feature Evaluation, Integration, and Pricing-Driven Automation—to enable autonomous adaptation to pricing changes. Through validation against industrial tools and Pricing4SaaS, the work shows current solutions lack full pricing-driven support, with Pricing4SaaS fulfilling the framework's requirements while tools like LaunchDarkly and Unleash reveal notable gaps. The framework serves as a practical benchmark and a roadmap for developing more robust, pricing-aware toggle systems, offering a path toward streamlined, dynamic, and scalable pricing-driven DevOps in SaaS contexts.

Abstract

Software as a Service (SaaS) has seen rapid growth in recent years, thanks to its ability to adapt to diverse user needs through subscription-based models. However, as pricing models enhance the customization of subscriptions, managing the associated constraints within a system's codebase becomes increasingly challenging. In response, Pricing-driven Development and Operation has emerged to integrate pricing considerations across the software lifecycle. Among its most challenging objectives is regulating feature access according to users' subscriptions -- a process that requires managing a multitude of conditions throughout the system's codebase. Feature toggles have traditionally been employed to manage dynamic system behavior, but their application to pricing-driven constraints presents unique challenges. When used to enforce subscription-based restrictions, toggles must adapt -- among other factors -- to individual user's use of features, ensuring that subscription limits are not exceeded. Despite the increasing significance of this problem, current industrial solutions lack explicit support for pricing-driven feature toggling, and existing academic contributions remain constrained to specific architectures. This paper contributes to fill this gap by introducing HORIZON, a classification and comparison framework for feature toggling tools tailored to pricing-driven environments. Its utility is demonstrated by categorizing the solutions identified in the literature as promising for such environments, revealing both their strengths and limitations, and thereby pinpointing critical avenues for improvement. In doing so, HORIZON not only provides a comprehensive view of the current landscape but also lays the groundwork for a focused research agenda, guiding the development of more robust and adaptable solutions for streamlining SaaS development and operations driven by pricings.

Figures (3)

• Figure 1: Excerpt of Zoom's pricing with 11 features, three plans and three add-ons.
• Figure 2: Feature toggle evaluating a user’s plan before enabling a feature
• Figure 3: Definition of feature toggle evaluation in an external source