Redux Immutable State Invariant Middleware

Redux-immutable-state-invariant is a specialized Redux middleware designed exclusively for development environments. Its core function is to detect unintended mutations of the Redux state, both within a reducer's dispatch cycle and between dispatches. This is crucial for upholding the immutability principle central to Redux, preventing subtle bugs that arise from direct state modification rather than returning new state objects. The current stable version is 2.1.0, with a release cadence that has seen significant updates around v1 and v2, and more recently a minor bug fix in v2.1.0, indicating ongoing maintenance. Unlike libraries like Immutable.js which provide immutable data structures, this middleware acts as a runtime check for native JavaScript objects and arrays, throwing descriptive errors when mutations are detected. It is explicitly warned against using in production due to its performance overhead caused by extensive object copying for comparison.