Here are the classes, structs, unions and interfaces with brief descriptions:

[detail level 123]

▼NJUtils
▼NEditor
CCustomNameEditor
CRequiredEditor
CSerializeInterfaceEditor
CShowWhenEditor
CTypeSelectorEditor
CUneditableEditor
CUnpackEditor
CBaseMinMaxEditor
CMinMaxEditor
CMinMaxIntEditor
COptionalEditor
CSceneReferenceEditor
CSerializableGuidEditor
CWeightedEditor
CJUtilsInspectorButton
CEventChannelEditor
CMonoBehaviourEditor
CButtonAttribute	Attach this button to a method to make it clickable in the inspector. This attribute will also draw parameters if it can
CCustomNameAttribute	Change the name of a parameter in the inspector
CResourcePlayModeChangeCallbackReceiverAttribute	Receive a call when the play mode has been changed in a resource. Can be used to reset some data of a resource
CIResourcePlayModeChangeCallbackReceiver	This interface is optional but it gives all the methods for ResourcePlayModeChangeCallbackReceiverAttribute>
CRequiredAttribute	When an UnityEngine.Object reference has not been set, show a big warning
CSerializeInterfaceAttribute	Restrict the UnityEngine.Object field to extend a certain interface
CShowWhenAttribute	Hide a field if the condition does not match, allows checks for bools, ints, floats & strings
CTypeSelectorAttribute	Show a dropdown for all classes that extend the field's type. Requires SerializeReference attribute to function correctly
CUneditableAttribute	Disable writing for this property in the editor
CUnpackAttribute	Displays the given type in the inspector as if it isn't a different object. Useful for Unity DOTS baker workflow
CBillboardCamera	Bill-boarding component which allows for advanced anchoring and other behaviours
CDontDestroyOnLoad	Runs the DDOL function on this gameobject, this is a more declerative way to mark an object for DDOL
CDestroyObjectAfterKilled	Destroys the targetted gameobject when the attached HealthComponent died
CHealthComponent	A simple yet versatile HealthComponent implementation that uses SendMessage to send its heal & damage events
CIDamageEvent	Used to create more detailed damage events
CIHealEvent	Used to create more detailed heal events
CSimpleDamageEvent	Light simple implementation for the IDamageEvent
CSimpleHealEvent	Light simple implementation for the IHealEvent
CObjectPool	A simple implementation for an object pool
CObjectPoolManager	Makes it easier to work with object pools
CPoolItem	A behaviour that is used with the ObjectPool. Other behaviours can listen to the events this class sends
CSpawnPoolItemAfterDestroyed	Spawn an object using ObjectPoolManager after the game object was disabled / destroyed or the pool item was sent back to the object pool
CSpawnPoolItemAfterEnabled	Spawn an object using ObjectPoolManager after the game object was enalbed / created or the pool item was sent into action
CCoroutineCatcher	Wrapper for troublesome coroutines
CCoroutines	Make coroutines run on the JUtilsObject
CRoutines	A static class that contains methods for easily creating routines & avoid object allocations
CMinMax	A struct with a custom editor which can be used to get a minimum and a maximum value, handy for random values & clamping
CMinMaxInt	A struct with a custom editor which can be used to get a minimum and a maximum value, handy for random values & clamping
COptional	A struct useful for showing in the inspector if the value is optional, and does not have to be set. Also allows for quicker checks if the value is set
CRangeExtensions	Used to turn a range or int to a RangeEnumerator so it can be used in a Foreach loop
CRangeEnumerator	Allows for complex enumerations for Range types
CSceneReference	Reference a scene via its asset instead of its name. It can also give suggestions based on it being null / not in build
▼CSerializableDictionary	A dictionary of which the values do not get lost on serialization
CPair	The pair object used for the internal data
CSerializableGuid	A lightweight guid class that can be serialized
CSerializableType	Serialize a System.Type Object
CIWeighted	A interface that helps with weighted randomness WeightedExtensions
CWeighted	A struct that makes it easier to work with weighted randomness See also WeightedExtensions
CBaseEventChannel	The base class for an simple event channel
CBaseEventListener	The base class for event channel based listeners. Recommended for UI or if the GO only has one event listener, otherwise consider using the BaseEventChannel<T> directly
CBoolEventChannel
CBoolEventListener
▼CEventChannel
CEmpty
CEventChannelExtensions	Useful extensions for dealing with BaseEventChannel<T>>
CEventListener
CFloatEventChannel
CFloatEventListener
CIntEventChannel
CIntEventListener
CLongEventChannel
CLongEventListener
CUIntEventChannel
CUIntEventListener
CULongEventChannel
CULongEventListener
CAudioListenerExtensions	Adds extensions for the AudioSource component
CCollectionExtensions
CColorExtensions	Gives threshold comparing functions for Colors
CComponentExtensions	Useful extensions for working with components
CEnumerable	Extensions for Enumerates
CTransformExtensions	Some useful extensions to transforms
CUnityObjectExtensions
CVector2Extensions
CVector3Extensions
CWeightedExtensions	Contains helper functions for working with Weighted Randomness
CAssemblyJUtils	Utilities class working with assemblies
CGizmoUtils	Some shorthand functions for drawing things with Hanldes
CIService
CServiceManager	A simple service manager
CAutoSingletonBehaviour	Your simple and everyday singleton class that automatically instantiates if there is no instance yet
CISingleton	Simple interface for working with singletons
CMultitonBehaviour	A MonoBehaviour where you can easily access all of its instances
CSingletonBehaviour	Your simple and everyday singleton class
CSingletonManager	Centralized singleton to fix reference & hot reload issues issues
CState	A simple state that can be driven by stateMachine
CStateData	The data of a state
▼CStateMachine	A mono behaviour state-machine that can also be used as a state
CQueueEntry	Representation of the state and its data in the queue
CStateRef	Empty structure used to help with typesafety