anchor.diff:          end
   
   /// A collection of component stores.
  -and 'w Archetype (storeTypes : Dictionary<string, Type>, terms : Dictionary<string, Term>) =
  +and 'w Archetype (terms : Dictionary<string, Term>) =
   
       let mutable freeIndex = 0
       let freeList = hashSetPlus<int> HashIdentity.Structural []
       let stores = dictPlus<string, Store> HashIdentity.Structural []
  -    let id = { ComponentNames = hashSetPlus HashIdentity.Structural storeTypes.Keys; Terms = terms }
  -
  -    do
  -        let storeTypeGeneric = typedefof<EntityId Store>
  -        for storeTypeEntry in storeTypes do
  -            let storeType = storeTypeGeneric.MakeGenericType [|storeTypeEntry.Value|]
  -            let store = Activator.CreateInstance (storeType, storeTypeEntry.Key) :?> Store
  -            stores.Add (storeTypeEntry.Key, store)
  +    let id = { Terms = terms }
   
       do
           let storeTypeGeneric = typedefof<EntityId Store>
  
positive.code:                     archetypeSlots.Add (entityId, { ArchetypeIndex = archetypeIndex; Archetype = archetype })
                      world
                  | (false, _) ->
                      let archetype = createArchetype typeof<unit> archetypeId
                      let archetypeIndex = archetype.Register comps
                      archetypeSlots.Add (entityId, { ArchetypeIndex = archetypeIndex; Archetype = archetype })
                      world
              let eventData = { EntityId = entityId; ContextName = termName }
              this.Publish EcsEvents.Register eventData world
  
      member this.UnregisterTag termName entityId world =
          match archetypeSlots.TryGetValue entityId with
          | (true, archetypeSlot) ->
              let archetype = archetypeSlot.Archetype
  
negative.code: /// Identifies an archetype.
  /// TODO: consider embedding hash code to make look-ups faster.
  type [<CustomEquality; NoComparison>] ArchetypeId =
      { Terms : Dictionary<string, Term> }
  
      static member inline Hash (dict : Dictionary<_, _>) =
          let mutable h = 0
  