diff --git a/app/models/problem.py b/app/models/problem.py
index 879e10c..5c6f75d 100644
--- a/app/models/problem.py
+++ b/app/models/problem.py
@@ -60,7 +60,7 @@ class Problem(BaseModel):
                 # get items from solution
                 solved_items, _ = service_helper.solution_items(self.problem.variables(), solver_run)
 
-                # sacred items will remain the same between solve attempts
+                # sacred items will remain the same (with new items added each run) between solve attempts
                 # but new enemies will be appended
                 sacred_ids, new_enemy_ids = sanctify(solved_items)
 
diff --git a/app/models/solver_run.py b/app/models/solver_run.py
index 02653db..ff320a5 100644
--- a/app/models/solver_run.py
+++ b/app/models/solver_run.py
@@ -1,9 +1,8 @@
 from __future__ import annotations
-from typing import TYPE_CHECKING
-
+from typing import TYPE_CHECKING, List, Literal, Optional, Union, TypeVar
 from pulp import lpSum
 from pydantic import BaseModel
-from typing import List, Literal, Optional, Union
+
 
 import logging
 
@@ -22,11 +21,13 @@ if TYPE_CHECKING:
     from models.solution import Solution
     from models.problem import Problem
 
+ConstraintType = TypeVar('ConstraintType', bound=GenericConstraint)
+
 class SolverRun(BaseModel):
     items: List[Item] = []
     bundles: List[Bundle] = []
     bundle_first_ordering: bool = True
-    constraints: List[Union[GenericConstraint, MetadataConstraint, BundleConstraint, FormUniquenessConstraint, TotalFormItemsConstraint]]
+    constraints: List[ConstraintType]
     irt_model: IRTModel
     objective_function: ObjectiveFunction
     total_form_items: int
@@ -42,7 +43,7 @@ class SolverRun(BaseModel):
 
         # this is all a compensator for dynamically creating objects
         # ideally we'd change the payload to determine what type it is
-        constraints: [GenericConstraint|MetadataConstraint|BundleConstraint|FormUniquenessConstraint|TotalFormItemsConstraint] = []
+        constraints: [ConstraintType] = []
 
         # total form items
         constraints.append(TotalFormItemsConstraint.create(self.total_form_items))
@@ -70,7 +71,7 @@ class SolverRun(BaseModel):
             if bundle.id == bundle_id:
                 return bundle
 
-    def get_constraint_by_type(self, type: str) -> GenericConstraint|MetadataConstraint|BundleConstraint|FormUniquenessConstraint|TotalFormItemsConstraint or None:
+    def get_constraint_by_type(self, type: str) -> ConstraintType or None:
         for constraint in self.constraints:
             if type == constraint.reference_attribute.type:
                 return constraint
@@ -131,7 +132,7 @@ class SolverRun(BaseModel):
 
         logging.info('Bundles Generated...')
 
-    def get_constraint(self, name: str) -> GenericConstraint|MetadataConstraint|BundleConstraint|FormUniquenessConstraint|TotalFormItemsConstraint:
+    def get_constraint(self, name: str) -> ConstraintType:
         return next((constraint for constraint in self.constraints
                      if constraint.reference_attribute.id == name), None)