diff --git a/docs/data_structures/alloc_specs.rst b/docs/data_structures/alloc_specs.rst
index 074c6a152..159b9eaca 100644
--- a/docs/data_structures/alloc_specs.rst
+++ b/docs/data_structures/alloc_specs.rst
@@ -19,7 +19,7 @@ Can be constructed and passed to libEnsemble as a Python class or a dictionary.
   * libEnsemble uses the following defaults if the user doesn't provide their own ``alloc_specs``:
 
   ..  literalinclude:: ../../libensemble/specs.py
-      :start-at: alloc_f: Callable = give_sim_work_first
+      :start-at: alloc_f: Callable = start_only_persistent
       :end-before: end_alloc_tag
       :caption: Default settings for alloc_specs
 
diff --git a/docs/examples/alloc_funcs.rst b/docs/examples/alloc_funcs.rst
index f54f4bf3c..3734d7cb0 100644
--- a/docs/examples/alloc_funcs.rst
+++ b/docs/examples/alloc_funcs.rst
@@ -10,14 +10,31 @@ Many users use these unmodified.
 .. IMPORTANT::
   See the API for allocation functions :ref:`here<api_alloc_f>`.
 
+  **The default allocation function changed in libEnsemble v2.0 from `give_sim_work_first` to `start_only_persistent `.**
+
 .. note::
-   The default allocation function (for non-persistent generators) is :ref:`give_sim_work_first<gswf_label>`.
 
-   The most commonly used (for persistent generators) is :ref:`start_only_persistent<start_only_persistent_label>`.
+   The default allocation function for persistent generators is :ref:`start_only_persistent<start_only_persistent_label>`.
+
+   The most commonly used allocation function for non-persistent generators is :ref:`give_sim_work_first<gswf_label>`.
 
 .. role:: underline
     :class: underline
 
+.. _start_only_persistent_label:
+
+start_only_persistent
+---------------------
+.. automodule:: start_only_persistent
+  :members:
+  :undoc-members:
+
+.. dropdown:: :underline:`start_only_persistent.py`
+
+   .. literalinclude:: ../../libensemble/alloc_funcs/start_only_persistent.py
+      :language: python
+      :linenos:
+
 .. _gswf_label:
 
 give_sim_work_first
@@ -44,20 +61,6 @@ fast_alloc
       :language: python
       :linenos:
 
-.. _start_only_persistent_label:
-
-start_only_persistent
----------------------
-.. automodule:: start_only_persistent
-  :members:
-  :undoc-members:
-
-.. dropdown:: :underline:`start_only_persistent.py`
-
-   .. literalinclude:: ../../libensemble/alloc_funcs/start_only_persistent.py
-      :language: python
-      :linenos:
-
 start_persistent_local_opt_gens
 -------------------------------
 .. automodule:: start_persistent_local_opt_gens
diff --git a/docs/function_guides/allocator.rst b/docs/function_guides/allocator.rst
index a65c404ab..062010582 100644
--- a/docs/function_guides/allocator.rst
+++ b/docs/function_guides/allocator.rst
@@ -128,8 +128,8 @@ The remaining values above are useful for efficient filtering of H values
 
 Descriptions of included allocation functions can be found :doc:`here<../examples/alloc_funcs>`.
 The default allocation function is
-``give_sim_work_first``. During its worker ID loop, it checks if there's unallocated
+``start_only_persistent``. During its worker ID loop, it checks if there's unallocated
 work and assigns simulations for that work. Otherwise, it initializes
 generators for up to ``"num_active_gens"`` instances. Other settings like
 ``batch_mode`` are also supported. See
-:ref:`here<gswf_label>` for more information about ``give_sim_work_first``.
+:ref:`here<start_only_persistent_label>` for more information.
diff --git a/libensemble/specs.py b/libensemble/specs.py
index dac1baae4..ca02586dd 100644
--- a/libensemble/specs.py
+++ b/libensemble/specs.py
@@ -5,7 +5,7 @@
 import pydantic
 from pydantic import BaseModel, Field, model_validator
 
-from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
+from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens
 
 __all__ = ["SimSpecs", "GenSpecs", "AllocSpecs", "ExitCriteria", "LibeSpecs", "_EnsembleSpecs"]
 
@@ -265,10 +265,14 @@ class AllocSpecs(BaseModel):
     Specifications for configuring an Allocation Function.
     """
 
-    alloc_f: object = give_sim_work_first
+    alloc_f: object = only_persistent_gens
     """
     Python function matching the ``alloc_f`` interface. Decides when simulator and generator functions
     should be called, and with what resources and parameters.
+
+    .. note::
+        For libEnsemble v2.0, the default allocation function is now ``only_persistent_gens``, instead
+        of ``give_sim_work_first``.
     """
 
     user: dict | None = {"num_active_gens": 1}
diff --git a/libensemble/tests/functionality_tests/1d_sampling.json b/libensemble/tests/functionality_tests/1d_sampling.json
index 6066cdd69..0acb17252 100644
--- a/libensemble/tests/functionality_tests/1d_sampling.json
+++ b/libensemble/tests/functionality_tests/1d_sampling.json
@@ -28,5 +28,8 @@
     "user": {
       "gen_batch_size": 500
     }
+  },
+  "alloc_specs": {
+    "alloc_f": "libensemble.alloc_funcs.give_sim_work_first.give_sim_work_first"
   }
 }
diff --git a/libensemble/tests/functionality_tests/1d_sampling.toml b/libensemble/tests/functionality_tests/1d_sampling.toml
index 6618019a6..bd1ddb8aa 100644
--- a/libensemble/tests/functionality_tests/1d_sampling.toml
+++ b/libensemble/tests/functionality_tests/1d_sampling.toml
@@ -20,3 +20,6 @@
       size = 1
   [gen_specs.user]
     gen_batch_size = 500
+
+[alloc_specs]
+  alloc_f = "libensemble.alloc_funcs.give_sim_work_first.give_sim_work_first"
diff --git a/libensemble/tests/functionality_tests/1d_sampling.yaml b/libensemble/tests/functionality_tests/1d_sampling.yaml
index 3e82548ae..904c55403 100644
--- a/libensemble/tests/functionality_tests/1d_sampling.yaml
+++ b/libensemble/tests/functionality_tests/1d_sampling.yaml
@@ -22,3 +22,6 @@ gen_specs:
             size: 1
     user:
         gen_batch_size: 500
+
+alloc_specs:
+    alloc_f: libensemble.alloc_funcs.give_sim_work_first.give_sim_work_first
diff --git a/libensemble/tests/functionality_tests/test_1d_sampling_no_comms_given.py b/libensemble/tests/functionality_tests/test_1d_sampling_no_comms_given.py
index 563ee920e..0a3594587 100644
--- a/libensemble/tests/functionality_tests/test_1d_sampling_no_comms_given.py
+++ b/libensemble/tests/functionality_tests/test_1d_sampling_no_comms_given.py
@@ -17,11 +17,12 @@
 import numpy as np
 
 from libensemble import Ensemble
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 
 # Import libEnsemble items for this test
 from libensemble.sim_funcs.simple_sim import norm_eval as sim_f
-from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 from libensemble.tools import check_npy_file_exists
 
 # Main block is necessary only when using local comms with spawn start method (default on macOS and Windows).
@@ -55,6 +56,7 @@
     )
 
     sampling.add_random_streams()
+    sampling.alloc_specs = AllocSpecs(alloc_f=give_sim_work_first)
     H, persis_info, flag = sampling.run()
 
     if sampling.is_manager:
diff --git a/libensemble/tests/functionality_tests/test_1d_sampling_with_profile.py b/libensemble/tests/functionality_tests/test_1d_sampling_with_profile.py
index 645228d13..8ca5fca76 100644
--- a/libensemble/tests/functionality_tests/test_1d_sampling_with_profile.py
+++ b/libensemble/tests/functionality_tests/test_1d_sampling_with_profile.py
@@ -19,6 +19,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 from libensemble.libE import libE
 from libensemble.sim_funcs.simple_sim import norm_eval as sim_f
@@ -50,10 +51,16 @@
 
     persis_info = add_unique_random_streams({}, nworkers + 1)
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     exit_criteria = {"sim_max": 501}
 
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert len(H) >= 501
diff --git a/libensemble/tests/functionality_tests/test_1d_splitcomm.py b/libensemble/tests/functionality_tests/test_1d_splitcomm.py
index de73660d7..d0c47129b 100644
--- a/libensemble/tests/functionality_tests/test_1d_splitcomm.py
+++ b/libensemble/tests/functionality_tests/test_1d_splitcomm.py
@@ -15,6 +15,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 
 # Import libEnsemble items for this test
@@ -51,12 +52,18 @@
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1, seed=1234)
 
     exit_criteria = {"gen_max": 501}
 
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert len(H) >= 501
diff --git a/libensemble/tests/functionality_tests/test_1d_subcomm.py b/libensemble/tests/functionality_tests/test_1d_subcomm.py
index 7f607c31c..0810f12e8 100644
--- a/libensemble/tests/functionality_tests/test_1d_subcomm.py
+++ b/libensemble/tests/functionality_tests/test_1d_subcomm.py
@@ -15,6 +15,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 
 # Import libEnsemble items for this test
@@ -55,12 +56,18 @@
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1, seed=1234)
 
     exit_criteria = {"gen_max": 501}
 
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert len(H) >= 501
diff --git a/libensemble/tests/functionality_tests/test_1d_super_simple.py b/libensemble/tests/functionality_tests/test_1d_super_simple.py
index e84255714..326e6abce 100644
--- a/libensemble/tests/functionality_tests/test_1d_super_simple.py
+++ b/libensemble/tests/functionality_tests/test_1d_super_simple.py
@@ -15,6 +15,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 
 # Import libEnsemble items for this test
@@ -55,7 +56,13 @@ def sim_f_noreturn(In):
 
     exit_criteria = {"gen_max": 501}
 
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert len(H) >= 501
diff --git a/libensemble/tests/functionality_tests/test_1d_uniform_sampling_with_comm_dup.py b/libensemble/tests/functionality_tests/test_1d_uniform_sampling_with_comm_dup.py
index 7d2d9f588..98b738e69 100644
--- a/libensemble/tests/functionality_tests/test_1d_uniform_sampling_with_comm_dup.py
+++ b/libensemble/tests/functionality_tests/test_1d_uniform_sampling_with_comm_dup.py
@@ -19,6 +19,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 
 # Import libEnsemble items for this test
@@ -62,8 +63,12 @@
 
     exit_criteria = {"gen_max": 501}
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs)
 
     if is_manager:
         # assert libE_specs["comms"] == "mpi", "MPI default comms should be set"
diff --git a/libensemble/tests/functionality_tests/test_calc_exception.py b/libensemble/tests/functionality_tests/test_calc_exception.py
index 361e1be3a..d435be283 100644
--- a/libensemble/tests/functionality_tests/test_calc_exception.py
+++ b/libensemble/tests/functionality_tests/test_calc_exception.py
@@ -13,6 +13,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
 from libensemble.manager import LoggedException
@@ -47,6 +48,10 @@ def six_hump_camel_err(H, persis_info, sim_specs, _):
 
     persis_info = add_unique_random_streams({}, nworkers + 1)
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     exit_criteria = {"wallclock_max": 10}
 
     libE_specs["abort_on_exception"] = False
@@ -54,7 +59,9 @@ def six_hump_camel_err(H, persis_info, sim_specs, _):
     # Perform the run
     return_flag = 1
     try:
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+        H, persis_info, flag = libE(
+            sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+        )
     except LoggedException as e:
         print(f"Caught deliberate exception: {e}")
         return_flag = 0
diff --git a/libensemble/tests/functionality_tests/test_comms.py b/libensemble/tests/functionality_tests/test_comms.py
index 52c3e0771..ca31f18e0 100644
--- a/libensemble/tests/functionality_tests/test_comms.py
+++ b/libensemble/tests/functionality_tests/test_comms.py
@@ -16,6 +16,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor  # Only used to get workerID in float_x1000
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 
@@ -55,8 +56,14 @@
 
     exit_criteria = {"sim_max": sim_max, "wallclock_max": 300}
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert flag == 0
diff --git a/libensemble/tests/functionality_tests/test_evaluate_existing_plus_gen.py b/libensemble/tests/functionality_tests/test_evaluate_existing_plus_gen.py
index fe3d8dad8..474aa18f9 100644
--- a/libensemble/tests/functionality_tests/test_evaluate_existing_plus_gen.py
+++ b/libensemble/tests/functionality_tests/test_evaluate_existing_plus_gen.py
@@ -18,9 +18,10 @@
 
 # Import libEnsemble items for this test
 from libensemble import Ensemble
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 from libensemble.sim_funcs.six_hump_camel import six_hump_camel as sim_f
-from libensemble.specs import ExitCriteria, GenSpecs, SimSpecs
+from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, SimSpecs
 from libensemble.tools import add_unique_random_streams
 
 
@@ -59,6 +60,7 @@ def create_H0(persis_info, gen_specs, H0_size):
     sampling.exit_criteria = ExitCriteria(sim_max=100)
     sampling.persis_info = add_unique_random_streams({}, sampling.nworkers + 1)
     sampling.H0 = create_H0(sampling.persis_info, gen_specs, 50)
+    sampling.alloc_specs = AllocSpecs(alloc_f=give_sim_work_first)
     sampling.run()
 
     if sampling.is_manager:
diff --git a/libensemble/tests/functionality_tests/test_executor_hworld_pass_fail.py b/libensemble/tests/functionality_tests/test_executor_hworld_pass_fail.py
index 1b61bf8d2..b59f9b27b 100644
--- a/libensemble/tests/functionality_tests/test_executor_hworld_pass_fail.py
+++ b/libensemble/tests/functionality_tests/test_executor_hworld_pass_fail.py
@@ -15,6 +15,7 @@
 import numpy as np
 
 import libensemble.sim_funcs.six_hump_camel as six_hump_camel
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
@@ -88,8 +89,12 @@
     # num sim_ended_count conditions in executor_hworld
     exit_criteria = {"sim_max": nworkers * 5}
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs)
 
     if is_manager:
         print("\nChecking expected task status against Workers ...\n")
diff --git a/libensemble/tests/functionality_tests/test_executor_hworld_timeout.py b/libensemble/tests/functionality_tests/test_executor_hworld_timeout.py
index 496eced31..16e74e300 100644
--- a/libensemble/tests/functionality_tests/test_executor_hworld_timeout.py
+++ b/libensemble/tests/functionality_tests/test_executor_hworld_timeout.py
@@ -15,6 +15,7 @@
 import numpy as np
 
 import libensemble.sim_funcs.six_hump_camel as six_hump_camel
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 
@@ -85,6 +86,10 @@
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1)
 
     exit_criteria = {"wallclock_max": 10}
@@ -97,7 +102,9 @@
 
     for i in range(iterations):
         # Perform the run
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+        H, persis_info, flag = libE(
+            sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs
+        )
 
         if is_manager:
             print("\nChecking expected task status against Workers ...\n")
diff --git a/libensemble/tests/functionality_tests/test_executor_simple.py b/libensemble/tests/functionality_tests/test_executor_simple.py
index ac4c201a7..729b1ddf6 100644
--- a/libensemble/tests/functionality_tests/test_executor_simple.py
+++ b/libensemble/tests/functionality_tests/test_executor_simple.py
@@ -12,6 +12,7 @@
 import numpy as np
 
 import libensemble.sim_funcs.six_hump_camel as six_hump_camel
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
@@ -61,8 +62,12 @@
     # num sim_ended_count conditions in executor_hworld
     exit_criteria = {"sim_max": nworkers * 5}
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs)
 
     if is_manager:
         print("\nChecking expected task status against Workers ...\n")
diff --git a/libensemble/tests/functionality_tests/test_local_sine_tutorial.py b/libensemble/tests/functionality_tests/test_local_sine_tutorial.py
index e05a49c96..26a38b3e3 100644
--- a/libensemble/tests/functionality_tests/test_local_sine_tutorial.py
+++ b/libensemble/tests/functionality_tests/test_local_sine_tutorial.py
@@ -3,7 +3,8 @@
 from sine_sim import sim_find_sine
 
 from libensemble import Ensemble
-from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
+from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 
 if __name__ == "__main__":  # Python-quirk required on macOS and windows
     libE_specs = LibeSpecs(nworkers=4, comms="local")
@@ -27,6 +28,7 @@
     exit_criteria = ExitCriteria(sim_max=80)  # Stop libEnsemble after 80 simulations
 
     ensemble = Ensemble(sim_specs, gen_specs, exit_criteria, libE_specs)
+    ensemble.alloc_specs = AllocSpecs(alloc_f=give_sim_work_first)
     ensemble.add_random_streams()  # setup the random streams unique to each worker
     ensemble.run()  # start the ensemble. Blocks until completion.
 
diff --git a/libensemble/tests/functionality_tests/test_local_sine_tutorial_2.py b/libensemble/tests/functionality_tests/test_local_sine_tutorial_2.py
index 11911f343..75291ac44 100644
--- a/libensemble/tests/functionality_tests/test_local_sine_tutorial_2.py
+++ b/libensemble/tests/functionality_tests/test_local_sine_tutorial_2.py
@@ -3,7 +3,8 @@
 from sine_sim import sim_find_sine
 
 from libensemble import Ensemble
-from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
+from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 
 if __name__ == "__main__":
     libE_specs = LibeSpecs(nworkers=4, comms="local")
@@ -24,9 +25,11 @@
         out=[("y", float)],  # sim_f output. "y" = sine("x")
     )
 
+    alloc_specs = AllocSpecs(alloc_f=give_sim_work_first)
+
     exit_criteria = ExitCriteria(gen_max=160)
 
-    ensemble = Ensemble(sim_specs, gen_specs, exit_criteria, libE_specs)
+    ensemble = Ensemble(sim_specs, gen_specs, exit_criteria, libE_specs, alloc_specs)
     ensemble.add_random_streams()
     ensemble.run()
 
diff --git a/libensemble/tests/functionality_tests/test_local_sine_tutorial_3.py b/libensemble/tests/functionality_tests/test_local_sine_tutorial_3.py
index d57a0f842..6672feb9f 100644
--- a/libensemble/tests/functionality_tests/test_local_sine_tutorial_3.py
+++ b/libensemble/tests/functionality_tests/test_local_sine_tutorial_3.py
@@ -3,7 +3,8 @@
 from sine_sim import sim_find_sine
 
 from libensemble import Ensemble
-from libensemble.specs import ExitCriteria, GenSpecs, SimSpecs
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
+from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, SimSpecs
 
 if __name__ == "__main__":  # Python-quirk required on macOS and windows
     # libE_specs = LibeSpecs(nworkers=4, comms="local")
@@ -26,8 +27,10 @@
 
     exit_criteria = ExitCriteria(sim_max=80)  # Stop libEnsemble after 80 simulations
 
+    alloc_specs = AllocSpecs(alloc_f=give_sim_work_first)
+
     # replace libE_specs with parse_args=True. Detects MPI runtime
-    ensemble = Ensemble(sim_specs, gen_specs, exit_criteria, parse_args=True)
+    ensemble = Ensemble(sim_specs, gen_specs, exit_criteria, alloc_specs=alloc_specs, parse_args=True)
 
     ensemble.add_random_streams()
     ensemble.run()  # start the ensemble. Blocks until completion.
diff --git a/libensemble/tests/functionality_tests/test_mpi_runners.py b/libensemble/tests/functionality_tests/test_mpi_runners.py
index af00471d5..7c69e240c 100644
--- a/libensemble/tests/functionality_tests/test_mpi_runners.py
+++ b/libensemble/tests/functionality_tests/test_mpi_runners.py
@@ -12,6 +12,7 @@
 import numpy as np
 
 from libensemble import logger
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
@@ -233,8 +234,10 @@ def run_tests(mpi_runner, runner_name, test_list_exargs, exp_list):
             "tests": test_list,
         }
 
+        alloc_specs = {"alloc_f": give_sim_work_first}
+
         # Perform the run
-        H, pinfo, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+        H, pinfo, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs)
 
     # for run_set in ['mpich', 'openmpi', 'aprun', 'srun', 'jsrun', 'rename_mpich', 'custom']:
     for run_set in ["mpich", "aprun", "srun", "jsrun", "rename_mpich", "custom"]:
diff --git a/libensemble/tests/functionality_tests/test_mpi_runners_subnode.py b/libensemble/tests/functionality_tests/test_mpi_runners_subnode.py
index 7266678ff..223c4dfb3 100644
--- a/libensemble/tests/functionality_tests/test_mpi_runners_subnode.py
+++ b/libensemble/tests/functionality_tests/test_mpi_runners_subnode.py
@@ -16,6 +16,7 @@
 import numpy as np
 
 from libensemble import logger
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
@@ -91,6 +92,8 @@
         },
     }
 
+    alloc_specs = {"alloc_f": give_sim_work_first}
+
     persis_info = add_unique_random_streams({}, nworkers + 1)
     exit_criteria = {"sim_max": (nsim_workers) * rounds}
 
@@ -118,6 +121,6 @@
     }
 
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs)
 
     # All asserts are in sim func
diff --git a/libensemble/tests/functionality_tests/test_mpi_runners_subnode_uneven.py b/libensemble/tests/functionality_tests/test_mpi_runners_subnode_uneven.py
index a5145965b..941733996 100644
--- a/libensemble/tests/functionality_tests/test_mpi_runners_subnode_uneven.py
+++ b/libensemble/tests/functionality_tests/test_mpi_runners_subnode_uneven.py
@@ -14,6 +14,7 @@
 import numpy as np
 
 from libensemble import logger
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
@@ -92,6 +93,8 @@
         },
     }
 
+    alloc_specs = {"alloc_f": give_sim_work_first}
+
     persis_info = add_unique_random_streams({}, nworkers + 1)
     exit_criteria = {"sim_max": (nsim_workers) * rounds}
 
@@ -137,6 +140,6 @@
     }
 
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs)
 
     # All asserts are in sim func
diff --git a/libensemble/tests/functionality_tests/test_mpi_runners_supernode_uneven.py b/libensemble/tests/functionality_tests/test_mpi_runners_supernode_uneven.py
index 77975e200..329a2aa1b 100644
--- a/libensemble/tests/functionality_tests/test_mpi_runners_supernode_uneven.py
+++ b/libensemble/tests/functionality_tests/test_mpi_runners_supernode_uneven.py
@@ -11,6 +11,7 @@
 import numpy as np
 
 from libensemble import logger
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
@@ -131,7 +132,9 @@
         "expect": exp_list,
     }
 
+    alloc_specs = {"alloc_f": give_sim_work_first}
+
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs)
 
     # All asserts are in sim func
diff --git a/libensemble/tests/functionality_tests/test_mpi_runners_zrw_subnode_uneven.py b/libensemble/tests/functionality_tests/test_mpi_runners_zrw_subnode_uneven.py
index cc73d0e42..aa2a1a8eb 100644
--- a/libensemble/tests/functionality_tests/test_mpi_runners_zrw_subnode_uneven.py
+++ b/libensemble/tests/functionality_tests/test_mpi_runners_zrw_subnode_uneven.py
@@ -21,7 +21,6 @@
 import numpy as np
 
 from libensemble import logger
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.persistent_sampling import persistent_uniform as gen_f
 from libensemble.libE import libE
@@ -100,7 +99,6 @@
         },
     }
 
-    alloc_specs = {"alloc_f": alloc_f}
     exit_criteria = {"sim_max": (nsim_workers) * rounds}
 
     test_list_base = [
@@ -161,5 +159,5 @@
             persis_info = add_unique_random_streams({}, nworkers + 1)
 
         # Perform the run
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs)
+        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
         # Run-line asserts are in sim func
diff --git a/libensemble/tests/functionality_tests/test_mpi_runners_zrw_supernode_uneven.py b/libensemble/tests/functionality_tests/test_mpi_runners_zrw_supernode_uneven.py
index 640d613bf..f52aced21 100644
--- a/libensemble/tests/functionality_tests/test_mpi_runners_zrw_supernode_uneven.py
+++ b/libensemble/tests/functionality_tests/test_mpi_runners_zrw_supernode_uneven.py
@@ -11,7 +11,6 @@
 import numpy as np
 
 from libensemble import logger
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.executors.mpi_executor import MPIExecutor
 from libensemble.gen_funcs.persistent_sampling import persistent_uniform as gen_f
 from libensemble.libE import libE
@@ -86,7 +85,6 @@
         },
     }
 
-    alloc_specs = {"alloc_f": alloc_f}
     persis_info = add_unique_random_streams({}, nworkers + 1)
     exit_criteria = {"sim_max": (nsim_workers) * rounds}
 
@@ -139,6 +137,6 @@
     }
 
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
 
     # All asserts are in sim func
diff --git a/libensemble/tests/functionality_tests/test_mpi_warning.py b/libensemble/tests/functionality_tests/test_mpi_warning.py
index daf6125b6..ab7ac3664 100644
--- a/libensemble/tests/functionality_tests/test_mpi_warning.py
+++ b/libensemble/tests/functionality_tests/test_mpi_warning.py
@@ -17,11 +17,12 @@
 import numpy as np
 
 from libensemble import Ensemble, logger
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 
 # Import libEnsemble items for this test
 from libensemble.sim_funcs.simple_sim import norm_eval as sim_f
-from libensemble.specs import ExitCriteria, GenSpecs, SimSpecs
+from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, SimSpecs
 
 # Main block is necessary only when using local comms with spawn start method (default on macOS and Windows).
 if __name__ == "__main__":
@@ -41,6 +42,7 @@
             "ub": np.array([3, 2]),
         },
     )
+    sampling.alloc_specs = AllocSpecs(alloc_f=give_sim_work_first)
 
     sampling.exit_criteria = ExitCriteria(sim_max=100)
     sampling.add_random_streams()
diff --git a/libensemble/tests/functionality_tests/test_new_field.py b/libensemble/tests/functionality_tests/test_new_field.py
index c130b1d6e..bb7365c67 100644
--- a/libensemble/tests/functionality_tests/test_new_field.py
+++ b/libensemble/tests/functionality_tests/test_new_field.py
@@ -15,6 +15,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 
 # Import libEnsemble items for this test
@@ -48,11 +49,17 @@ def sim_f(In):
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1, seed=1234)
 
     exit_criteria = {"gen_max": 501}
 
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert len(H) >= 501
diff --git a/libensemble/tests/functionality_tests/test_persistent_uniform_sampling.py b/libensemble/tests/functionality_tests/test_persistent_uniform_sampling.py
index 81a18a528..50c9fd9ce 100644
--- a/libensemble/tests/functionality_tests/test_persistent_uniform_sampling.py
+++ b/libensemble/tests/functionality_tests/test_persistent_uniform_sampling.py
@@ -20,7 +20,6 @@
 
 import numpy as np
 
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.gen_funcs.persistent_sampling import batched_history_matching as gen_f2
 from libensemble.gen_funcs.persistent_sampling import persistent_uniform as gen_f1
 
@@ -56,8 +55,6 @@
         },
     }
 
-    alloc_specs = {"alloc_f": alloc_f}
-
     exit_criteria = {"gen_max": num_batches * batch, "wallclock_max": 300}
 
     libE_specs["kill_canceled_sims"] = False
@@ -93,7 +90,7 @@
             libE_specs["gen_workers"] = [2]
 
         # Perform the run
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs)
+        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
 
         if is_manager:
             assert len(np.unique(H["gen_ended_time"])) == num_batches
diff --git a/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_nonblocking.py b/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_nonblocking.py
index 542557884..c9e92a6c4 100644
--- a/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_nonblocking.py
+++ b/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_nonblocking.py
@@ -20,7 +20,6 @@
 
 import numpy as np
 
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.gen_funcs.persistent_sampling import uniform_nonblocking as gen_f
 
 # Import libEnsemble items for this test
@@ -53,8 +52,6 @@
         },
     }
 
-    alloc_specs = {"alloc_f": alloc_f}
-
     persis_info = add_unique_random_streams({}, nworkers + 1)
     for i in persis_info:
         persis_info[i]["get_grad"] = True
@@ -62,7 +59,7 @@
     exit_criteria = {"gen_max": 40, "wallclock_max": 300}
 
     # Perform the run
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs)
+    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
 
     if is_manager:
         assert len(np.unique(H["gen_ended_time"])) == 2
diff --git a/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_running_mean.py b/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_running_mean.py
index 9cc92dadd..9c915c82a 100644
--- a/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_running_mean.py
+++ b/libensemble/tests/functionality_tests/test_persistent_uniform_sampling_running_mean.py
@@ -20,7 +20,6 @@
 
 import numpy as np
 
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.gen_funcs.persistent_sampling import persistent_uniform_final_update as gen_f
 from libensemble.libE import libE
 from libensemble.sim_funcs.six_hump_camel import six_hump_camel_simple as sim_f
@@ -57,8 +56,6 @@
         },
     }
 
-    alloc_specs = {"alloc_f": alloc_f}
-
     sim_max = 120
     exit_criteria = {"sim_max": sim_max}
     libE_specs["final_gen_send"] = True
@@ -72,7 +69,7 @@
             }
 
         persis_info = add_unique_random_streams({}, nworkers + 1)
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs)
+        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
 
         if is_manager:
             # Check that last saved history agrees with returned history.
diff --git a/libensemble/tests/functionality_tests/test_sim_dirs_per_calc.py b/libensemble/tests/functionality_tests/test_sim_dirs_per_calc.py
index b4c30f9d2..9e1362b27 100644
--- a/libensemble/tests/functionality_tests/test_sim_dirs_per_calc.py
+++ b/libensemble/tests/functionality_tests/test_sim_dirs_per_calc.py
@@ -18,6 +18,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
 from libensemble.tests.regression_tests.support import write_sim_func as sim_f
@@ -61,11 +62,17 @@
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1)
 
     exit_criteria = {"sim_max": 21}
 
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert os.path.isdir(c_ensemble), f"Ensemble directory {c_ensemble} not created."
diff --git a/libensemble/tests/functionality_tests/test_sim_dirs_per_worker.py b/libensemble/tests/functionality_tests/test_sim_dirs_per_worker.py
index 69bb34ab8..249a3e9e1 100644
--- a/libensemble/tests/functionality_tests/test_sim_dirs_per_worker.py
+++ b/libensemble/tests/functionality_tests/test_sim_dirs_per_worker.py
@@ -18,6 +18,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
 from libensemble.tests.regression_tests.support import write_sim_func as sim_f
@@ -60,11 +61,17 @@
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1)
 
     exit_criteria = {"sim_max": 21}
 
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert os.path.isdir(w_ensemble), f"Ensemble directory {w_ensemble} not created."
diff --git a/libensemble/tests/functionality_tests/test_sim_dirs_with_exception.py b/libensemble/tests/functionality_tests/test_sim_dirs_with_exception.py
index 229f6d5f5..b3f951ab0 100644
--- a/libensemble/tests/functionality_tests/test_sim_dirs_with_exception.py
+++ b/libensemble/tests/functionality_tests/test_sim_dirs_with_exception.py
@@ -18,6 +18,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
 from libensemble.manager import LoggedException
@@ -53,13 +54,19 @@
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1)
 
     exit_criteria = {"sim_max": 21}
 
     return_flag = 1
     try:
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+        H, persis_info, flag = libE(
+            sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs
+        )
     except LoggedException as e:
         print(f"Caught deliberate exception: {e}")
         return_flag = 0
diff --git a/libensemble/tests/functionality_tests/test_sim_dirs_with_gen_dirs.py b/libensemble/tests/functionality_tests/test_sim_dirs_with_gen_dirs.py
index c73eeabad..cbf8d5244 100644
--- a/libensemble/tests/functionality_tests/test_sim_dirs_with_gen_dirs.py
+++ b/libensemble/tests/functionality_tests/test_sim_dirs_with_gen_dirs.py
@@ -18,6 +18,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.libE import libE
 from libensemble.tests.regression_tests.support import write_sim_func as sim_f
 from libensemble.tests.regression_tests.support import write_uniform_gen_func as gen_f
@@ -76,7 +77,13 @@
 
     exit_criteria = {"sim_max": 20}
 
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     def check_copied(type):
         input_copied = []
diff --git a/libensemble/tests/functionality_tests/test_sim_input_dir_option.py b/libensemble/tests/functionality_tests/test_sim_input_dir_option.py
index 7dc4da705..906d4d8c1 100644
--- a/libensemble/tests/functionality_tests/test_sim_input_dir_option.py
+++ b/libensemble/tests/functionality_tests/test_sim_input_dir_option.py
@@ -18,6 +18,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
 from libensemble.tests.regression_tests.support import write_sim_func as sim_f
@@ -60,7 +61,13 @@
 
     exit_criteria = {"sim_max": 21}
 
-    H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
+    H, persis_info, flag = libE(
+        sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+    )
 
     if is_manager:
         assert os.path.isdir(o_ensemble), f"Ensemble directory {o_ensemble} not created."
diff --git a/libensemble/tests/functionality_tests/test_uniform_sampling.py b/libensemble/tests/functionality_tests/test_uniform_sampling.py
index 2867f94df..ba327c684 100644
--- a/libensemble/tests/functionality_tests/test_uniform_sampling.py
+++ b/libensemble/tests/functionality_tests/test_uniform_sampling.py
@@ -19,6 +19,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample
 
 # Import libEnsemble items for this test
@@ -59,6 +60,10 @@
 
     exit_criteria = {"gen_max": 501, "wallclock_max": 300}
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     for run in range(2):
         if run == 1:
             # Test running a mock sim using previous history file
@@ -67,7 +72,9 @@
             sim_specs["user"] = {"history_file": hfile}
 
         # Perform the run
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+        H, persis_info, flag = libE(
+            sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs=libE_specs
+        )
 
         if is_manager:
             assert flag == 0
diff --git a/libensemble/tests/functionality_tests/test_worker_exceptions.py b/libensemble/tests/functionality_tests/test_worker_exceptions.py
index 435e621e1..88cb6fcb0 100644
--- a/libensemble/tests/functionality_tests/test_worker_exceptions.py
+++ b/libensemble/tests/functionality_tests/test_worker_exceptions.py
@@ -16,6 +16,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
 from libensemble.manager import LoggedException
@@ -52,10 +53,16 @@
     # Tell libEnsemble when to stop
     exit_criteria = {"wallclock_max": 10}
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     # Perform the run
     return_flag = 1
     try:
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+        H, persis_info, flag = libE(
+            sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+        )
     except LoggedException as e:
         print(f"Caught deliberate exception: {e}")
         return_flag = 0
diff --git a/libensemble/tests/functionality_tests/test_workflow_dir.py b/libensemble/tests/functionality_tests/test_workflow_dir.py
index 1abbc10bc..6c7550ac3 100644
--- a/libensemble/tests/functionality_tests/test_workflow_dir.py
+++ b/libensemble/tests/functionality_tests/test_workflow_dir.py
@@ -18,6 +18,7 @@
 
 import numpy as np
 
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import uniform_random_sample as gen_f
 from libensemble.libE import libE
 from libensemble.tests.regression_tests.support import write_sim_func as sim_f
@@ -58,6 +59,10 @@
         },
     }
 
+    alloc_specs = {
+        "alloc_f": give_sim_work_first,
+    }
+
     persis_info = add_unique_random_streams({}, nworkers + 1)
 
     exit_criteria = {"sim_max": 21}
@@ -70,7 +75,9 @@
             "./test_workflow" + str(i) + "_nworkers" + str(nworkers) + "_comms-" + libE_specs["comms"]
         )
 
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
+        H, persis_info, flag = libE(
+            sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs=alloc_specs, libE_specs=libE_specs
+        )
 
         assert os.path.isdir(libE_specs["workflow_dir_path"]), "workflow_dir not created"
         assert all(
diff --git a/libensemble/tests/regression_tests/test_1d_sampling.py b/libensemble/tests/regression_tests/test_1d_sampling.py
index edecabb66..7009a329b 100644
--- a/libensemble/tests/regression_tests/test_1d_sampling.py
+++ b/libensemble/tests/regression_tests/test_1d_sampling.py
@@ -16,7 +16,7 @@
 import numpy as np
 
 from libensemble import Ensemble
-from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
+from libensemble.gen_funcs.persistent_sampling import persistent_uniform
 
 # Import libEnsemble items for this test
 from libensemble.sim_funcs.simple_sim import norm_eval as sim_f
@@ -29,10 +29,10 @@
     sampling.libE_specs = LibeSpecs(save_every_k_gens=300, safe_mode=False, disable_log_files=True)
     sampling.sim_specs = SimSpecs(sim_f=sim_f)
     sampling.gen_specs = GenSpecs(
-        gen_f=gen_f,
+        gen_f=persistent_uniform,
         outputs=[("x", float, (1,))],
         user={
-            "gen_batch_size": 100,
+            "initial_batch_size": 100,
             "lb": np.array([-3]),
             "ub": np.array([3]),
         },
diff --git a/libensemble/tests/regression_tests/test_2d_sampling.py b/libensemble/tests/regression_tests/test_2d_sampling.py
index 8164c2844..a852a4a8b 100644
--- a/libensemble/tests/regression_tests/test_2d_sampling.py
+++ b/libensemble/tests/regression_tests/test_2d_sampling.py
@@ -16,11 +16,12 @@
 import numpy as np
 
 from libensemble import Ensemble
+from libensemble.alloc_funcs.give_sim_work_first import give_sim_work_first
 from libensemble.gen_funcs.sampling import latin_hypercube_sample as gen_f
 
 # Import libEnsemble items for this test
 from libensemble.sim_funcs.simple_sim import norm_eval as sim_f
-from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 
 # Main block is necessary only when using local comms with spawn start method (default on macOS and Windows).
 if __name__ == "__main__":
@@ -37,6 +38,8 @@
         },
     )
 
+    sampling.alloc_specs = AllocSpecs(alloc_f=give_sim_work_first)
+
     sampling.exit_criteria = ExitCriteria(sim_max=200)
     sampling.add_random_streams()
 
diff --git a/libensemble/tests/regression_tests/test_asktell_aposmm_nlopt.py b/libensemble/tests/regression_tests/test_asktell_aposmm_nlopt.py
index 83e3bf625..9aba020a2 100644
--- a/libensemble/tests/regression_tests/test_asktell_aposmm_nlopt.py
+++ b/libensemble/tests/regression_tests/test_asktell_aposmm_nlopt.py
@@ -34,9 +34,8 @@
 from gest_api.vocs import VOCS
 
 from libensemble import Ensemble
-from libensemble.alloc_funcs.persistent_aposmm_alloc import persistent_aposmm_alloc as alloc_f
 from libensemble.gen_classes import APOSMM
-from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, SimSpecs
+from libensemble.specs import ExitCriteria, GenSpecs, SimSpecs
 from libensemble.tests.regression_tests.support import six_hump_camel_minima as minima
 
 # Main block is necessary only when using local comms with spawn start method (default on macOS and Windows).
@@ -53,7 +52,6 @@
             sys.exit("Cannot run with a persistent worker if only one worker -- aborting...")
 
         n = 2
-        workflow.alloc_specs = AllocSpecs(alloc_f=alloc_f)
 
         vocs = VOCS(
             variables={"core": [-3, 3], "edge": [-2, 2], "core_on_cube": [-3, 3], "edge_on_cube": [-2, 2]},
diff --git a/libensemble/tests/regression_tests/test_asktell_gpCAM.py b/libensemble/tests/regression_tests/test_asktell_gpCAM.py
index b093a0df7..f59fc135d 100644
--- a/libensemble/tests/regression_tests/test_asktell_gpCAM.py
+++ b/libensemble/tests/regression_tests/test_asktell_gpCAM.py
@@ -24,7 +24,6 @@
 import numpy as np
 from gest_api.vocs import VOCS
 
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.gen_classes.gpCAM import GP_CAM, GP_CAM_Covar
 
 # Import libEnsemble items for this test
@@ -65,8 +64,6 @@
 
     vocs = VOCS(variables={"x0": [-3, 3], "x1": [-2, 2], "x2": [-1, 1], "x3": [-1, 1]}, objectives={"f": "MINIMIZE"})
 
-    alloc_specs = {"alloc_f": alloc_f}
-
     gen = GP_CAM_Covar(vocs)
 
     for inst in range(3):
@@ -89,7 +86,7 @@
             exit_criteria = {"sim_max": num_batches * batch_size, "wallclock_max": 300}
 
         # Perform the run
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, {}, alloc_specs, libE_specs)
+        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, {}, libE_specs=libE_specs)
         if is_manager:
             assert len(np.unique(H["gen_ended_time"])) == num_batches
 
diff --git a/libensemble/tests/regression_tests/test_gpCAM.py b/libensemble/tests/regression_tests/test_gpCAM.py
index 218ecfc91..b5074ac61 100644
--- a/libensemble/tests/regression_tests/test_gpCAM.py
+++ b/libensemble/tests/regression_tests/test_gpCAM.py
@@ -28,7 +28,6 @@
 
 import numpy as np
 
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.gen_funcs.persistent_gpCAM import persistent_gpCAM, persistent_gpCAM_covar
 
 # Import libEnsemble items for this test
@@ -67,8 +66,6 @@
         },
     }
 
-    alloc_specs = {"alloc_f": alloc_f}
-
     for inst in range(3):
         if inst == 0:
             gen_specs["gen_f"] = persistent_gpCAM_covar
@@ -91,7 +88,7 @@
         persis_info = add_unique_random_streams({}, nworkers + 1)
 
         # Perform the run
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs)
+        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
 
         if is_manager:
             assert len(np.unique(H["gen_ended_time"])) == num_batches
diff --git a/libensemble/tests/regression_tests/test_optimas_grid_sample.py b/libensemble/tests/regression_tests/test_optimas_grid_sample.py
index 57c6c8fed..c390be8ca 100644
--- a/libensemble/tests/regression_tests/test_optimas_grid_sample.py
+++ b/libensemble/tests/regression_tests/test_optimas_grid_sample.py
@@ -24,8 +24,7 @@
 from optimas.generators import GridSamplingGenerator
 
 from libensemble import Ensemble
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
-from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 
 
 def eval_func(input_params: dict):
@@ -73,13 +72,11 @@ def eval_func(input_params: dict):
         vocs=vocs,
     )
 
-    alloc_specs = AllocSpecs(alloc_f=alloc_f)
     exit_criteria = ExitCriteria(sim_max=n_evals)
 
     workflow = Ensemble(
         libE_specs=libE_specs,
         sim_specs=sim_specs,
-        alloc_specs=alloc_specs,
         gen_specs=gen_specs,
         exit_criteria=exit_criteria,
     )
diff --git a/libensemble/tests/regression_tests/test_persistent_tasmanian.py b/libensemble/tests/regression_tests/test_persistent_tasmanian.py
index 269c4ba59..c45adaca2 100644
--- a/libensemble/tests/regression_tests/test_persistent_tasmanian.py
+++ b/libensemble/tests/regression_tests/test_persistent_tasmanian.py
@@ -22,7 +22,6 @@
 
 import numpy as np
 
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
 from libensemble.gen_funcs.persistent_tasmanian import sparse_grid_batched as gen_f_batched
 
 # Import libEnsemble items for this test
@@ -74,8 +73,6 @@ def tasmanian_init_localp():
         "out": [("x", float, num_dimensions)],
     }
 
-    alloc_specs = {"alloc_f": alloc_f}
-
     grid_files = []
 
     for run in range(3):
@@ -116,7 +113,7 @@ def tasmanian_init_localp():
             gen_specs["user"]["sCriteria"] = "classic"
             gen_specs["user"]["iOutput"] = 0
 
-        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, alloc_specs, libE_specs)
+        H, persis_info, flag = libE(sim_specs, gen_specs, exit_criteria, persis_info, libE_specs=libE_specs)
 
         if is_manager:
             grid_files.append(gen_specs["user"]["tasmanian_checkpoint_file"])
diff --git a/libensemble/tests/regression_tests/test_xopt_EI.py b/libensemble/tests/regression_tests/test_xopt_EI.py
index bf114b38f..38a0cecd2 100644
--- a/libensemble/tests/regression_tests/test_xopt_EI.py
+++ b/libensemble/tests/regression_tests/test_xopt_EI.py
@@ -22,8 +22,7 @@
 from xopt.generators.bayesian.expected_improvement import ExpectedImprovementGenerator
 
 from libensemble import Ensemble
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
-from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 
 
 # Adapted from Xopt/xopt/resources/testing.py
@@ -83,13 +82,11 @@ def xtest_sim(H, persis_info, sim_specs, _):
         vocs=vocs,
     )
 
-    alloc_specs = AllocSpecs(alloc_f=alloc_f)
     exit_criteria = ExitCriteria(sim_max=20)
 
     workflow = Ensemble(
         libE_specs=libE_specs,
         sim_specs=sim_specs,
-        alloc_specs=alloc_specs,
         gen_specs=gen_specs,
         exit_criteria=exit_criteria,
     )
diff --git a/libensemble/tests/regression_tests/test_xopt_EI_xopt_sim.py b/libensemble/tests/regression_tests/test_xopt_EI_xopt_sim.py
index f2ff1453c..7d3ec5b87 100644
--- a/libensemble/tests/regression_tests/test_xopt_EI_xopt_sim.py
+++ b/libensemble/tests/regression_tests/test_xopt_EI_xopt_sim.py
@@ -22,8 +22,7 @@
 from xopt.generators.bayesian.expected_improvement import ExpectedImprovementGenerator
 
 from libensemble import Ensemble
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
-from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 
 
 # From Xopt/xopt/resources/testing.py
@@ -77,13 +76,11 @@ def xtest_callable(input_dict: dict, a=0) -> dict:
         vocs=vocs,
     )
 
-    alloc_specs = AllocSpecs(alloc_f=alloc_f)
     exit_criteria = ExitCriteria(sim_max=20)
 
     workflow = Ensemble(
         libE_specs=libE_specs,
         sim_specs=sim_specs,
-        alloc_specs=alloc_specs,
         gen_specs=gen_specs,
         exit_criteria=exit_criteria,
     )
diff --git a/libensemble/tests/regression_tests/test_xopt_nelder_mead.py b/libensemble/tests/regression_tests/test_xopt_nelder_mead.py
index 56e0daada..edefcd80e 100644
--- a/libensemble/tests/regression_tests/test_xopt_nelder_mead.py
+++ b/libensemble/tests/regression_tests/test_xopt_nelder_mead.py
@@ -20,8 +20,7 @@
 from xopt.generators.sequential.neldermead import NelderMeadGenerator
 
 from libensemble import Ensemble
-from libensemble.alloc_funcs.start_only_persistent import only_persistent_gens as alloc_f
-from libensemble.specs import AllocSpecs, ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
+from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
 
 
 def rosenbrock_callable(input_dict: dict) -> dict:
@@ -65,13 +64,11 @@ def rosenbrock_callable(input_dict: dict) -> dict:
         vocs=vocs,
     )
 
-    alloc_specs = AllocSpecs(alloc_f=alloc_f)
     exit_criteria = ExitCriteria(sim_max=30)
 
     workflow = Ensemble(
         libE_specs=libE_specs,
         sim_specs=sim_specs,
-        alloc_specs=alloc_specs,
         gen_specs=gen_specs,
         exit_criteria=exit_criteria,
     )
diff --git a/libensemble/tests/unit_tests/test_ensemble.py b/libensemble/tests/unit_tests/test_ensemble.py
index 271932573..501b14104 100644
--- a/libensemble/tests/unit_tests/test_ensemble.py
+++ b/libensemble/tests/unit_tests/test_ensemble.py
@@ -86,45 +86,6 @@ def test_bad_func_loads():
         assert flag == 0
 
 
-def test_full_workflow():
-    """Test initializing a workflow via Specs and Ensemble.run()"""
-    from libensemble.ensemble import Ensemble
-    from libensemble.gen_funcs.sampling import latin_hypercube_sample
-    from libensemble.sim_funcs.simple_sim import norm_eval
-    from libensemble.specs import ExitCriteria, GenSpecs, LibeSpecs, SimSpecs
-
-    LS = LibeSpecs(comms="local", nworkers=4)
-
-    # parameterizes and validates everything!
-    ens = Ensemble(
-        libE_specs=LS,
-        sim_specs=SimSpecs(sim_f=norm_eval),
-        gen_specs=GenSpecs(
-            gen_f=latin_hypercube_sample,
-            user={
-                "gen_batch_size": 100,
-                "lb": np.array([-3]),
-                "ub": np.array([3]),
-            },
-        ),
-        exit_criteria=ExitCriteria(gen_max=101),
-    )
-
-    ens.add_random_streams()
-    ens.run()
-    if ens.is_manager:
-        assert len(ens.H) >= 101
-
-    # test a dry run
-    ens.libE_specs.dry_run = True
-    flag = 1
-    try:
-        ens.run()
-    except SystemExit:
-        flag = 0
-    assert not flag, "Ensemble didn't exit after specifying dry_run"
-
-
 def test_flakey_workflow():
     """Test initializing a workflow via Specs and Ensemble.run()"""
     from pydantic import ValidationError
@@ -235,7 +196,6 @@ def test_local_comms_without_nworkers():
     test_ensemble_parse_args_false()
     test_from_files()
     test_bad_func_loads()
-    test_full_workflow()
     test_flakey_workflow()
     test_ensemble_specs_update_libE_specs()
     test_ensemble_prevent_comms_overwrite()