diff --git a/generators/ed25519.py b/generators/ed25519.py
index c947673..650c64d 100644
--- a/generators/ed25519.py
+++ b/generators/ed25519.py
@@ -1,6 +1,5 @@
 import fd58
 import hashlib
-from test_suite.codec_utils import encode_input
 import test_suite.invoke_pb2 as pb
 from dataclasses import dataclass
 import datetime
diff --git a/generators/secp256k1.py b/generators/secp256k1.py
index 341c5e2..f825762 100644
--- a/generators/secp256k1.py
+++ b/generators/secp256k1.py
@@ -1,7 +1,6 @@
 import fd58
 import hashlib
 from eth_hash.auto import keccak
-from test_suite.codec_utils import encode_input
 import test_suite.invoke_pb2 as pb
 from dataclasses import dataclass
 import datetime
diff --git a/invoke.proto b/invoke.proto
index de44ae8..9f3ba17 100644
--- a/invoke.proto
+++ b/invoke.proto
@@ -104,3 +104,35 @@ message InstrFixture {
   InstrContext input = 1;
   InstrEffects output = 2;
 }
+
+message ELFBinary {
+    bytes data = 1;
+}
+
+// Wrapper for the ELF binary and the features that the loader should use
+// Note that we currently hardcode the features to be used by the loader,
+// so features isn't actually used yet.
+message ELFLoaderCtx {
+    ELFBinary elf = 1;
+    FeatureSet features = 2;
+}
+
+// Captures the results of a elf binary load.
+// Structurally similar to fd_sbpf_program_t
+message ELFLoaderEffects {
+    bytes rodata = 1;
+    uint64 rodata_sz = 2;
+
+    // bytes text = 3; // not needed, just points to a region in rodata
+    uint64 text_cnt = 4;
+    uint64 text_off = 5;
+
+    uint64 entry_pc = 6;
+
+    repeated uint64 calldests = 7;
+}
+
+message ELFLoaderFixture {
+    ELFLoaderCtx input = 1;
+    ELFLoaderEffects output = 2;
+}
\ No newline at end of file
diff --git a/pyproject.toml b/pyproject.toml
index 6b8a588..2f7e504 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,5 +34,5 @@ dev = [
 ]
 
 [build-system]
-requires = ['setuptools']
+requires = ["setuptools", "setuptools_scm>=8"]
 build-backend = "setuptools.build_meta"
diff --git a/src/test_suite/debugger.py b/src/test_suite/debugger.py
index 5a2403a..629c127 100644
--- a/src/test_suite/debugger.py
+++ b/src/test_suite/debugger.py
@@ -6,8 +6,9 @@
 import os
 from test_suite.multiprocessing_utils import (
     initialize_process_output_buffers,
-    process_instruction,
+    process_target,
 )
+import test_suite.globals as globals
 
 
 def debug_target(shared_library, test_input, pipe):
@@ -23,7 +24,7 @@ def debug_target(shared_library, test_input, pipe):
 
     lib = ctypes.CDLL(shared_library)
     lib.sol_compat_init()
-    process_instruction(lib, test_input)
+    process_target(lib, test_input)
     lib.sol_compat_fini()
 
 
@@ -62,7 +63,7 @@ def debug_host(shared_library, instruction_context, gdb):
         # As soon as the target library gets loaded, set a breakpoint
         # for the newly appeared executor function
         "set breakpoint pending on",
-        "break sol_compat_instr_execute_v1",
+        f"break {globals.harness_ctx.fuzz_fn_name}",
         # GDB stops the process when attaching, let it continue
         "continue",
         # ... At this point, the child process has SIGSTOP'ed itself
diff --git a/src/test_suite/fixture_utils.py b/src/test_suite/fixture_utils.py
index 8b32221..3b1c226 100644
--- a/src/test_suite/fixture_utils.py
+++ b/src/test_suite/fixture_utils.py
@@ -1,9 +1,8 @@
 import fd58
-from test_suite.codec_utils import encode_input, encode_output
 from test_suite.constants import NATIVE_PROGRAM_MAPPING
 from test_suite.multiprocessing_utils import (
     build_test_results,
-    read_instr,
+    read_context,
     process_single_test_case,
     prune_execution_result,
 )
@@ -23,9 +22,10 @@ def create_fixture(test_file: Path) -> int:
     Returns:
         - int: 1 on success, 0 on failure
     """
-    serialized_instr_context = read_instr(test_file)
-    results = process_single_test_case(serialized_instr_context)
-    pruned_results = prune_execution_result(serialized_instr_context, results)
+    serialized_context = read_context(test_file)
+    results = process_single_test_case(serialized_context)
+
+    pruned_results = prune_execution_result(serialized_context, results)
 
     # This is only relevant when you gather results for multiple targets
     if globals.only_keep_passing:
@@ -38,25 +38,25 @@ def create_fixture(test_file: Path) -> int:
 
     serialized_instr_effects = pruned_results[globals.solana_shared_library]
 
-    if serialized_instr_context is None or serialized_instr_effects is None:
+    if serialized_context is None or serialized_instr_effects is None:
         return 0
 
     # Create instruction fixture
-    instr_context = pb.InstrContext()
-    instr_context.ParseFromString(serialized_instr_context)
-    instr_effects = pb.InstrEffects()
-    instr_effects.ParseFromString(serialized_instr_effects)
+    context = globals.harness_ctx.context_type()
+    context.ParseFromString(serialized_context)
+    effects = globals.harness_ctx.effects_type()
+    effects.ParseFromString(serialized_instr_effects)
 
-    fixture = pb.InstrFixture()
-    fixture.input.MergeFrom(instr_context)
-    fixture.output.MergeFrom(instr_effects)
+    fixture = globals.harness_ctx.fixture_type()
+    fixture.input.MergeFrom(context)
+    fixture.output.MergeFrom(effects)
 
     return write_fixture_to_disk(
         test_file.stem, fixture.SerializeToString(deterministic=True)
     )
 
 
-def write_fixture_to_disk(file_stem: str, serialized_instruction_fixture: str) -> int:
+def write_fixture_to_disk(file_stem: str, serialized_fixture: str) -> int:
     """
     Writes instruction fixtures to disk. This function outputs in binary format unless
     specified otherwise with the --readable flag.
@@ -67,47 +67,46 @@ def write_fixture_to_disk(file_stem: str, serialized_instruction_fixture: str) -
     Returns:
         - int: 0 on failure, 1 on success
     """
-    if serialized_instruction_fixture is None:
+    if serialized_fixture is None:
         return 0
 
     output_dir = globals.output_dir
 
     if globals.organize_fixture_dir:
-        instr_fixture = pb.InstrFixture()
-        instr_fixture.ParseFromString(serialized_instruction_fixture)
-        program_type = get_program_type(instr_fixture)
+        fixture = globals.harness_ctx.fixture_type()
+        fixture.ParseFromString(serialized_fixture)
+        program_type = get_program_type(fixture)
         output_dir = output_dir / program_type
         output_dir.mkdir(parents=True, exist_ok=True)
 
     if globals.readable:
         # Deserialize fixture
-        instr_fixture = pb.InstrFixture()
-        instr_fixture.ParseFromString(serialized_instruction_fixture)
+        fixture = pb.InstrFixture()
+        fixture.ParseFromString(serialized_fixture)
 
         # Encode fields for instruction context and effects
-        instr_context = pb.InstrContext()
-        instr_context.CopyFrom(instr_fixture.input)
-        encode_input(instr_context)
+        context = globals.harness_ctx.context_type()
+        context.CopyFrom(fixture.input)
+        # encode_input(context)
+        globals.harness_ctx.context_human_encode_fn(context)
 
-        instr_effects = pb.InstrEffects()
-        instr_effects.CopyFrom(instr_fixture.output)
-        encode_output(instr_effects)
+        instr_effects = globals.harness_ctx.effects_type()
+        instr_effects.CopyFrom(fixture.output)
+        globals.harness_ctx.effects_human_encode_fn(instr_effects)
 
-        instr_fixture.input.CopyFrom(instr_context)
-        instr_fixture.output.CopyFrom(instr_effects)
+        fixture.input.CopyFrom(context)
+        fixture.output.CopyFrom(instr_effects)
 
         with open(output_dir / (file_stem + ".fix.txt"), "w") as f:
-            f.write(
-                text_format.MessageToString(instr_fixture, print_unknown_fields=False)
-            )
+            f.write(text_format.MessageToString(fixture, print_unknown_fields=False))
     else:
         with open(output_dir / (file_stem + ".fix"), "wb") as f:
-            f.write(serialized_instruction_fixture)
+            f.write(serialized_fixture)
 
     return 1
 
 
-def extract_instr_context_from_fixture(fixture_file: Path):
+def extract_context_from_fixture(fixture_file: Path):
     """
     Extract InstrContext from InstrEffects and write to disk.
 
@@ -118,12 +117,12 @@ def extract_instr_context_from_fixture(fixture_file: Path):
         - int: 1 on success, 0 on failure
     """
     try:
-        instr_fixture = pb.InstrFixture()
+        fixture = globals.harness_ctx.fixture_type()
         with open(fixture_file, "rb") as f:
-            instr_fixture.ParseFromString(f.read())
+            fixture.ParseFromString(f.read())
 
         with open(globals.output_dir / (fixture_file.stem + ".bin"), "wb") as f:
-            f.write(instr_fixture.input.SerializeToString(deterministic=True))
+            f.write(fixture.input.SerializeToString(deterministic=True))
     except:
         return 0
 
diff --git a/src/test_suite/fuzz_context.py b/src/test_suite/fuzz_context.py
new file mode 100644
index 0000000..05f9188
--- /dev/null
+++ b/src/test_suite/fuzz_context.py
@@ -0,0 +1,16 @@
+from test_suite.fuzz_interface import HarnessCtx
+import test_suite.invoke_pb2 as pb
+import test_suite.instr.codec_utils as instr_codec
+
+
+ElfHarness = HarnessCtx(
+    fuzz_fn_name="sol_compat_elf_loader_v1", fixture_desc=pb.ELFLoaderFixture.DESCRIPTOR
+)
+
+InstrHarness = HarnessCtx(
+    fuzz_fn_name="sol_compat_instr_execute_v1",
+    fixture_desc=pb.InstrFixture.DESCRIPTOR,
+    context_human_encode_fn=instr_codec.encode_input,
+    context_human_decode_fn=instr_codec.decode_input,
+    effects_human_encode_fn=instr_codec.encode_output,
+)
diff --git a/src/test_suite/fuzz_interface.py b/src/test_suite/fuzz_interface.py
new file mode 100644
index 0000000..7d6d9bc
--- /dev/null
+++ b/src/test_suite/fuzz_interface.py
@@ -0,0 +1,59 @@
+from typing import Callable, Type, TypeVar
+from google.protobuf import message, descriptor, message_factory
+from dataclasses import dataclass, InitVar
+
+msg_factory = message_factory.MessageFactory()
+
+FixtureType = TypeVar("FixtureType", bound=message.Message)
+ContextType = TypeVar("ContextType", bound=message.Message)
+EffectsType = TypeVar("EffectsType", bound=message.Message)
+
+"""
+Each fuzzing harness should implement this interface in fuzz_context.py
+
+The following defines the interface:
+- fuzz_fn_name: The name of the harness function to call in the fuzz target
+- fixture_desc: The protobuf descriptor for the fixture message.
+    - A fixture message is a message that contains an input and output message.
+    - input: The fuzz target Context
+    - output: The fuzz target Effects
+- diff_effect_fn: A function that compares two effects messages for equality
+- human encode/decode functions for the context and effects messages to
+  convert the messages to/from human-readable format (in-place).
+  Both context and effects messages can have their own encode/decode functions.
+"""
+
+
+def generic_effects_diff(a: EffectsType, b: EffectsType) -> bool:
+    return a == b
+
+
+def generic_human_encode(obj: message.Message) -> None:
+    pass
+
+
+def generic_human_decode(obj: message.Message) -> None:
+    pass
+
+
+@dataclass
+class HarnessCtx:
+    fuzz_fn_name: str
+    fixture_desc: InitVar[descriptor.Descriptor]
+    diff_effect_fn: Callable[[EffectsType, EffectsType], bool] = generic_effects_diff
+    context_human_encode_fn: Callable[[ContextType], None] = generic_human_encode
+    context_human_decode_fn: Callable[[ContextType], None] = generic_human_decode
+    effects_human_encode_fn: Callable[[EffectsType], None] = generic_human_encode
+    effects_human_decode_fn: Callable[[EffectsType], None] = generic_human_decode
+    fixture_type: Type[FixtureType] = message.Message
+    context_type: Type[ContextType] = message.Message
+    effects_type: Type[EffectsType] = message.Message
+
+    def __post_init__(self, fixture_desc):
+        self.fixture_type = msg_factory.GetPrototype(fixture_desc)
+        self.context_type = msg_factory.GetPrototype(
+            fixture_desc.fields_by_name["input"].message_type
+        )
+        self.effects_type = msg_factory.GetPrototype(
+            fixture_desc.fields_by_name["output"].message_type
+        )
diff --git a/src/test_suite/globals.py b/src/test_suite/globals.py
index 587483c..f635615 100644
--- a/src/test_suite/globals.py
+++ b/src/test_suite/globals.py
@@ -1,10 +1,12 @@
+from test_suite.fuzz_interface import HarnessCtx
+
 # Global variables that can be accessed from processes.
 
 # Target libraries (for run-tests)
 target_libraries = {}
 
 # Ground truth library (for run-tests)
-solana_shared_library = None
+reference_shared_library = None
 
 # Number of iterations (for check-consistency)
 n_iterations = 0
@@ -27,3 +29,5 @@
 
 # (For fixtures) Whether to only keep passing tests
 only_keep_passing = False
+# Harness context
+harness_ctx: HarnessCtx = None
diff --git a/src/test_suite/codec_utils.py b/src/test_suite/instr/codec_utils.py
similarity index 100%
rename from src/test_suite/codec_utils.py
rename to src/test_suite/instr/codec_utils.py
diff --git a/src/test_suite/invoke_pb2.py b/src/test_suite/invoke_pb2.py
index 3ec7364..5cf4be0 100644
--- a/src/test_suite/invoke_pb2.py
+++ b/src/test_suite/invoke_pb2.py
@@ -19,7 +19,7 @@
   name='invoke.proto',
   package='org.solana.sealevel.v1',
   syntax='proto3',
-  serialized_pb=_b('\n\x0cinvoke.proto\x12\x16org.solana.sealevel.v1\"\x1e\n\nFeatureSet\x12\x10\n\x08\x66\x65\x61tures\x18\x01 \x03(\x06\"s\n\tAcctState\x12\x0f\n\x07\x61\x64\x64ress\x18\x01 \x01(\x0c\x12\x10\n\x08lamports\x18\x02 \x01(\x04\x12\x0c\n\x04\x64\x61ta\x18\x03 \x01(\x0c\x12\x12\n\nexecutable\x18\x04 \x01(\x08\x12\x12\n\nrent_epoch\x18\x05 \x01(\x04\x12\r\n\x05owner\x18\x06 \x01(\x0c\"D\n\x0c\x45pochContext\x12\x34\n\x08\x66\x65\x61tures\x18\x01 \x01(\x0b\x32\".org.solana.sealevel.v1.FeatureSet\"\r\n\x0bSlotContext\"\x0c\n\nTxnContext\"B\n\tInstrAcct\x12\r\n\x05index\x18\x01 \x01(\r\x12\x13\n\x0bis_writable\x18\x02 \x01(\x08\x12\x11\n\tis_signer\x18\x03 \x01(\x08\"\xf6\x02\n\x0cInstrContext\x12\x12\n\nprogram_id\x18\x01 \x01(\x0c\x12\x11\n\tloader_id\x18\x02 \x01(\x0c\x12\x33\n\x08\x61\x63\x63ounts\x18\x03 \x03(\x0b\x32!.org.solana.sealevel.v1.AcctState\x12\x39\n\x0einstr_accounts\x18\x04 \x03(\x0b\x32!.org.solana.sealevel.v1.InstrAcct\x12\x0c\n\x04\x64\x61ta\x18\x05 \x01(\x0c\x12\x10\n\x08\x63u_avail\x18\x06 \x01(\x04\x12\x37\n\x0btxn_context\x18\x07 \x01(\x0b\x32\".org.solana.sealevel.v1.TxnContext\x12\x39\n\x0cslot_context\x18\x08 \x01(\x0b\x32#.org.solana.sealevel.v1.SlotContext\x12;\n\repoch_context\x18\t \x01(\x0b\x32$.org.solana.sealevel.v1.EpochContext\"\x97\x01\n\x0cInstrEffects\x12\x0e\n\x06result\x18\x01 \x01(\x05\x12\x12\n\ncustom_err\x18\x02 \x01(\r\x12<\n\x11modified_accounts\x18\x03 \x03(\x0b\x32!.org.solana.sealevel.v1.AcctState\x12\x10\n\x08\x63u_avail\x18\x04 \x01(\x04\x12\x13\n\x0breturn_data\x18\x05 \x01(\x0c\"y\n\x0cInstrFixture\x12\x33\n\x05input\x18\x01 \x01(\x0b\x32$.org.solana.sealevel.v1.InstrContext\x12\x34\n\x06output\x18\x02 \x01(\x0b\x32$.org.solana.sealevel.v1.InstrEffectsb\x06proto3')
+  serialized_pb=_b('\n\x0cinvoke.proto\x12\x16org.solana.sealevel.v1\"\x1e\n\nFeatureSet\x12\x10\n\x08\x66\x65\x61tures\x18\x01 \x03(\x06\"s\n\tAcctState\x12\x0f\n\x07\x61\x64\x64ress\x18\x01 \x01(\x0c\x12\x10\n\x08lamports\x18\x02 \x01(\x04\x12\x0c\n\x04\x64\x61ta\x18\x03 \x01(\x0c\x12\x12\n\nexecutable\x18\x04 \x01(\x08\x12\x12\n\nrent_epoch\x18\x05 \x01(\x04\x12\r\n\x05owner\x18\x06 \x01(\x0c\"D\n\x0c\x45pochContext\x12\x34\n\x08\x66\x65\x61tures\x18\x01 \x01(\x0b\x32\".org.solana.sealevel.v1.FeatureSet\"\r\n\x0bSlotContext\"\x0c\n\nTxnContext\"B\n\tInstrAcct\x12\r\n\x05index\x18\x01 \x01(\r\x12\x13\n\x0bis_writable\x18\x02 \x01(\x08\x12\x11\n\tis_signer\x18\x03 \x01(\x08\"\xf6\x02\n\x0cInstrContext\x12\x12\n\nprogram_id\x18\x01 \x01(\x0c\x12\x11\n\tloader_id\x18\x02 \x01(\x0c\x12\x33\n\x08\x61\x63\x63ounts\x18\x03 \x03(\x0b\x32!.org.solana.sealevel.v1.AcctState\x12\x39\n\x0einstr_accounts\x18\x04 \x03(\x0b\x32!.org.solana.sealevel.v1.InstrAcct\x12\x0c\n\x04\x64\x61ta\x18\x05 \x01(\x0c\x12\x10\n\x08\x63u_avail\x18\x06 \x01(\x04\x12\x37\n\x0btxn_context\x18\x07 \x01(\x0b\x32\".org.solana.sealevel.v1.TxnContext\x12\x39\n\x0cslot_context\x18\x08 \x01(\x0b\x32#.org.solana.sealevel.v1.SlotContext\x12;\n\repoch_context\x18\t \x01(\x0b\x32$.org.solana.sealevel.v1.EpochContext\"\x97\x01\n\x0cInstrEffects\x12\x0e\n\x06result\x18\x01 \x01(\x05\x12\x12\n\ncustom_err\x18\x02 \x01(\r\x12<\n\x11modified_accounts\x18\x03 \x03(\x0b\x32!.org.solana.sealevel.v1.AcctState\x12\x10\n\x08\x63u_avail\x18\x04 \x01(\x04\x12\x13\n\x0breturn_data\x18\x05 \x01(\x0c\"y\n\x0cInstrFixture\x12\x33\n\x05input\x18\x01 \x01(\x0b\x32$.org.solana.sealevel.v1.InstrContext\x12\x34\n\x06output\x18\x02 \x01(\x0b\x32$.org.solana.sealevel.v1.InstrEffects\"\x19\n\tELFBinary\x12\x0c\n\x04\x64\x61ta\x18\x01 \x01(\x0c\"t\n\x0c\x45LFLoaderCtx\x12.\n\x03\x65lf\x18\x01 \x01(\x0b\x32!.org.solana.sealevel.v1.ELFBinary\x12\x34\n\x08\x66\x65\x61tures\x18\x02 \x01(\x0b\x32\".org.solana.sealevel.v1.FeatureSet\"~\n\x10\x45LFLoaderEffects\x12\x0e\n\x06rodata\x18\x01 \x01(\x0c\x12\x11\n\trodata_sz\x18\x02 \x01(\x04\x12\x10\n\x08text_cnt\x18\x04 \x01(\x04\x12\x10\n\x08text_off\x18\x05 \x01(\x04\x12\x10\n\x08\x65ntry_pc\x18\x06 \x01(\x04\x12\x11\n\tcalldests\x18\x07 \x03(\x04\"\x81\x01\n\x10\x45LFLoaderFixture\x12\x33\n\x05input\x18\x01 \x01(\x0b\x32$.org.solana.sealevel.v1.ELFLoaderCtx\x12\x38\n\x06output\x18\x02 \x01(\x0b\x32(.org.solana.sealevel.v1.ELFLoaderEffectsb\x06proto3')
 )
 
 
@@ -429,6 +429,179 @@
   serialized_end=1008,
 )
 
+
+_ELFBINARY = _descriptor.Descriptor(
+  name='ELFBinary',
+  full_name='org.solana.sealevel.v1.ELFBinary',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='data', full_name='org.solana.sealevel.v1.ELFBinary.data', index=0,
+      number=1, type=12, cpp_type=9, label=1,
+      has_default_value=False, default_value=_b(""),
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  syntax='proto3',
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=1010,
+  serialized_end=1035,
+)
+
+
+_ELFLOADERCTX = _descriptor.Descriptor(
+  name='ELFLoaderCtx',
+  full_name='org.solana.sealevel.v1.ELFLoaderCtx',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='elf', full_name='org.solana.sealevel.v1.ELFLoaderCtx.elf', index=0,
+      number=1, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='features', full_name='org.solana.sealevel.v1.ELFLoaderCtx.features', index=1,
+      number=2, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  syntax='proto3',
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=1037,
+  serialized_end=1153,
+)
+
+
+_ELFLOADEREFFECTS = _descriptor.Descriptor(
+  name='ELFLoaderEffects',
+  full_name='org.solana.sealevel.v1.ELFLoaderEffects',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='rodata', full_name='org.solana.sealevel.v1.ELFLoaderEffects.rodata', index=0,
+      number=1, type=12, cpp_type=9, label=1,
+      has_default_value=False, default_value=_b(""),
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='rodata_sz', full_name='org.solana.sealevel.v1.ELFLoaderEffects.rodata_sz', index=1,
+      number=2, type=4, cpp_type=4, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='text_cnt', full_name='org.solana.sealevel.v1.ELFLoaderEffects.text_cnt', index=2,
+      number=4, type=4, cpp_type=4, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='text_off', full_name='org.solana.sealevel.v1.ELFLoaderEffects.text_off', index=3,
+      number=5, type=4, cpp_type=4, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='entry_pc', full_name='org.solana.sealevel.v1.ELFLoaderEffects.entry_pc', index=4,
+      number=6, type=4, cpp_type=4, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='calldests', full_name='org.solana.sealevel.v1.ELFLoaderEffects.calldests', index=5,
+      number=7, type=4, cpp_type=4, label=3,
+      has_default_value=False, default_value=[],
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  syntax='proto3',
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=1155,
+  serialized_end=1281,
+)
+
+
+_ELFLOADERFIXTURE = _descriptor.Descriptor(
+  name='ELFLoaderFixture',
+  full_name='org.solana.sealevel.v1.ELFLoaderFixture',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='input', full_name='org.solana.sealevel.v1.ELFLoaderFixture.input', index=0,
+      number=1, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='output', full_name='org.solana.sealevel.v1.ELFLoaderFixture.output', index=1,
+      number=2, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None, file=DESCRIPTOR),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  syntax='proto3',
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=1284,
+  serialized_end=1413,
+)
+
 _EPOCHCONTEXT.fields_by_name['features'].message_type = _FEATURESET
 _INSTRCONTEXT.fields_by_name['accounts'].message_type = _ACCTSTATE
 _INSTRCONTEXT.fields_by_name['instr_accounts'].message_type = _INSTRACCT
@@ -438,6 +611,10 @@
 _INSTREFFECTS.fields_by_name['modified_accounts'].message_type = _ACCTSTATE
 _INSTRFIXTURE.fields_by_name['input'].message_type = _INSTRCONTEXT
 _INSTRFIXTURE.fields_by_name['output'].message_type = _INSTREFFECTS
+_ELFLOADERCTX.fields_by_name['elf'].message_type = _ELFBINARY
+_ELFLOADERCTX.fields_by_name['features'].message_type = _FEATURESET
+_ELFLOADERFIXTURE.fields_by_name['input'].message_type = _ELFLOADERCTX
+_ELFLOADERFIXTURE.fields_by_name['output'].message_type = _ELFLOADEREFFECTS
 DESCRIPTOR.message_types_by_name['FeatureSet'] = _FEATURESET
 DESCRIPTOR.message_types_by_name['AcctState'] = _ACCTSTATE
 DESCRIPTOR.message_types_by_name['EpochContext'] = _EPOCHCONTEXT
@@ -447,6 +624,10 @@
 DESCRIPTOR.message_types_by_name['InstrContext'] = _INSTRCONTEXT
 DESCRIPTOR.message_types_by_name['InstrEffects'] = _INSTREFFECTS
 DESCRIPTOR.message_types_by_name['InstrFixture'] = _INSTRFIXTURE
+DESCRIPTOR.message_types_by_name['ELFBinary'] = _ELFBINARY
+DESCRIPTOR.message_types_by_name['ELFLoaderCtx'] = _ELFLOADERCTX
+DESCRIPTOR.message_types_by_name['ELFLoaderEffects'] = _ELFLOADEREFFECTS
+DESCRIPTOR.message_types_by_name['ELFLoaderFixture'] = _ELFLOADERFIXTURE
 _sym_db.RegisterFileDescriptor(DESCRIPTOR)
 
 FeatureSet = _reflection.GeneratedProtocolMessageType('FeatureSet', (_message.Message,), dict(
@@ -512,5 +693,33 @@
   ))
 _sym_db.RegisterMessage(InstrFixture)
 
+ELFBinary = _reflection.GeneratedProtocolMessageType('ELFBinary', (_message.Message,), dict(
+  DESCRIPTOR = _ELFBINARY,
+  __module__ = 'invoke_pb2'
+  # @@protoc_insertion_point(class_scope:org.solana.sealevel.v1.ELFBinary)
+  ))
+_sym_db.RegisterMessage(ELFBinary)
+
+ELFLoaderCtx = _reflection.GeneratedProtocolMessageType('ELFLoaderCtx', (_message.Message,), dict(
+  DESCRIPTOR = _ELFLOADERCTX,
+  __module__ = 'invoke_pb2'
+  # @@protoc_insertion_point(class_scope:org.solana.sealevel.v1.ELFLoaderCtx)
+  ))
+_sym_db.RegisterMessage(ELFLoaderCtx)
+
+ELFLoaderEffects = _reflection.GeneratedProtocolMessageType('ELFLoaderEffects', (_message.Message,), dict(
+  DESCRIPTOR = _ELFLOADEREFFECTS,
+  __module__ = 'invoke_pb2'
+  # @@protoc_insertion_point(class_scope:org.solana.sealevel.v1.ELFLoaderEffects)
+  ))
+_sym_db.RegisterMessage(ELFLoaderEffects)
+
+ELFLoaderFixture = _reflection.GeneratedProtocolMessageType('ELFLoaderFixture', (_message.Message,), dict(
+  DESCRIPTOR = _ELFLOADERFIXTURE,
+  __module__ = 'invoke_pb2'
+  # @@protoc_insertion_point(class_scope:org.solana.sealevel.v1.ELFLoaderFixture)
+  ))
+_sym_db.RegisterMessage(ELFLoaderFixture)
+
 
 # @@protoc_insertion_point(module_scope)
diff --git a/src/test_suite/minimize_utils.py b/src/test_suite/minimize_utils.py
deleted file mode 100644
index bcc7cc3..0000000
--- a/src/test_suite/minimize_utils.py
+++ /dev/null
@@ -1,79 +0,0 @@
-from pathlib import Path
-import test_suite.invoke_pb2 as pb
-import test_suite.globals as globals
-from test_suite.multiprocessing_utils import (
-    read_instr,
-    process_instruction,
-)
-
-
-def minimize_single_test_case(test_file: Path) -> int:
-    """
-    Minimize a single test case by pruning any additional accounts / features that do not
-    affect output.
-
-    Args:
-        test_file (Path): The test file to minimize
-
-    Returns:
-        int: 0 on failure, 1 on success
-    """
-    _, serialized_instruction_context = read_instr(test_file)
-
-    # Skip if input is invalid
-    if serialized_instruction_context is None:
-        return 0
-
-    lib = globals.target_libraries[globals.solana_shared_library]
-
-    # Get a base output result (could be None)
-    baseline_instruction_effects = process_instruction(
-        lib, serialized_instruction_context
-    )
-
-    # Skip if input could not be processed
-    if baseline_instruction_effects is None:
-        return 0
-
-    # Serialize the instruction effects
-    serialized_baseline_instruction_effects = (
-        baseline_instruction_effects.SerializeToString(deterministic=True)
-    )
-
-    # Deserialize the instruction context
-    instruction_context = pb.InstrContext()
-    instruction_context.ParseFromString(serialized_instruction_context)
-
-    # Incrementally remove features and test the output
-    feature_count = len(instruction_context.epoch_context.features.features)
-    feature_idx = feature_count - 1
-    while feature_idx >= 0:
-        removed_feature = instruction_context.epoch_context.features.features[
-            feature_idx
-        ]
-        del instruction_context.epoch_context.features.features[feature_idx]
-        test_instruction_effects = process_instruction(
-            lib, instruction_context.SerializeToString(deterministic=True)
-        )
-        serialized_test_instruction_effects = (
-            test_instruction_effects.SerializeToString(deterministic=True)
-        )
-        if (
-            serialized_baseline_instruction_effects
-            != serialized_test_instruction_effects
-        ):
-            instruction_context.epoch_context.features.features.extend(
-                [removed_feature]
-            )
-        feature_idx -= 1
-
-    features = (
-        list(instruction_context.epoch_context.features.features)
-        + globals.feature_pool.hardcoded
-    )
-    del instruction_context.epoch_context.features.features[:]
-    instruction_context.epoch_context.features.features.extend(sorted(set(features)))
-
-    with open(globals.output_dir / (test_file.stem + ".txt"), "wb") as f:
-        f.write(instruction_context.SerializeToString(deterministic=True))
-    return 1
diff --git a/src/test_suite/multiprocessing_utils.py b/src/test_suite/multiprocessing_utils.py
index 4915966..f181523 100644
--- a/src/test_suite/multiprocessing_utils.py
+++ b/src/test_suite/multiprocessing_utils.py
@@ -1,7 +1,6 @@
 from dataclasses import dataclass, field
 from test_suite.constants import OUTPUT_BUFFER_SIZE
 import test_suite.invoke_pb2 as pb
-from test_suite.codec_utils import encode_input, encode_output, decode_input
 from test_suite.validation_utils import check_account_unchanged
 import ctypes
 from ctypes import c_uint64, c_int, POINTER, Structure
@@ -11,7 +10,7 @@
 import os
 
 
-def process_instruction(
+def process_target(
     library: ctypes.CDLL, serialized_instruction_context: str
 ) -> pb.InstrEffects | None:
     """
@@ -41,7 +40,8 @@ def process_instruction(
     out_sz = ctypes.c_uint64(OUTPUT_BUFFER_SIZE)
 
     # Call the function
-    result = library.sol_compat_instr_execute_v1(
+    sol_compat_fn = getattr(library, globals.harness_ctx.fuzz_fn_name)
+    result = sol_compat_fn(
         globals.output_buffer_pointer, ctypes.byref(out_sz), in_ptr, in_sz
     )
 
@@ -57,7 +57,7 @@ def process_instruction(
     return output_object
 
 
-def read_instr(test_file: Path) -> str | None:
+def read_context(test_file: Path) -> str | None:
     """
     Reads in test files and generates an InstrContext Protobuf object for a test case.
 
@@ -71,16 +71,19 @@ def read_instr(test_file: Path) -> str | None:
     try:
         # Read in binary Protobuf messages
         with open(test_file, "rb") as f:
-            instruction_context = pb.InstrContext()
+            instruction_context = globals.harness_ctx.context_type()
             instruction_context.ParseFromString(f.read())
     except:
         try:
             # Maybe it's in human-readable Protobuf format?
             with open(test_file) as f:
-                instruction_context = text_format.Parse(f.read(), pb.InstrContext())
+                instruction_context = text_format.Parse(
+                    f.read(), globals.harness_ctx.context_type()
+                )
 
             # Decode into digestable fields
-            decode_input(instruction_context)
+            # decode_input(instruction_context)
+            globals.harness_ctx.context_human_decode_fn(instruction_context)
         except:
             # Unable to read message, skip and continue
             instruction_context = None
@@ -112,7 +115,7 @@ def read_fixture(fixture_file: Path) -> str | None:
     try:
         # Read in binary Protobuf messages
         with open(fixture_file, "rb") as f:
-            instruction_fixture = pb.InstrFixture()
+            instruction_fixture = globals.harness_ctx.fixture_type()
             instruction_fixture.ParseFromString(f.read())
     except:
         # Unable to read message, skip and continue
@@ -139,16 +142,16 @@ def decode_single_test_case(test_file: Path) -> int:
     Returns:
         - int: 1 if successfully decoded and written, 0 if skipped.
     """
-    serialized_instruction_context = read_instr(test_file)
+    serialized_instruction_context = read_context(test_file)
 
     # Skip if input is invalid
     if serialized_instruction_context is None:
         return 0
 
     # Encode the input fields to be human readable
-    instruction_context = pb.InstrContext()
+    instruction_context = globals.harness_ctx.context_type()
     instruction_context.ParseFromString(serialized_instruction_context)
-    encode_input(instruction_context)
+    globals.harness_ctx.context_human_encode_fn(instruction_context)
 
     with open(globals.output_dir / (test_file.stem + ".txt"), "w") as f:
         f.write(
@@ -177,7 +180,7 @@ def process_single_test_case(
     # Execute test case on each target library
     results = {}
     for target in globals.target_libraries:
-        instruction_effects = process_instruction(
+        instruction_effects = process_target(
             globals.target_libraries[target], serialized_instruction_context
         )
         result = (
@@ -219,8 +222,8 @@ def merge_results_over_iterations(results: tuple) -> tuple[str, dict]:
 
 
 def prune_execution_result(
-    serialized_instruction_context: str,
-    targets_to_serialized_instruction_effects: dict[str, str | None],
+    serialized_context: str,
+    targets_to_serialized_effects: dict[str, str | None],
 ) -> dict[str, str | None] | None:
     """
     Prune execution result to only include actually modified accounts.
@@ -232,29 +235,36 @@ def prune_execution_result(
     Returns:
         - dict[str, str | None] | None: Serialized pruned instruction effects for each target.
     """
-    if serialized_instruction_context is None:
+    if serialized_context is None:
         return None
 
-    instruction_context = pb.InstrContext()
-    instruction_context.ParseFromString(serialized_instruction_context)
+    EffectsT = globals.harness_ctx.effects_type
+
+    if not hasattr(EffectsT(), "modified_accounts"):
+        # no execution results to prune
+        # TODO: perform this check in a more robust way
+        return targets_to_serialized_effects
+
+    context = globals.harness_ctx.context_type()
+    context.ParseFromString(serialized_context)
 
     targets_to_serialized_pruned_instruction_effects = {}
     for (
         target,
         serialized_instruction_effects,
-    ) in targets_to_serialized_instruction_effects.items():
+    ) in targets_to_serialized_effects.items():
         if serialized_instruction_effects is None:
             targets_to_serialized_pruned_instruction_effects[target] = None
             continue
 
-        instruction_effects = pb.InstrEffects()
+        instruction_effects = EffectsT()
         instruction_effects.ParseFromString(serialized_instruction_effects)
 
         # O(n^2) because not performance sensitive
         new_modified_accounts: list[pb.AcctState] = []
         for modified_account in instruction_effects.modified_accounts:
             account_unchanged = False
-            for beginning_account_state in instruction_context.accounts:
+            for beginning_account_state in context.accounts:
                 account_unchanged |= check_account_unchanged(
                     modified_account, beginning_account_state
                 )
@@ -294,9 +304,9 @@ def check_consistency_in_results(file_stem: str, results: dict) -> dict[str, boo
             protobuf_struct = None
             if results[target][iteration]:
                 # Turn bytes into human readable fields
-                protobuf_struct = pb.InstrEffects()
+                protobuf_struct = globals.harness_ctx.effects_type()
                 protobuf_struct.ParseFromString(results[target][iteration])
-                encode_output(protobuf_struct)
+                globals.harness_ctx.effects_human_encode_fn(protobuf_struct)
 
             protobuf_structures[iteration] = protobuf_struct
 
@@ -348,9 +358,9 @@ def build_test_results(results: dict[str, str | None]) -> tuple[int, dict | None
         instruction_effects = None
         if result:
             # Turn bytes into human readable fields
-            instruction_effects = pb.InstrEffects()
+            instruction_effects = globals.harness_ctx.effects_type()
             instruction_effects.ParseFromString(result)
-            encode_output(instruction_effects)
+            globals.harness_ctx.effects_human_encode_fn(instruction_effects)
             outputs[target] = text_format.MessageToString(instruction_effects)
 
         protobuf_structures[target] = instruction_effects
@@ -428,12 +438,11 @@ def run_test(test_file: Path) -> tuple[str, int, dict | None]:
     """
     # Process fixtures through this entrypoint as well
     if test_file.suffix == ".fix":
-        fixture = pb.InstrFixture()
-        serialized_fixture = read_fixture(test_file)
-        fixture.MergeFromString(serialized_fixture)
+        fixture = globals.harness_ctx.fixture_type()
+        fixture.ParseFromString(test_file.open("rb").read())
         serialized_instr_context = fixture.input.SerializeToString(deterministic=True)
     else:
-        serialized_instr_context = read_instr(test_file)
+        serialized_instr_context = read_context(test_file)
     results = process_single_test_case(serialized_instr_context)
     pruned_results = prune_execution_result(serialized_instr_context, results)
     return test_file.stem, *build_test_results(pruned_results)
diff --git a/src/test_suite/test_suite.py b/src/test_suite/test_suite.py
index bbfd116..1c2962b 100644
--- a/src/test_suite/test_suite.py
+++ b/src/test_suite/test_suite.py
@@ -9,16 +9,15 @@
 from test_suite.constants import LOG_FILE_SEPARATOR_LENGTH, NATIVE_PROGRAM_MAPPING
 from test_suite.fixture_utils import (
     create_fixture,
-    extract_instr_context_from_fixture,
+    extract_context_from_fixture,
 )
 import test_suite.invoke_pb2 as pb
-from test_suite.codec_utils import encode_output
-from test_suite.minimize_utils import minimize_single_test_case
+from test_suite.instr.codec_utils import encode_output
 from test_suite.multiprocessing_utils import (
     decode_single_test_case,
-    read_instr,
+    read_context,
     initialize_process_output_buffers,
-    process_instruction,
+    process_target,
     prune_execution_result,
     get_feature_pool,
     run_test,
@@ -27,6 +26,9 @@
 from test_suite.debugger import debug_host
 import resource
 import tqdm
+from test_suite.fuzz_context import ElfHarness, InstrHarness
+
+globals.harness_ctx = InstrHarness
 
 
 app = typer.Typer(
@@ -36,7 +38,12 @@
 
 @app.command()
 def exec_instr(
-    file: Path = typer.Option(None, "--input", "-i", help="Input file"),
+    file: Path = typer.Option(
+        None,
+        "--input",
+        "-i",
+        help=f"Input {globals.harness_ctx.context_type.__name__} file",
+    ),
     shared_library: Path = typer.Option(
         Path("impl/firedancer/build/native/clang/lib/libfd_exec_sol_compat.so"),
         "--target",
@@ -50,8 +57,8 @@ def exec_instr(
         help="Randomizes bytes in output buffer before shared library execution",
     ),
 ):
-    instruction_context = read_instr(file)
-    assert instruction_context is not None, f"Unable to read {file.name}"
+    context = read_context(file)
+    assert context is not None, f"Unable to read {file.name}"
 
     # Initialize output buffers and shared library
     initialize_process_output_buffers(randomize_output_buffer=randomize_output_buffer)
@@ -59,29 +66,28 @@ def exec_instr(
     lib.sol_compat_init()
 
     # Execute and cleanup
-    instruction_effects = process_instruction(lib, instruction_context)
+    effects = process_target(lib, context)
 
-    if not instruction_effects:
+    if not effects:
         print("No instruction effects returned")
         return None
 
-    instruction_effects = instruction_effects.SerializeToString(deterministic=True)
+    serialized_effects = effects.SerializeToString(deterministic=True)
 
     # Prune execution results
-    pruned_instruction_effects = prune_execution_result(
-        instruction_context,
-        {shared_library: instruction_effects},
-    )
-    parsed_instruction_effects = pb.InstrEffects()
-    parsed_instruction_effects.ParseFromString(
-        pruned_instruction_effects[shared_library]
-    )
+    serialized_effects = prune_execution_result(
+        context,
+        {shared_library: serialized_effects},
+    )[shared_library]
+
+    parsed_instruction_effects = globals.harness_ctx.effects_type()
+    parsed_instruction_effects.ParseFromString(serialized_effects)
 
     lib.sol_compat_fini()
 
     # Print human-readable output
     if parsed_instruction_effects:
-        encode_output(parsed_instruction_effects)
+        globals.harness_ctx.effects_human_encode_fn(parsed_instruction_effects)
 
     print(parsed_instruction_effects)
 
@@ -103,82 +109,24 @@ def debug_instr(
     print(f"Processing {file.name}...")
 
     # Decode the file and pass it into GDB
-    instruction_context = read_instr(file)
+    instruction_context = read_context(file)
     assert instruction_context is not None, f"Unable to read {file.name}"
     debug_host(shared_library, instruction_context, gdb=debugger)
 
 
-@app.command()
-def minimize_tests(
-    input_dir: Path = typer.Option(
-        Path("corpus8"),
-        "--input-dir",
-        "-i",
-        help="Input directory containing instruction context messages",
-    ),
-    solana_shared_library: Path = typer.Option(
-        Path("impl/lib/libsolfuzz_agave_v2.0.so"),
-        "--solana-target",
-        "-s",
-        help="Solana (or ground truth) shared object (.so) target file path",
-    ),
-    output_dir: Path = typer.Option(
-        Path("test_results"),
-        "--output-dir",
-        "-o",
-        help="Output directory for test results",
-    ),
-    num_processes: int = typer.Option(
-        4, "--num-processes", "-p", help="Number of processes to use"
-    ),
-):
-    # Specify globals
-    globals.output_dir = output_dir
-    globals.solana_shared_library = solana_shared_library
-
-    # Create the output directory, if necessary
-    if globals.output_dir.exists():
-        shutil.rmtree(globals.output_dir)
-    globals.output_dir.mkdir(parents=True, exist_ok=True)
-
-    # Load in and initialize shared library
-    lib = ctypes.CDLL(globals.solana_shared_library)
-    lib.sol_compat_init()
-    globals.target_libraries[globals.solana_shared_library] = lib
-
-    globals.feature_pool = get_feature_pool(lib)
-
-    num_test_cases = len(list(input_dir.iterdir()))
-
-    minimize_results = []
-    with Pool(
-        processes=num_processes, initializer=initialize_process_output_buffers
-    ) as pool:
-        for result in tqdm.tqdm(
-            pool.imap(minimize_single_test_case, input_dir.iterdir()),
-            total=num_test_cases,
-        ):
-            minimize_results.append(result)
-
-    lib.sol_compat_fini()
-    print("-" * LOG_FILE_SEPARATOR_LENGTH)
-    print(f"{len(minimize_results)} total files seen")
-    print(f"{sum(minimize_results)} files successfully minimized")
-
-
 @app.command()
 def instr_from_fixtures(
     input_dir: Path = typer.Option(
         Path("fixtures"),
         "--input-dir",
         "-i",
-        help="Input directory containing instruction fixture messages",
+        help=f"Input directory containing {globals.harness_ctx.fixture_type.__name__} messages",
     ),
     output_dir: Path = typer.Option(
         Path("instr"),
         "--output-dir",
         "-o",
-        help="Output directory for instr contexts",
+        help=f"Output directory for {globals.harness_ctx.context_type.__name__} messages",
     ),
     num_processes: int = typer.Option(
         4, "--num-processes", "-p", help="Number of processes to use"
@@ -195,11 +143,11 @@ def instr_from_fixtures(
     test_cases = list(input_dir.iterdir())
     num_test_cases = len(test_cases)
 
-    print("Converting to InstrContext...")
+    print(f"Converting to {globals.harness_ctx.context_type.__name__}...")
     results = []
     with Pool(processes=num_processes) as pool:
         for result in tqdm.tqdm(
-            pool.imap(extract_instr_context_from_fixture, test_cases),
+            pool.imap(extract_context_from_fixture, test_cases),
             total=num_test_cases,
         ):
             results.append(result)
@@ -215,7 +163,7 @@ def create_fixtures(
         Path("corpus8"),
         "--input-dir",
         "-i",
-        help="Input directory containing instruction context messages",
+        help=f"Input directory containing {globals.harness_ctx.context_type.__name__} messages",
     ),
     solana_shared_library: Path = typer.Option(
         Path("impl/lib/libsolfuzz_agave_v2.0.so"),
@@ -227,7 +175,8 @@ def create_fixtures(
         [],
         "--target",
         "-t",
-        help="Shared object (.so) target file paths (pairs with --keep-passing)",
+        help="Shared object (.so) target file paths (pairs with --keep-passing)."
+        f" Targets must have {globals.harness_ctx.fuzz_fn_name} defined",
     ),
     output_dir: Path = typer.Option(
         Path("test_fixtures"),
@@ -304,7 +253,8 @@ def run_tests(
         Path("corpus8"),
         "--input-dir",
         "-i",
-        help="Input directory containing instruction context or fixture messages",
+        help=f"Input directory containing {globals.harness_ctx.context_type.__name__}"
+        f" or { globals.harness_ctx.fixture_type.__name__ } messages",
     ),
     solana_shared_library: Path = typer.Option(
         Path("impl/lib/libsolfuzz_agave_v2.0.so"),
@@ -435,13 +385,13 @@ def decode_protobuf(
         Path("raw_instruction_context"),
         "--input-dir",
         "-i",
-        help="Input directory containing instruction context messages in binary format",
+        help=f"Input directory containing {globals.harness_ctx.context_type.__name__} messages",
     ),
     output_dir: Path = typer.Option(
         Path("readable_instruction_context"),
         "--output-dir",
         "-o",
-        help="Output directory for base58-encoded, human-readable instruction context messages",
+        help=f"Output directory for base58-encoded, human-readable {globals.harness_ctx.context_type.__name__} messages",
     ),
     num_processes: int = typer.Option(
         4, "--num-processes", "-p", help="Number of processes to use"