diff --git a/Ix/Aggr/FunctionGroups.lean b/Ix/Aggr/FunctionGroups.lean
index 24c594e7a..0cc45eacd 100644
--- a/Ix/Aggr/FunctionGroups.lean
+++ b/Ix/Aggr/FunctionGroups.lean
@@ -13,7 +13,227 @@ public section
 
 namespace Aggr
 
-def functionGroups : Array (String × Array String) := #[]
+-- 21 groups over 174 circuits, cost-aware greedy merging
+-- over the ix_aggr join and two standalone-verifier profiles (average 2%,
+-- max 4% modelled cost increase per workload).
+def functionGroups : Array (String × Array String) := #[
+  ("aggr_group_00", #[
+    "memo_u32_less_than",
+    "u64_is_zero",
+    "relaxed_u64_succ",
+    "flatten_u64",
+    "read_sys_lookups_n",
+    "frontier_merge",
+    "frontier_split",
+    "frontier_sort",
+    "frontier_leaves",
+    "rows_at_round",
+    "limbs_onto",
+    "from_ext_basis"
+  ]),
+  ("aggr_group_01", #[
+    "address_eq_tail",
+    "address_eq",
+    "aggr_address_order",
+    "aggr_load_canonical_tree",
+    "aggr_assert_same_list",
+    "aggr_assert_union",
+    "aggr_parse_check_env",
+    "aggr_load_preimage",
+    "aggr_claim_digest",
+    "aggr_assert_digest",
+    "aggr_only_claim",
+    "aggr_child_check_env_digest"
+  ]),
+  ("aggr_group_02", #[
+    "read_u8",
+    "read_digest_vec_at",
+    "read_vk_u32_limb",
+    "read_field",
+    "lookup_groups_count",
+    "assert_blowup_zero",
+    "last_acc_is_zero",
+    "ext_exp_pow2",
+    "reconstruct_ext_row",
+    "assert_bits",
+    "select_active_circuits",
+    "select_active_prep",
+    "list_length.SysCircuit"
+  ]),
+  ("aggr_group_03", #[
+    "read_u64",
+    "blake3_next_layer",
+    "blake3_compress_layer",
+    "read_vk_u64",
+    "mmcs_verify_multi",
+    "pcs_check_witness",
+    "open_prep_batch",
+    "query_loop",
+    "verify_commit_multi",
+    "ch_sample_field",
+    "ch_sample_ext",
+    "snoc_b8",
+    "logup_steps_fold"
+  ]),
+  ("aggr_group_04", #[
+    "read_count",
+    "read_opened_round",
+    "read_batch_opening_vec_n",
+    "read_commit_phase_step_vec_n",
+    "read_preprocessed",
+    "bytes_to_addr",
+    "mmcs_compress",
+    "pcs_betas",
+    "verify_query",
+    "cap_onto",
+    "ch_sample_bits",
+    "fingerprint_vals",
+    "read_claim_vals_n",
+    "list_length.Bucket",
+    "list_concat.U8_8"
+  ]),
+  ("aggr_group_05", #[
+    "read_count_at",
+    "list_drop.SysNode"
+  ]),
+  ("aggr_group_06", #[
+    "read_active_n",
+    "read_u64_vec_vec_vec_n",
+    "read_opened_round_n",
+    "b3_w4_onto",
+    "frontier_fold",
+    "circ_has_height",
+    "heights_all",
+    "heights_prep",
+    "batch_views_at",
+    "step_views_at",
+    "drop_index_bits",
+    "take_bits"
+  ]),
+  ("aggr_group_07", #[
+    "read_u64_vec",
+    "list_length.Ptr.U8_8_4"
+  ]),
+  ("aggr_group_08", #[
+    "read_ext_vec",
+    "read_ext_vec_vec",
+    "read_ext_vec_vec_n",
+    "pad_block",
+    "read_vk_u16_limb",
+    "has_height",
+    "bits_to_num",
+    "exp_by_bits",
+    "points_onto",
+    "round_onto",
+    "log_degrees_onto",
+    "list_concat.Ptr.U8_32"
+  ]),
+  ("aggr_group_09", #[
+    "read_ext_vec_n",
+    "pair_mul"
+  ]),
+  ("aggr_group_10", #[
+    "read_digest_vec_at_n",
+    "read_merkle_cap_vec_n",
+    "read_opt_idx_n",
+    "leaf_hash_at",
+    "fri_fold2",
+    "obs_log_arities",
+    "build_buckets",
+    "rollin",
+    "sample_query_indices",
+    "query_views",
+    "snoc_cap",
+    "two_adic_gen",
+    "pow2",
+    "quotient_eval",
+    "list_length.CommitPhaseMultiStep"
+  ]),
+  ("aggr_group_11", #[
+    "read_u64_vec_vec_n",
+    "read_node_ids_n"
+  ]),
+  ("aggr_group_12", #[
+    "bytes_to_block",
+    "blake3_finish",
+    "blake3_compress_block",
+    "read_sys_circuits_n",
+    "ch_sample8",
+    "ood_loop",
+    "aggr_read_address",
+    "aggr_put_address"
+  ]),
+  ("aggr_group_13", #[
+    "read_vk_cap_n",
+    "read_opt_commit",
+    "prep_count",
+    "heights_max",
+    "verify_one_query",
+    "verify_input_multi",
+    "quotient_degree_of",
+    "claims_acc",
+    "read_claims_n",
+    "aggr_pack_address",
+    "list_length.FrontierNode"
+  ]),
+  ("aggr_group_14", #[
+    "compress_ordered",
+    "ood_fold",
+    "list_is_empty.Ptr.U8_32"
+  ]),
+  ("aggr_group_15", #[
+    "select_rows_le",
+    "frontier_level",
+    "accs_onto"
+  ]),
+  ("aggr_group_16", #[
+    "inject_maybe",
+    "rev_onto",
+    "list_lookup.G_2",
+    "list_drop.G_2"
+  ]),
+  ("aggr_group_17", #[
+    "open_2pt_mat",
+    "open_batch_2pt",
+    "open_quotient",
+    "open_prep",
+    "fold_roots",
+    "logup_fingerprint"
+  ]),
+  ("aggr_group_18", #[
+    "aggr_node_hash",
+    "aggr_leaf_hash",
+    "aggr_assert_strict_sorted",
+    "aggr_parse_tree_body",
+    "aggr_leaf_hashes",
+    "aggr_pair_hashes",
+    "aggr_reduce_hashes",
+    "aggr_canonical_root",
+    "aggr_load_optional_tree",
+    "aggr_next_assumption",
+    "aggr_seek_subject",
+    "aggr_assert_difference",
+    "aggr_get_opt_address",
+    "aggr_claim_field",
+    "list_lookup.U8_8",
+    "list_drop.U8_8"
+  ]),
+  ("aggr_group_19", #[
+    "aggr_fold_path",
+    "aggr_discharge_choice",
+    "aggr_assert_structural_difference",
+    "aggr_load_sys",
+    "aggr_verify_child",
+    "aggr_wrap",
+    "aggr_pair",
+    "aggr_pair_structural"
+  ]),
+  ("aggr_group_20", #[
+    "list_lookup.BatchOpening",
+    "list_length.CommitPhaseProofStep",
+    "list_drop.G"
+  ])
+]
 
 end Aggr
 
diff --git a/Ix/MultiStark/VerifierFunctionGroups.lean b/Ix/MultiStark/VerifierFunctionGroups.lean
index 5c9c8501a..0615126b1 100644
--- a/Ix/MultiStark/VerifierFunctionGroups.lean
+++ b/Ix/MultiStark/VerifierFunctionGroups.lean
@@ -13,7 +13,190 @@ public section
 
 namespace MultiStark
 
-def verifierFunctionGroups : Array (String × Array String) := #[]
+-- 20 groups over 139 circuits, cost-aware greedy merging
+-- over the ix_aggr join and two standalone-verifier profiles (average 2%,
+-- max 4% modelled cost increase per workload).
+def verifierFunctionGroups : Array (String × Array String) := #[
+  ("verifier_group_00", #[
+    "memo_u32_less_than",
+    "u64_is_zero",
+    "relaxed_u64_succ",
+    "flatten_u64",
+    "read_sys_lookups_n",
+    "frontier_merge",
+    "frontier_split",
+    "frontier_sort",
+    "frontier_leaves",
+    "rows_at_round",
+    "limbs_onto",
+    "from_ext_basis"
+  ]),
+  ("verifier_group_01", #[
+    "address_eq_tail",
+    "address_eq"
+  ]),
+  ("verifier_group_02", #[
+    "read_u8",
+    "read_digest_vec_at",
+    "read_vk_u32_limb",
+    "read_field",
+    "lookup_groups_count",
+    "assert_blowup_zero",
+    "last_acc_is_zero",
+    "ext_exp_pow2",
+    "reconstruct_ext_row",
+    "assert_bits",
+    "select_active_circuits",
+    "select_active_prep",
+    "list_length.SysCircuit"
+  ]),
+  ("verifier_group_03", #[
+    "read_u64",
+    "blake3_next_layer",
+    "blake3_compress_layer",
+    "read_vk_u64",
+    "mmcs_verify_multi",
+    "pcs_check_witness",
+    "open_prep_batch",
+    "query_loop",
+    "verify_commit_multi",
+    "ch_sample_field",
+    "ch_sample_ext",
+    "snoc_b8",
+    "logup_steps_fold"
+  ]),
+  ("verifier_group_04", #[
+    "read_count",
+    "read_opened_round",
+    "read_batch_opening_vec_n",
+    "read_commit_phase_step_vec_n",
+    "read_preprocessed",
+    "bytes_to_addr",
+    "mmcs_compress",
+    "pcs_betas",
+    "verify_query",
+    "cap_onto",
+    "ch_sample_bits",
+    "fingerprint_vals",
+    "read_claim_vals_n",
+    "list_length.Bucket",
+    "list_concat.U8_8"
+  ]),
+  ("verifier_group_05", #[
+    "read_count_at",
+    "list_drop.SysNode"
+  ]),
+  ("verifier_group_06", #[
+    "read_active_n",
+    "read_u64_vec_vec_vec_n",
+    "read_opened_round_n",
+    "b3_w4_onto",
+    "frontier_fold",
+    "circ_has_height",
+    "heights_all",
+    "heights_prep",
+    "batch_views_at",
+    "step_views_at",
+    "drop_index_bits",
+    "take_bits"
+  ]),
+  ("verifier_group_07", #[
+    "read_u64_vec",
+    "list_length.Ptr.U8_8_4"
+  ]),
+  ("verifier_group_08", #[
+    "read_ext_vec",
+    "read_ext_vec_vec",
+    "read_ext_vec_vec_n",
+    "pad_block",
+    "read_vk_u16_limb",
+    "has_height",
+    "bits_to_num",
+    "exp_by_bits",
+    "points_onto",
+    "round_onto",
+    "log_degrees_onto",
+    "list_concat.Ptr.U8_32"
+  ]),
+  ("verifier_group_09", #[
+    "read_ext_vec_n",
+    "pair_mul"
+  ]),
+  ("verifier_group_10", #[
+    "read_digest_vec_at_n",
+    "read_merkle_cap_vec_n",
+    "read_opt_idx_n",
+    "leaf_hash_at",
+    "fri_fold2",
+    "obs_log_arities",
+    "build_buckets",
+    "rollin",
+    "sample_query_indices",
+    "query_views",
+    "snoc_cap",
+    "two_adic_gen",
+    "pow2",
+    "quotient_eval",
+    "list_length.CommitPhaseMultiStep"
+  ]),
+  ("verifier_group_11", #[
+    "read_u64_vec_vec_n",
+    "read_node_ids_n"
+  ]),
+  ("verifier_group_12", #[
+    "bytes_to_block",
+    "blake3_finish",
+    "blake3_compress_block",
+    "read_sys_circuits_n",
+    "ch_sample8",
+    "ood_loop"
+  ]),
+  ("verifier_group_13", #[
+    "read_vk_cap_n",
+    "read_opt_commit",
+    "prep_count",
+    "heights_max",
+    "verify_one_query",
+    "verify_input_multi",
+    "quotient_degree_of",
+    "claims_acc",
+    "read_claims_n",
+    "list_length.FrontierNode"
+  ]),
+  ("verifier_group_14", #[
+    "compress_ordered",
+    "ood_fold",
+    "list_is_empty.Ptr.U8_32"
+  ]),
+  ("verifier_group_15", #[
+    "select_rows_le",
+    "frontier_level",
+    "accs_onto"
+  ]),
+  ("verifier_group_16", #[
+    "inject_maybe",
+    "rev_onto",
+    "list_lookup.G_2",
+    "list_drop.G_2"
+  ]),
+  ("verifier_group_17", #[
+    "open_2pt_mat",
+    "open_batch_2pt",
+    "open_quotient",
+    "open_prep",
+    "fold_roots",
+    "logup_fingerprint"
+  ]),
+  ("verifier_group_18", #[
+    "list_lookup.U8_8",
+    "list_drop.U8_8"
+  ]),
+  ("verifier_group_19", #[
+    "list_lookup.BatchOpening",
+    "list_length.CommitPhaseProofStep",
+    "list_drop.G"
+  ])
+]
 
 end MultiStark