diff --git a/src/cc/Sidekick_cc.ml b/src/cc/Sidekick_cc.ml
index 949e1230..ce6275fa 100644
--- a/src/cc/Sidekick_cc.ml
+++ b/src/cc/Sidekick_cc.ml
@@ -146,8 +146,6 @@ module Make (A: CC_ARG)
     let[@inline] set_field f b t = t.n_bits <- Bits.set f b t.n_bits
   end
 
-  module N_tbl = CCHashtbl.Make(N)
-
   (* non-recursive, inlinable function for [find] *)
   let[@inline] find_ (n:node) : repr =
     let n2 = n.n_root in
diff --git a/src/drup/sidekick_drup.ml b/src/drup/sidekick_drup.ml
index cbe0d992..70e47de8 100644
--- a/src/drup/sidekick_drup.ml
+++ b/src/drup/sidekick_drup.ml
@@ -128,7 +128,6 @@ module Make() : S = struct
     val pp : t Fmt.printer
     val of_list : store -> atom list -> t
     val of_iter : store -> atom Iter.t -> t
-    module Set : CCSet.S with type elt = t
     module Tbl : CCHashtbl.S with type key = t
   end = struct
     type t = {
@@ -171,7 +170,6 @@ module Make() : S = struct
       let[@inline] equal a b = a.id = b.id
       let[@inline] compare a b = compare a.id b.id
     end
-    module Set = CCSet.Make(As_key)
     module Tbl = CCHashtbl.Make(As_key)
   end
   type clause = Clause.t
diff --git a/src/sat/Solver.ml b/src/sat/Solver.ml
index c8c0cf04..e7537f05 100644
--- a/src/sat/Solver.ml
+++ b/src/sat/Solver.ml
@@ -28,10 +28,8 @@ module Make(Plugin : PLUGIN)
   (* a boolean variable (positive int) *)
   module Var0 : sig
     include Int_id.S
-    module Set : Set.S with type elt = t
   end = struct
     include Int_id.Make()
-    module Set = Util.Int_set
   end
   type var = Var0.t
 
@@ -46,7 +44,6 @@ module Make(Plugin : PLUGIN)
     val abs : t -> t
     val pa : var -> t
     val na : var -> t
-    module Set : CCSet.S with type elt = t
   end = struct
     include Int_id.Make()
     let[@inline] neg i = (i lxor 1)
@@ -57,7 +54,6 @@ module Make(Plugin : PLUGIN)
     let[@inline] abs a = a land (lnot 1)
     let[@inline] var a = Var0.of_int_unsafe (a lsr 1)
     let[@inline] na v = (((v:var:>int) lsl 1) lor 1)
-    module Set = Util.Int_set
   end
   type atom = Atom0.t
 
@@ -213,7 +209,7 @@ module Make(Plugin : PLUGIN)
       let[@inline] pp_sign a = if sign a then "+" else "-"
 
       (* print level+reason of assignment *)
-      let debug_reason self out = function
+      let debug_reason _self out = function
         | n, _ when n < 0 -> Format.fprintf out "%%"
         | n, None -> Format.fprintf out "%d" n
         | n, Some Decision -> Format.fprintf out "@@%d" n
@@ -1890,7 +1886,6 @@ module Make(Plugin : PLUGIN)
     let module M = struct
       type nonrec lit = lit
       type clause = Clause.t
-      type proof = Proof.t
       let unsat_conflict = unsat_conflict
       let unsat_assumptions = unsat_assumptions
     end in
diff --git a/src/th-data/Sidekick_th_data.ml b/src/th-data/Sidekick_th_data.ml
index 51a3b42d..26392232 100644
--- a/src/th-data/Sidekick_th_data.ml
+++ b/src/th-data/Sidekick_th_data.ml
@@ -34,9 +34,6 @@ module type DATA_TY = sig
   val view : t -> (cstor, t) data_ty_view
 
   val cstor_args : cstor -> t Iter.t
-
-  (** A table indexed by types. *)
-  module Tbl : Hashtbl.S with type key = t
 end
 
 (** {2 Cardinality of types} *)
@@ -200,7 +197,6 @@ module Make(A : ARG) : S with module A = A = struct
   module T = A.S.T.Term
   module N = SI.CC.N
   module Ty = A.S.T.Ty
-  module Fun = A.S.T.Fun
   module Expl = SI.CC.Expl
 
   module Card = Compute_card(A)