diff --git a/src/ast/CMakeLists.txt b/src/ast/CMakeLists.txt
index dd1db135c..6a50c3b05 100644
--- a/src/ast/CMakeLists.txt
+++ b/src/ast/CMakeLists.txt
@@ -46,7 +46,6 @@ z3_add_component(ast
     recfun_decl_plugin.cpp
     reg_decl_plugins.cpp
     seq_decl_plugin.cpp
-    seq_derive.cpp
     shared_occs.cpp
     special_relations_decl_plugin.cpp
     static_features.cpp
diff --git a/src/ast/rewriter/CMakeLists.txt b/src/ast/rewriter/CMakeLists.txt
index 9d529f9b5..2cdcba510 100644
--- a/src/ast/rewriter/CMakeLists.txt
+++ b/src/ast/rewriter/CMakeLists.txt
@@ -39,6 +39,7 @@ z3_add_component(rewriter
     rewriter.cpp
     seq_axioms.cpp
     seq_eq_solver.cpp
+    seq_derive.cpp
     seq_rewriter.cpp
     seq_skolem.cpp
     th_rewriter.cpp
diff --git a/src/ast/seq_derive.cpp b/src/ast/rewriter/seq_derive.cpp
similarity index 99%
rename from src/ast/seq_derive.cpp
rename to src/ast/rewriter/seq_derive.cpp
index 96ec04059..a4c598948 100644
--- a/src/ast/seq_derive.cpp
+++ b/src/ast/rewriter/seq_derive.cpp
@@ -21,7 +21,7 @@ Authors:
 
 --*/
 
-#include "ast/seq_derive.h"
+#include "ast/rewriter/seq_derive.h"
 #include "ast/ast_pp.h"
 #include "ast/array_decl_plugin.h"
 #include "ast/rewriter/bool_rewriter.h"
diff --git a/src/ast/seq_derive.h b/src/ast/rewriter/seq_derive.h
similarity index 100%
rename from src/ast/seq_derive.h
rename to src/ast/rewriter/seq_derive.h
diff --git a/src/ast/rewriter/seq_rewriter.cpp b/src/ast/rewriter/seq_rewriter.cpp
index b6e472b1a..212f97a8a 100644
--- a/src/ast/rewriter/seq_rewriter.cpp
+++ b/src/ast/rewriter/seq_rewriter.cpp
@@ -2921,390 +2921,6 @@ expr_ref seq_rewriter::mk_derivative(expr* ele, expr* r) {
     return m_derive(ele, r);
 }
 
-expr_ref seq_rewriter::mk_antimirov_deriv(expr* e, expr* r, expr* path) {
-    // Ensure references are owned
-    expr_ref _e(e, m()), _path(path, m()), _r(r, m());
-    expr_ref result(m_op_cache.find(OP_RE_DERIVATIVE, e, r, path), m());
-    if (!result) {
-        mk_antimirov_deriv_rec(e, r, path, result);
-        m_op_cache.insert(OP_RE_DERIVATIVE, e, r, path, result);
-        STRACE(seq_regex, tout << "D(" << mk_pp(e, m()) << "," << mk_pp(r, m()) << "," << mk_pp(path, m()) << ")" << std::endl;);
-        STRACE(seq_regex, tout << "= " << mk_pp(result, m()) << std::endl;);
-    }
-    return result;
-}
-
-void seq_rewriter::mk_antimirov_deriv_rec(expr* e, expr* r, expr* path, expr_ref& result) {
-    sort* seq_sort = nullptr, * ele_sort = nullptr;
-    expr_ref _r(r, m()), _path(path, m());
-    VERIFY(m_util.is_re(r, seq_sort));
-    VERIFY(m_util.is_seq(seq_sort, ele_sort));
-    SASSERT(ele_sort == e->get_sort());
-    expr* r1 = nullptr, * r2 = nullptr, * c = nullptr;
-    expr_ref c1(m());
-    expr_ref c2(m());
-    auto nothing = [&]() { return expr_ref(re().mk_empty(r->get_sort()), m()); };
-    auto epsilon = [&]() { return expr_ref(re().mk_epsilon(seq_sort), m()); };
-    auto dotstar = [&]() { return expr_ref(re().mk_full_seq(r->get_sort()), m()); };
-    unsigned lo = 0, hi = 0;
-    if (re().is_empty(r) || re().is_epsilon(r))
-        // D(e,[]) = D(e,()) = []
-        result = nothing();
-    else if (re().is_full_seq(r) || re().is_dot_plus(r))
-        // D(e,.*) = D(e,.+) = .*
-        result = dotstar();
-    else if (re().is_full_char(r))
-        // D(e,.) = ()
-        result = epsilon();
-    else if (re().is_to_re(r, r1)) {
-        expr_ref h(m());
-        expr_ref t(m());
-        // here r1 is a sequence
-        if (get_head_tail(r1, h, t)) {
-            if (eq_char(e, h))
-                result = re().mk_to_re(t);
-            else if (neq_char(e, h))
-                result = nothing();
-            else
-                result = re().mk_ite_simplify(m().mk_eq(e, h), re().mk_to_re(t), nothing());
-        }
-        else {
-            // observe that the precondition |r1|>0 is is implied by c1 for use of mk_seq_first
-            {
-                auto is_non_empty = m().mk_not(m().mk_eq(r1, str().mk_empty(seq_sort)));
-                auto eq_first = m().mk_eq(mk_seq_first(r1), e);
-                m_br.mk_and(is_non_empty, eq_first, c1);
-            }
-            m_br.mk_and(path, c1, c2);
-            if (m().is_false(c2))
-                result = nothing();
-            else
-                // observe that the precondition |r1|>0 is implied by c1 for use of mk_seq_rest
-                result = m().mk_ite(c1, re().mk_to_re(mk_seq_rest(r1)), nothing());
-        }
-    }
-    else if (re().is_reverse(r, r2))
-        if (re().is_to_re(r2, r1)) {
-            // here r1 is a sequence
-            // observe that the precondition |r1|>0 of mk_seq_last is implied by c1
-            {
-                auto is_non_empty = m().mk_not(m().mk_eq(r1, str().mk_empty(seq_sort)));
-                auto eq_last = m().mk_eq(mk_seq_last(r1), e);
-                m_br.mk_and(is_non_empty, eq_last, c1);
-            }
-            m_br.mk_and(path, c1, c2);
-            if (m().is_false(c2))
-                result = nothing();
-            else
-                // observe that the precondition |r1|>0 of mk_seq_rest is implied by c1
-                result = re().mk_ite_simplify(c1, re().mk_reverse(re().mk_to_re(mk_seq_butlast(r1))), nothing());
-        }
-        else {
-            result = mk_regex_reverse(r2);
-            if (result.get() == r)
-                //r2 is an uninterpreted regex that is stuck
-                //for example if r = (re.reverse R) where R is a regex variable then
-                //here result.get() == r
-                result = re().mk_derivative(e, result);
-            else
-                result = mk_antimirov_deriv(e, result, path);
-        }
-    else if (re().is_concat(r, r1, r2)) {
-        expr_ref r1nullable(is_nullable(r1), m());
-        c1 = mk_antimirov_deriv_concat(mk_antimirov_deriv(e, r1, path), r2);
-        expr_ref r1nullable_and_path(m());
-        m_br.mk_and(r1nullable, path, r1nullable_and_path);
-        if (m().is_false(r1nullable_and_path))
-            // D(e,r1)r2
-            result = c1;
-        else
-            // D(e,r1)r2|(ite (r1nullable) (D(e,r2)) [])
-            // observe that (mk_ite_simplify(true, D(e,r2), []) = D(e,r2)
-            result = mk_antimirov_deriv_union(c1, re().mk_ite_simplify(r1nullable, mk_antimirov_deriv(e, r2, path), nothing()));
-    }
-    else if (m().is_ite(r, c, r1, r2)) {
-        {
-            auto cp = m().mk_and(c, path);
-            c1 = simplify_path(e, cp);
-        }
-        {
-            auto notc = m().mk_not(c);
-            auto np = m().mk_and(notc, path);
-            c2 = simplify_path(e, np);
-        }
-        if (m().is_false(c1))
-            result = mk_antimirov_deriv(e, r2, c2);
-        else if (m().is_false(c2))
-            result = mk_antimirov_deriv(e, r1, c1);
-        else
-            result = re().mk_ite_simplify(c, mk_antimirov_deriv(e, r1, c1), mk_antimirov_deriv(e, r2, c2));
-    }
-    else if (re().is_range(r, r1, r2)) {
-        expr_ref range(m());
-        expr_ref psi(m().mk_false(), m());
-        if (str().is_unit_string(r1, c1) && str().is_unit_string(r2, c2)) {
-            // SASSERT(u().is_char(c1));
-            // SASSERT(u().is_char(c2));
-            // case: c1 <= e <= c2
-            // deterministic evaluation for range bounds
-            auto a_le = u().mk_le(c1, e);
-            auto b_le = u().mk_le(e, c2);
-            auto rng_cond = m().mk_and(a_le, b_le);
-            range = simplify_path(e, rng_cond);
-            psi = simplify_path(e, m().mk_and(path, range));
-        }
-        else if (!str().is_string(r1) && str().is_unit_string(r2, c2)) {
-            SASSERT(u().is_char(c2));
-            // r1 nonground: |r1|=1 & r1[0] <= e <= c2
-            expr_ref one(m_autil.mk_int(1), m());
-            expr_ref zero(m_autil.mk_int(0), m());
-            expr_ref r1_length_eq_one(m().mk_eq(str().mk_length(r1), one), m());
-            expr_ref r1_0(str().mk_nth_i(r1, zero), m());
-            range = simplify_path(e, m().mk_and(r1_length_eq_one, m().mk_and(u().mk_le(r1_0, e), u().mk_le(e, c2))));
-            psi = simplify_path(e, m().mk_and(path, range));
-        }
-        else if (!str().is_string(r2) && str().is_unit_string(r1, c1)) {
-            SASSERT(u().is_char(c1));
-            // r2 nonground: |r2|=1 & c1 <= e <= r2_0
-            expr_ref one(m_autil.mk_int(1), m());
-            expr_ref zero(m_autil.mk_int(0), m());
-            expr_ref r2_length_eq_one(m().mk_eq(str().mk_length(r2), one), m());
-            expr_ref r2_0(str().mk_nth_i(r2, zero), m());
-            range = simplify_path(e, m().mk_and(r2_length_eq_one, m().mk_and(u().mk_le(c1, e), u().mk_le(e, r2_0))));
-            psi = simplify_path(e, m().mk_and(path, range));
-        }
-        else if (!str().is_string(r1) && !str().is_string(r2)) {
-            // both r1 and r2 nonground: |r1|=1 & |r2|=1 & r1[0] <= e <= r2[0]
-            expr_ref one(m_autil.mk_int(1), m());
-            expr_ref zero(m_autil.mk_int(0), m());
-            expr_ref r1_length_eq_one(m().mk_eq(str().mk_length(r1), one), m());
-            expr_ref r1_0(str().mk_nth_i(r1, zero), m());
-            expr_ref r2_length_eq_one(m().mk_eq(str().mk_length(r2), one), m());
-            expr_ref r2_0(str().mk_nth_i(r2, zero), m());
-            range = simplify_path(e, m().mk_and(r1_length_eq_one, m().mk_and(r2_length_eq_one, m().mk_and(u().mk_le(r1_0, e), u().mk_le(e, r2_0)))));
-            psi = simplify_path(e, m().mk_and(path, range));
-        }
-        if (m().is_false(psi))
-            result = nothing();
-        else
-            result = re().mk_ite_simplify(range, epsilon(), nothing());
-    }
-    else if (re().is_union(r, r1, r2))
-        result = mk_antimirov_deriv_union(mk_antimirov_deriv(e, r1, path), mk_antimirov_deriv(e, r2, path));
-    else if (re().is_intersection(r, r1, r2))
-        result = mk_antimirov_deriv_intersection(e, 
-            mk_antimirov_deriv(e, r1, path),
-            mk_antimirov_deriv(e, r2, path), m().mk_true());
-    else if (re().is_star(r, r1) || re().is_plus(r, r1) || (re().is_loop(r, r1, lo) && 0 <= lo && lo <= 1))
-        result = mk_antimirov_deriv_concat(mk_antimirov_deriv(e, r1, path), re().mk_star(r1));
-    else if (re().is_loop(r, r1, lo))
-        result = mk_antimirov_deriv_concat(mk_antimirov_deriv(e, r1, path), re().mk_loop(r1, lo - 1));
-    else if (re().is_loop(r, r1, lo, hi)) {
-        if ((lo == 0 && hi == 0) || hi < lo)
-            result = nothing();
-        else {
-            expr_ref t(re().mk_loop_proper(r1, (lo == 0 ? 0 : lo - 1), hi - 1), m());
-            result = mk_antimirov_deriv_concat(mk_antimirov_deriv(e, r1, path), t);
-        }
-    }
-    else if (re().is_opt(r, r1))
-        result = mk_antimirov_deriv(e, r1, path);
-    else if (re().is_complement(r, r1))
-        // D(e,~r1) = ~D(e,r1)
-        result = mk_antimirov_deriv_negate(e, mk_antimirov_deriv(e, r1, path));
-    else if (re().is_diff(r, r1, r2))
-        result = mk_antimirov_deriv_intersection(e, 
-            mk_antimirov_deriv(e, r1, path),
-            mk_antimirov_deriv_negate(e, mk_antimirov_deriv(e, r2, path)), m().mk_true());
-    else if (re().is_of_pred(r, r1)) {
-        array_util array(m());
-        expr* args[2] = { r1, e };
-        result = array.mk_select(2, args);
-        // Use mk_der_cond to normalize
-        result = mk_der_cond(result, e, seq_sort);
-    }
-    else
-        // stuck cases
-        result = re().mk_derivative(e, r);
-}
-
-expr_ref seq_rewriter::mk_antimirov_deriv_intersection(expr* e, expr* d1, expr* d2, expr* path) {
-    sort* seq_sort = nullptr, * ele_sort = nullptr;
-    VERIFY(m_util.is_re(d1, seq_sort));
-    VERIFY(m_util.is_seq(seq_sort, ele_sort));
-    expr_ref result(m());
-    expr* c, * a, * b;
-    if (m_re_deriv_depth >= m_max_re_deriv_depth) {
-        // Depth limit reached: construct intersection without further decomposition
-        result = mk_regex_inter_normalize(d1, d2);
-    }
-    else if (re().is_empty(d1))
-        result = d1;
-    else if (re().is_empty(d2))
-        result = d2;
-    else if (m().is_ite(d1, c, a, b)) {
-        expr_ref path_and_c(simplify_path(e, m().mk_and(path, c)), m());
-        expr_ref path_and_notc(simplify_path(e, m().mk_and(path, m().mk_not(c))), m());
-        ++m_re_deriv_depth;
-        if (m().is_false(path_and_c))
-            result = mk_antimirov_deriv_intersection(e, b, d2, path);
-        else if (m().is_false(path_and_notc))
-            result = mk_antimirov_deriv_intersection(e, a, d2, path);
-        else
-            result = m().mk_ite(c, mk_antimirov_deriv_intersection(e, a, d2, path_and_c),
-                mk_antimirov_deriv_intersection(e, b, d2, path_and_notc));
-        --m_re_deriv_depth;
-    }
-    else if (m().is_ite(d2)) {
-        // swap d1 and d2
-        ++m_re_deriv_depth;
-        result = mk_antimirov_deriv_intersection(e, d2, d1, path);
-        --m_re_deriv_depth;
-    }
-    else if (d1 == d2 || re().is_full_seq(d2))
-        result = mk_antimirov_deriv_restrict(e, d1, path);
-    else if (re().is_full_seq(d1))
-        result = mk_antimirov_deriv_restrict(e, d2, path);
-    else if (re().is_union(d1, a, b)) {
-        // distribute intersection over the union in d1
-        ++m_re_deriv_depth;
-        result = mk_antimirov_deriv_union(mk_antimirov_deriv_intersection(e, a, d2, path),
-            mk_antimirov_deriv_intersection(e, b, d2, path));
-        --m_re_deriv_depth;
-    }
-    else if (re().is_union(d2, a, b)) {
-        // distribute intersection over the union in d2
-        ++m_re_deriv_depth;
-        result = mk_antimirov_deriv_union(mk_antimirov_deriv_intersection(e, d1, a, path),
-            mk_antimirov_deriv_intersection(e, d1, b, path));
-        --m_re_deriv_depth;
-    }
-    else
-        result = mk_regex_inter_normalize(d1, d2);
-    return result;
-}
-
-expr_ref seq_rewriter::mk_antimirov_deriv_concat(expr* d, expr* r) {
-    expr_ref result(m());
-    expr_ref _r(r, m()), _d(d, m());
-    expr* c, * t, * e;
-    if (m_re_deriv_depth >= m_max_re_deriv_depth) {
-        // Depth limit reached: construct concat without further decomposition
-        result = mk_re_append(d, r);
-    }
-    else if (m().is_ite(d, c, t, e)) {
-        ++m_re_deriv_depth;
-        auto r2 = mk_antimirov_deriv_concat(e, r);
-        auto r1 = mk_antimirov_deriv_concat(t, r);
-        --m_re_deriv_depth;
-        result = m().mk_ite(c, r1, r2);
-    }
-    else if (re().is_union(d, t, e)) {
-        ++m_re_deriv_depth;
-        result = mk_antimirov_deriv_union(mk_antimirov_deriv_concat(t, r), mk_antimirov_deriv_concat(e, r));
-        --m_re_deriv_depth;
-    }
-    else
-        result = mk_re_append(d, r);
-    SASSERT(result.get());
-    return result;
-}
-
-expr_ref seq_rewriter::mk_antimirov_deriv_negate(expr* elem, expr* d) {
-    sort* seq_sort = nullptr;
-    VERIFY(m_util.is_re(d, seq_sort));
-    auto nothing = [&]() { return expr_ref(re().mk_empty(d->get_sort()), m()); };
-    auto epsilon = [&]() { return expr_ref(re().mk_epsilon(seq_sort), m()); };
-    auto dotstar = [&]() { return expr_ref(re().mk_full_seq(d->get_sort()), m()); };
-    auto dotplus = [&]() { return expr_ref(re().mk_plus(re().mk_full_char(d->get_sort())), m()); };
-    expr_ref result(m());
-    expr* c, * t, * e;
-    if (m_re_deriv_depth >= m_max_re_deriv_depth) {
-        // Depth limit reached: construct complement without further decomposition
-        result = re().mk_complement(d);
-    }
-    else if (re().is_empty(d))
-        result = dotstar();
-    else if (re().is_epsilon(d))
-        result = dotplus();
-    else if (re().is_full_seq(d))
-        result = nothing();
-    else if (re().is_dot_plus(d))
-        result = epsilon();
-    else if (m().is_ite(d, c, t, e)) {
-        ++m_re_deriv_depth;
-        result = m().mk_ite(c, mk_antimirov_deriv_negate(elem, t), mk_antimirov_deriv_negate(elem, e));
-        --m_re_deriv_depth;
-    }
-    else if (re().is_union(d, t, e)) {
-        ++m_re_deriv_depth;
-        result = mk_antimirov_deriv_intersection(elem, mk_antimirov_deriv_negate(elem, t), mk_antimirov_deriv_negate(elem, e), m().mk_true());
-        --m_re_deriv_depth;
-    }
-    else if (re().is_intersection(d, t, e)) {
-        ++m_re_deriv_depth;
-        result = mk_antimirov_deriv_union(mk_antimirov_deriv_negate(elem, t), mk_antimirov_deriv_negate(elem, e));
-        --m_re_deriv_depth;
-    }
-    else if (re().is_complement(d, t))
-        result = t;
-    else
-        result = re().mk_complement(d);
-    return result;
-}
-
-expr_ref seq_rewriter::mk_antimirov_deriv_union(expr* d1, expr* d2) {
-    sort* seq_sort = nullptr, * ele_sort = nullptr;
-    VERIFY(m_util.is_re(d1, seq_sort));
-    VERIFY(m_util.is_seq(seq_sort, ele_sort));
-    expr_ref result(m());
-    expr* c1, * t1, * e1, * c2, * t2, * e2;
-    if (m().is_ite(d1, c1, t1, e1) && m().is_ite(d2, c2, t2, e2)  && c1 == c2)
-        // eliminate duplicate branching on exactly the same condition
-        result = m().mk_ite(c1, mk_antimirov_deriv_union(t1, t2), mk_antimirov_deriv_union(e1, e2));
-    else
-        result = mk_regex_union_normalize(d1, d2);
-    return result;
-}
-
-// restrict the guards of all conditionals id d and simplify the resulting derivative
-// restrict(if(c, a, b), cond) = if(c, restrict(a, cond & c), restrict(b, cond & ~c))
-// restrict(a U b, cond) = restrict(a, cond) U restrict(b, cond)
-//     where {} U X = X, X U X = X
-// restrict(R, cond) = R 
-// 
-// restrict(d, false) = []
-// 
-// it is already assumed that the restriction takes place within a branch
-// so the condition is not added explicitly but propagated down in order to eliminate 
-// infeasible cases
-expr_ref seq_rewriter::mk_antimirov_deriv_restrict(expr* e, expr* d, expr* cond) {
-    expr_ref result(d, m());
-    expr_ref _cond(cond, m());
-    expr* c, * a, * b;
-    if (m().is_false(cond))
-        result = re().mk_empty(d->get_sort());
-    else if (re().is_empty(d) || m().is_true(cond))
-        result = d;
-    else if (m_re_deriv_depth >= m_max_re_deriv_depth)
-        result = d;
-    else if (m().is_ite(d, c, a, b)) {
-        expr_ref path_and_c(simplify_path(e, m().mk_and(cond, c)), m());
-        expr_ref path_and_notc(simplify_path(e, m().mk_and(cond, m().mk_not(c))), m());
-        ++m_re_deriv_depth;
-        result = re().mk_ite_simplify(c, mk_antimirov_deriv_restrict(e, a, path_and_c),
-            mk_antimirov_deriv_restrict(e, b, path_and_notc));
-        --m_re_deriv_depth;
-    }
-    else if (re().is_union(d, a, b)) {
-        ++m_re_deriv_depth;
-        expr_ref a1(mk_antimirov_deriv_restrict(e, a, cond), m());
-        expr_ref b1(mk_antimirov_deriv_restrict(e, b, cond), m());
-        --m_re_deriv_depth;
-        result = mk_antimirov_deriv_union(a1, b1);
-    }
-    return result;
-}
 
 expr_ref seq_rewriter::mk_regex_union_normalize(expr* r1, expr* r2) {
     expr_ref _r1(r1, m()), _r2(r2, m());
@@ -3551,29 +3167,6 @@ expr_ref seq_rewriter::mk_regex_concat(expr* r, expr* s) {
     return result;
 }
 
-expr_ref seq_rewriter::mk_in_antimirov(expr* s, expr* d){
-    expr_ref result(mk_in_antimirov_rec(s, d), m());
-    return result;
-}
-
-expr_ref seq_rewriter::mk_in_antimirov_rec(expr* s, expr* d) {
-    expr* c, * d1, * d2;
-    expr_ref result(m());
-    if (re().is_full_seq(d) || (str().min_length(s) > 0 && re().is_dot_plus(d)))
-        // s in .* <==> true, also: s in .+ <==> true when |s|>0
-        result = m().mk_true();
-    else if (re().is_empty(d) || (str().min_length(s) > 0 && re().is_epsilon(d)))
-        // s in [] <==> false, also: s in () <==> false when |s|>0
-        result = m().mk_false();
-    else if (m().is_ite(d, c, d1, d2))
-        result = re().mk_ite_simplify(c, mk_in_antimirov_rec(s, d1), mk_in_antimirov_rec(s, d2));
-    else if (re().is_union(d, d1, d2))
-        m_br.mk_or(mk_in_antimirov_rec(s, d1), mk_in_antimirov_rec(s, d2), result);
-    else
-        result = re().mk_in_re(s, d);
-    return result;
-}
-
 /*
 * calls elim_condition
 */
diff --git a/src/ast/rewriter/seq_rewriter.h b/src/ast/rewriter/seq_rewriter.h
index 9668c299c..70b382457 100644
--- a/src/ast/rewriter/seq_rewriter.h
+++ b/src/ast/rewriter/seq_rewriter.h
@@ -19,7 +19,7 @@ Notes:
 #pragma once
 
 #include "ast/seq_decl_plugin.h"
-#include "ast/seq_derive.h"
+#include "ast/rewriter/seq_derive.h"
 #include "ast/ast_pp.h"
 #include "ast/arith_decl_plugin.h"
 #include "ast/rewriter/rewriter_types.h"
@@ -191,17 +191,6 @@ class seq_rewriter {
     bool check_deriv_normal_form(expr* r, int level = 3);
     #endif
 
-    void mk_antimirov_deriv_rec(expr* e, expr* r, expr* path, expr_ref& result);
-
-    expr_ref mk_antimirov_deriv(expr* e, expr* r, expr* path);
-    expr_ref mk_in_antimirov_rec(expr* s, expr* d);
-    expr_ref mk_in_antimirov(expr* s, expr* d);
-
-    expr_ref mk_antimirov_deriv_intersection(expr* elem, expr* d1, expr* d2, expr* path);
-    expr_ref mk_antimirov_deriv_concat(expr* d, expr* r);
-    expr_ref mk_antimirov_deriv_negate(expr* elem, expr* d);
-    expr_ref mk_antimirov_deriv_union(expr* d1, expr* d2);
-    expr_ref mk_antimirov_deriv_restrict(expr* elem, expr* d1, expr* cond);
     expr_ref mk_regex_reverse(expr* r);
     expr_ref mk_regex_concat(expr* r1, expr* r2);