diff --git a/compiler/can/src/builtins.rs b/compiler/can/src/builtins.rs
index b6d13be1da..4183f7cb99 100644
--- a/compiler/can/src/builtins.rs
+++ b/compiler/can/src/builtins.rs
@@ -455,8 +455,7 @@ fn num_add_wrap(symbol: Symbol, var_store: &mut VarStore) -> Def {
     num_binop(symbol, var_store, LowLevel::NumAddWrap)
 }
 
-/// Num.addChecked : Num a, Num a -> Result (Num a) [ Overflow ]*
-fn num_add_checked(symbol: Symbol, var_store: &mut VarStore) -> Def {
+fn num_overflow_checked(symbol: Symbol, var_store: &mut VarStore, lowlevel: LowLevel) -> Def {
     let bool_var = var_store.fresh();
     let num_var_1 = var_store.fresh();
     let num_var_2 = var_store.fresh();
@@ -464,7 +463,7 @@ fn num_add_checked(symbol: Symbol, var_store: &mut VarStore) -> Def {
     let ret_var = var_store.fresh();
     let record_var = var_store.fresh();
 
-    // let arg_3 = RunLowLevel NumAddChecked arg_1 arg_2
+    // let arg_3 = RunLowLevel NumXXXChecked arg_1 arg_2
     //
     // if arg_3.b then
     //  # overflow
@@ -517,11 +516,11 @@ fn num_add_checked(symbol: Symbol, var_store: &mut VarStore) -> Def {
         ),
     };
 
-    // arg_3 = RunLowLevel NumAddChecked arg_1 arg_2
+    // arg_3 = RunLowLevel NumXXXChecked arg_1 arg_2
     let def = crate::def::Def {
         loc_pattern: no_region(Pattern::Identifier(Symbol::ARG_3)),
         loc_expr: no_region(RunLowLevel {
-            op: LowLevel::NumAddChecked,
+            op: lowlevel,
             args: vec![
                 (num_var_1, Var(Symbol::ARG_1)),
                 (num_var_2, Var(Symbol::ARG_2)),
@@ -544,6 +543,11 @@ fn num_add_checked(symbol: Symbol, var_store: &mut VarStore) -> Def {
     )
 }
 
+/// Num.addChecked : Num a, Num a -> Result (Num a) [ Overflow ]*
+fn num_add_checked(symbol: Symbol, var_store: &mut VarStore) -> Def {
+    num_overflow_checked(symbol, var_store, LowLevel::NumAddChecked)
+}
+
 /// Num.sub : Num a, Num a -> Num a
 fn num_sub(symbol: Symbol, var_store: &mut VarStore) -> Def {
     num_binop(symbol, var_store, LowLevel::NumSub)
@@ -556,91 +560,7 @@ fn num_sub_wrap(symbol: Symbol, var_store: &mut VarStore) -> Def {
 
 /// Num.subChecked : Num a, Num a -> Result (Num a) [ Overflow ]*
 fn num_sub_checked(symbol: Symbol, var_store: &mut VarStore) -> Def {
-    let bool_var = var_store.fresh();
-    let num_var_1 = var_store.fresh();
-    let num_var_2 = var_store.fresh();
-    let num_var_3 = var_store.fresh();
-    let ret_var = var_store.fresh();
-    let record_var = var_store.fresh();
-
-    // let arg_3 = RunLowLevel NumSubChecked arg_1 arg_2
-    //
-    // if arg_3.b then
-    //  # overflow
-    //  Err Overflow
-    // else
-    //  # all is well
-    //  Ok arg_3.a
-
-    let cont = If {
-        branch_var: ret_var,
-        cond_var: bool_var,
-        branches: vec![(
-            // if-condition
-            no_region(
-                // arg_3.b
-                Access {
-                    record_var,
-                    ext_var: var_store.fresh(),
-                    field: "b".into(),
-                    field_var: var_store.fresh(),
-                    loc_expr: Box::new(no_region(Var(Symbol::ARG_3))),
-                },
-            ),
-            // overflow!
-            no_region(tag(
-                "Err",
-                vec![tag("Overflow", Vec::new(), var_store)],
-                var_store,
-            )),
-        )],
-        final_else: Box::new(
-            // all is well
-            no_region(
-                // Ok arg_3.a
-                tag(
-                    "Ok",
-                    vec![
-                        // arg_3.a
-                        Access {
-                            record_var,
-                            ext_var: var_store.fresh(),
-                            field: "a".into(),
-                            field_var: num_var_3,
-                            loc_expr: Box::new(no_region(Var(Symbol::ARG_3))),
-                        },
-                    ],
-                    var_store,
-                ),
-            ),
-        ),
-    };
-
-    // arg_3 = RunLowLevel NumSubChecked arg_1 arg_2
-    let def = crate::def::Def {
-        loc_pattern: no_region(Pattern::Identifier(Symbol::ARG_3)),
-        loc_expr: no_region(RunLowLevel {
-            op: LowLevel::NumSubChecked,
-            args: vec![
-                (num_var_1, Var(Symbol::ARG_1)),
-                (num_var_2, Var(Symbol::ARG_2)),
-            ],
-            ret_var: record_var,
-        }),
-        expr_var: record_var,
-        pattern_vars: SendMap::default(),
-        annotation: None,
-    };
-
-    let body = LetNonRec(Box::new(def), Box::new(no_region(cont)), ret_var);
-
-    defn(
-        symbol,
-        vec![(num_var_1, Symbol::ARG_1), (num_var_2, Symbol::ARG_2)],
-        var_store,
-        body,
-        ret_var,
-    )
+    num_overflow_checked(symbol, var_store, LowLevel::NumSubChecked)
 }
 
 /// Num.mul : Num a, Num a -> Num a
@@ -655,91 +575,7 @@ fn num_mul_wrap(symbol: Symbol, var_store: &mut VarStore) -> Def {
 
 /// Num.mulChecked : Num a, Num a -> Result (Num a) [ Overflow ]*
 fn num_mul_checked(symbol: Symbol, var_store: &mut VarStore) -> Def {
-    let bool_var = var_store.fresh();
-    let num_var_1 = var_store.fresh();
-    let num_var_2 = var_store.fresh();
-    let num_var_3 = var_store.fresh();
-    let ret_var = var_store.fresh();
-    let record_var = var_store.fresh();
-
-    // let arg_3 = RunLowLevel NumMulChecked arg_1 arg_2
-    //
-    // if arg_3.b then
-    //  # overflow
-    //  Err Overflow
-    // else
-    //  # all is well
-    //  Ok arg_3.a
-
-    let cont = If {
-        branch_var: ret_var,
-        cond_var: bool_var,
-        branches: vec![(
-            // if-condition
-            no_region(
-                // arg_3.b
-                Access {
-                    record_var,
-                    ext_var: var_store.fresh(),
-                    field: "b".into(),
-                    field_var: var_store.fresh(),
-                    loc_expr: Box::new(no_region(Var(Symbol::ARG_3))),
-                },
-            ),
-            // overflow!
-            no_region(tag(
-                "Err",
-                vec![tag("Overflow", Vec::new(), var_store)],
-                var_store,
-            )),
-        )],
-        final_else: Box::new(
-            // all is well
-            no_region(
-                // Ok arg_3.a
-                tag(
-                    "Ok",
-                    vec![
-                        // arg_3.a
-                        Access {
-                            record_var,
-                            ext_var: var_store.fresh(),
-                            field: "a".into(),
-                            field_var: num_var_3,
-                            loc_expr: Box::new(no_region(Var(Symbol::ARG_3))),
-                        },
-                    ],
-                    var_store,
-                ),
-            ),
-        ),
-    };
-
-    // arg_3 = RunLowLevel NumMulChecked arg_1 arg_2
-    let def = crate::def::Def {
-        loc_pattern: no_region(Pattern::Identifier(Symbol::ARG_3)),
-        loc_expr: no_region(RunLowLevel {
-            op: LowLevel::NumMulChecked,
-            args: vec![
-                (num_var_1, Var(Symbol::ARG_1)),
-                (num_var_2, Var(Symbol::ARG_2)),
-            ],
-            ret_var: record_var,
-        }),
-        expr_var: record_var,
-        pattern_vars: SendMap::default(),
-        annotation: None,
-    };
-
-    let body = LetNonRec(Box::new(def), Box::new(no_region(cont)), ret_var);
-
-    defn(
-        symbol,
-        vec![(num_var_1, Symbol::ARG_1), (num_var_2, Symbol::ARG_2)],
-        var_store,
-        body,
-        ret_var,
-    )
+    num_overflow_checked(symbol, var_store, LowLevel::NumMulChecked)
 }
 
 /// Num.isGt : Num a, Num a -> Bool