diff --git a/.github/workflows/run_sanitizers_leak.suppressions b/.github/workflows/run_sanitizers_leak.suppressions
new file mode 100644
index 00000000000000..49ef9963d5dfbb
--- /dev/null
+++ b/.github/workflows/run_sanitizers_leak.suppressions
@@ -0,0 +1,13 @@
+# websocket tests
+leak:mbedtls_ssl_setup
+
+# sqlite tests
+leak:*sqlite*
+
+# v
+leak:v__*
+leak:os__*
+leak:string__plus
+leak:malloc_uncollectable
+leak:new_array_from_c_array
+leak:_vinit
diff --git a/.github/workflows/sanitized_ci.yml b/.github/workflows/sanitized_ci.yml
index 19b416901b08cd..a69e6490b755a2 100644
--- a/.github/workflows/sanitized_ci.yml
+++ b/.github/workflows/sanitized_ci.yml
@@ -75,7 +75,7 @@ concurrency:
 jobs:
   tests-sanitize-undefined-clang:
     runs-on: ubuntu-20.04
-    timeout-minutes: 240
+    timeout-minutes: 120
     env:
       VFLAGS: -cc clang
       VJOBS: 1
@@ -101,7 +101,7 @@ jobs:
 
   tests-sanitize-undefined-gcc:
     runs-on: ubuntu-20.04
-    timeout-minutes: 240
+    timeout-minutes: 120
     env:
       VFLAGS: -cc gcc
       VJOBS: 1
@@ -126,7 +126,7 @@ jobs:
 
   tests-sanitize-address-clang:
     runs-on: ubuntu-20.04
-    timeout-minutes: 240
+    timeout-minutes: 300
     env:
       VFLAGS: -cc clang
       VJOBS: 1
@@ -146,16 +146,16 @@ jobs:
       - name: Recompile V with -cstrict
         run: ./v -cg -cstrict -o v cmd/v
       - name: Self tests (-fsanitize=address)
-        run: ASAN_OPTIONS=detect_leaks=0 ./v -cflags "-fsanitize=address,pointer-compare,pointer-subtract" test-self vlib
+        run: ASAN_OPTIONS=detect_leaks=1:fast_unwind_on_malloc=0 LSAN_OPTIONS=max_leaks=1:print_suppressions=0:suppressions=.github/workflows/run_sanitizers_leak.suppressions ./v -cflags "-fsanitize=address,pointer-compare,pointer-subtract" test-self vlib
       - name: Self tests (V compiled with -fsanitize=address)
         run: ./v -cflags -fsanitize=address -o v cmd/v &&
-          ASAN_OPTIONS=detect_leaks=0 ./v -cc tcc test-self -asan-compiler vlib
+          ASAN_OPTIONS=detect_leaks=1:fast_unwind_on_malloc=0 LSAN_OPTIONS=max_leaks=1:print_suppressions=0:suppressions=.github/workflows/run_sanitizers_leak.suppressions ./v -cc tcc test-self -asan-compiler vlib
       - name: Build examples (V compiled with -fsanitize=address)
-        run: ASAN_OPTIONS=detect_leaks=0 ./v build-examples
+        run: ASAN_OPTIONS=detect_leaks=1:fast_unwind_on_malloc=0 LSAN_OPTIONS=max_leaks=1:print_suppressions=0:suppressions=.github/workflows/run_sanitizers_leak.suppressions ./v build-examples
 
   tests-sanitize-address-msvc:
     runs-on: windows-2019
-    timeout-minutes: 240
+    timeout-minutes: 30
     env:
       VFLAGS: -cc msvc
       VJOBS: 1
@@ -179,7 +179,7 @@ jobs:
 
   tests-sanitize-address-gcc:
     runs-on: ubuntu-20.04
-    timeout-minutes: 240
+    timeout-minutes: 300
     env:
       VFLAGS: -cc gcc
       VJOBS: 1
@@ -199,13 +199,13 @@ jobs:
       - name: Recompile V with -cstrict
         run: ./v -cg -cstrict -o v cmd/v
       - name: Self tests (-fsanitize=address)
-        run: ASAN_OPTIONS=detect_leaks=0 ./v -cflags -fsanitize=address test-self vlib
+        run: ASAN_OPTIONS=detect_leaks=1:fast_unwind_on_malloc=0 LSAN_OPTIONS=max_leaks=1:print_suppressions=0:suppressions=.github/workflows/run_sanitizers_leak.suppressions ./v -cflags -fsanitize=address test-self vlib
       - name: Self tests (V compiled with -fsanitize=address)
         run:
           ./v -cflags -fsanitize=address,pointer-compare,pointer-subtract -o v cmd/v &&
-          ASAN_OPTIONS=detect_leaks=0 ./v -cc tcc test-self -asan-compiler vlib
+          ASAN_OPTIONS=detect_leaks=1:fast_unwind_on_malloc=0 LSAN_OPTIONS=max_leaks=1:print_suppressions=0:suppressions=.github/workflows/run_sanitizers_leak.suppressions ./v -cc tcc test-self -asan-compiler vlib
       - name: Build examples (V compiled with -fsanitize=address)
-        run: ASAN_OPTIONS=detect_leaks=0 ./v build-examples
+        run: ASAN_OPTIONS=detect_leaks=1:fast_unwind_on_malloc=0 LSAN_OPTIONS=max_leaks=1:print_suppressions=0:suppressions=.github/workflows/run_sanitizers_leak.suppressions ./v build-examples
 
   tests-sanitize-memory-clang:
     runs-on: ubuntu-20.04
diff --git a/vlib/builtin/backtraces_nix.c.v b/vlib/builtin/backtraces_nix.c.v
index 04ceb64c86348d..b3b2355cf731c2 100644
--- a/vlib/builtin/backtraces_nix.c.v
+++ b/vlib/builtin/backtraces_nix.c.v
@@ -106,6 +106,9 @@ fn print_backtrace_skipping_top_frames_linux(skipframes int) bool {
 					output = output.replace(' (discriminator', ': (d.')
 					eprintln('${output:-55s} | ${addr:14s} | ${beforeaddr}')
 				}
+				if sframes.len > 0 {
+					unsafe { C.free(csymbols) }
+				}
 			}
 		}
 	}
diff --git a/vlib/compress/compress.c.v b/vlib/compress/compress.c.v
index 8206874beb0fb3..a5f0ffe6ffe05e 100644
--- a/vlib/compress/compress.c.v
+++ b/vlib/compress/compress.c.v
@@ -24,7 +24,11 @@ pub fn compress(data []u8, flags int) ![]u8 {
 	if u64(out_len) > max_size {
 		return error('compressed data is too large (${out_len} > ${max_size})')
 	}
-	return unsafe { address.vbytes(int(out_len)) }
+	unsafe {
+		ret := address.vbytes(int(out_len)).clone()
+		C.free(address)
+		return ret
+	}
 }
 
 // decompresses an array of bytes based on providing flags and returns the decompressed bytes in a new array
@@ -40,5 +44,10 @@ pub fn decompress(data []u8, flags int) ![]u8 {
 	if u64(out_len) > max_size {
 		return error('decompressed data is too large (${out_len} > ${max_size})')
 	}
-	return unsafe { address.vbytes(int(out_len)) }
+
+	unsafe {
+		ret := address.vbytes(int(out_len)).clone()
+		C.free(address)
+		return ret
+	}
 }
diff --git a/vlib/crypto/ecdsa/ecdsa.v b/vlib/crypto/ecdsa/ecdsa.v
index 424fad19fbb6ea..ae90980c090c8b 100644
--- a/vlib/crypto/ecdsa/ecdsa.v
+++ b/vlib/crypto/ecdsa/ecdsa.v
@@ -227,3 +227,8 @@ pub fn (pub_key PublicKey) equal(other PublicKey) bool {
 	res := C.EC_POINT_cmp(group, point1, point2, ctx)
 	return res == 0
 }
+
+// Clear allocated memory for key
+pub fn key_free(ec_key &C.EC_KEY) {
+	C.EC_KEY_free(ec_key)
+}
diff --git a/vlib/crypto/ecdsa/ecdsa_test.v b/vlib/crypto/ecdsa/ecdsa_test.v
index 94fb996c89dd20..18e3d7ab3cf214 100644
--- a/vlib/crypto/ecdsa/ecdsa_test.v
+++ b/vlib/crypto/ecdsa/ecdsa_test.v
@@ -12,6 +12,7 @@ fn test_ecdsa() {
 	is_valid := pub_key.verify(message, signature) or { panic(err) }
 	println('Signature valid: ${is_valid}')
 	assert is_valid
+	key_free(priv_key.key)
 }
 
 fn test_generate_key() ! {
@@ -19,6 +20,7 @@ fn test_generate_key() ! {
 	pub_key, priv_key := generate_key() or { panic(err) }
 	assert pub_key.key != unsafe { nil }
 	assert priv_key.key != unsafe { nil }
+	key_free(priv_key.key)
 }
 
 fn test_new_key_from_seed() ! {
@@ -27,6 +29,7 @@ fn test_new_key_from_seed() ! {
 	priv_key := new_key_from_seed(seed) or { panic(err) }
 	retrieved_seed := priv_key.seed() or { panic(err) }
 	assert seed == retrieved_seed
+	key_free(priv_key.key)
 }
 
 fn test_sign_and_verify() ! {
@@ -36,6 +39,7 @@ fn test_sign_and_verify() ! {
 	signature := priv_key.sign(message) or { panic(err) }
 	is_valid := pub_key.verify(message, signature) or { panic(err) }
 	assert is_valid
+	key_free(priv_key.key)
 }
 
 fn test_seed() ! {
@@ -43,6 +47,7 @@ fn test_seed() ! {
 	_, priv_key := generate_key() or { panic(err) }
 	seed := priv_key.seed() or { panic(err) }
 	assert seed.len > 0
+	key_free(priv_key.key)
 }
 
 fn test_public_key() ! {
@@ -51,6 +56,9 @@ fn test_public_key() ! {
 	pub_key1 := priv_key.public_key() or { panic(err) }
 	pub_key2, _ := generate_key() or { panic(err) }
 	assert !pub_key1.equal(pub_key2)
+	key_free(priv_key.key)
+	key_free(pub_key1.key)
+	key_free(pub_key2.key)
 }
 
 fn test_private_key_equal() ! {
@@ -59,6 +67,8 @@ fn test_private_key_equal() ! {
 	seed := priv_key1.seed() or { panic(err) }
 	priv_key2 := new_key_from_seed(seed) or { panic(err) }
 	assert priv_key1.equal(priv_key2)
+	key_free(priv_key1.key)
+	key_free(priv_key2.key)
 }
 
 fn test_public_key_equal() ! {
@@ -67,6 +77,9 @@ fn test_public_key_equal() ! {
 	pub_key1 := priv_key.public_key() or { panic(err) }
 	pub_key2 := priv_key.public_key() or { panic(err) }
 	assert pub_key1.equal(pub_key2)
+	key_free(priv_key.key)
+	key_free(pub_key1.key)
+	key_free(pub_key2.key)
 }
 
 fn test_sign_with_new_key_from_seed() ! {
@@ -78,6 +91,8 @@ fn test_sign_with_new_key_from_seed() ! {
 	pub_key := priv_key.public_key() or { panic(err) }
 	is_valid := pub_key.verify(message, signature) or { panic(err) }
 	assert is_valid
+	key_free(priv_key.key)
+	key_free(pub_key.key)
 }
 
 fn test_invalid_signature() ! {
@@ -88,9 +103,11 @@ fn test_invalid_signature() ! {
 	result := pub_key.verify(message, invalid_signature) or {
 		// Expecting verification to fail
 		assert err.msg() == 'Failed to verify signature'
+		key_free(pub_key.key)
 		return
 	}
 	assert !result
+	key_free(pub_key.key)
 }
 
 fn test_different_keys_not_equal() ! {
@@ -98,4 +115,6 @@ fn test_different_keys_not_equal() ! {
 	_, priv_key1 := generate_key() or { panic(err) }
 	_, priv_key2 := generate_key() or { panic(err) }
 	assert !priv_key1.equal(priv_key2)
+	key_free(priv_key1.key)
+	key_free(priv_key2.key)
 }
diff --git a/vlib/db/sqlite/parent_child_test.v b/vlib/db/sqlite/parent_child_test.v
index 684808a5789d61..d164674704f6a2 100644
--- a/vlib/db/sqlite/parent_child_test.v
+++ b/vlib/db/sqlite/parent_child_test.v
@@ -20,7 +20,7 @@ struct Baby {
 }
 
 fn test_main() {
-	db := sqlite.connect(':memory:')!
+	mut db := sqlite.connect(':memory:')!
 
 	sql db {
 		create table Parent
@@ -80,4 +80,6 @@ fn test_main() {
 	assert parent[0].children[0].id == 1
 	assert parent[0].children[1].id == 2
 	assert parent[0].children.len == 2
+
+	db.close()!
 }
diff --git a/vlib/db/sqlite/sqlite_comptime_field_test.v b/vlib/db/sqlite/sqlite_comptime_field_test.v
index bbe5b33ae19770..eeb191d07c5322 100644
--- a/vlib/db/sqlite/sqlite_comptime_field_test.v
+++ b/vlib/db/sqlite/sqlite_comptime_field_test.v
@@ -22,7 +22,7 @@ fn records_by_field[T](db sqlite.DB, fieldname string, value string) ![]T {
 }
 
 fn test_main() {
-	db := sqlite.connect(':memory:')!
+	mut db := sqlite.connect(':memory:')!
 	sql db {
 		create table Blog
 	}!
@@ -40,4 +40,5 @@ fn test_main() {
 		return
 	}
 	assert rows.len == 1
+	db.close()!
 }
diff --git a/vlib/db/sqlite/sqlite_test.v b/vlib/db/sqlite/sqlite_test.v
index 7b334fd16f84bf..436ce50330ce0d 100644
--- a/vlib/db/sqlite/sqlite_test.v
+++ b/vlib/db/sqlite/sqlite_test.v
@@ -11,7 +11,7 @@ pub:
 type Content = []u8 | string
 
 struct Host {
-pub:
+pub mut:
 	db Connection
 }
 
@@ -92,7 +92,8 @@ fn test_can_access_sqlite_result_consts() {
 }
 
 fn test_alias_db() {
-	create_host(sqlite.connect(':memory:')!)!
+	mut host := create_host(sqlite.connect(':memory:')!)!
+	host.db.close()!
 	assert true
 }
 
@@ -110,7 +111,9 @@ fn test_exec_param_many() {
 		'Sam',
 	]) or {
 		assert err.code() == 19 // constraint failure
+		db.close()!
 		return
 	}
+	db.close()!
 	assert false
 }
diff --git a/vlib/json/cjson/cjson_test.v b/vlib/json/cjson/cjson_test.v
index f50c7131c87013..53e7e812a56716 100644
--- a/vlib/json/cjson/cjson_test.v
+++ b/vlib/json/cjson/cjson_test.v
@@ -5,6 +5,7 @@ fn test_object_with_null() {
 	root.add_item_to_object('name', cjson.create_string('Andre'))
 	root.add_item_to_object('age', cjson.create_null())
 	assert root.print_unformatted() == '{"name":"Andre","age":null}'
+	unsafe { cjson.delete(root) }
 }
 
 fn test_creating_complex_json() {
@@ -18,4 +19,5 @@ fn test_creating_complex_json() {
 	println(result)
 
 	assert result == '["user",{"username":"foo","password":"bar"}]'
+	unsafe { cjson.delete(root) }
 }
diff --git a/vlib/json/cjson/cjson_wrapper.c.v b/vlib/json/cjson/cjson_wrapper.c.v
index 640dae27a18323..0650da1f61ab1b 100644
--- a/vlib/json/cjson/cjson_wrapper.c.v
+++ b/vlib/json/cjson/cjson_wrapper.c.v
@@ -82,6 +82,8 @@ fn C.cJSON_Print(object &C.cJSON) &char
 
 fn C.cJSON_PrintUnformatted(object &C.cJSON) &char
 
+fn C.cJSON_free(voidptr)
+
 //
 
 // version returns the version of cJSON as a string
@@ -168,7 +170,9 @@ pub fn (mut obj Node) print() string {
 // print serialises the node to a string, without formatting its structure, so the resulting string is shorter/cheaper to transmit.
 pub fn (mut obj Node) print_unformatted() string {
 	mut s := C.cJSON_PrintUnformatted(obj)
-	return unsafe { tos3(s) }
+	ret := unsafe { tos_clone(&u8(s)) }
+	C.cJSON_free(s)
+	return ret
 }
 
 // str returns the unformatted serialisation to string of the given Node.
diff --git a/vlib/net/websocket/websocket_test.v b/vlib/net/websocket/websocket_test.v
index dcd14ffd87f169..82930b8efce4b8 100644
--- a/vlib/net/websocket/websocket_test.v
+++ b/vlib/net/websocket/websocket_test.v
@@ -3,6 +3,7 @@ import net
 import net.websocket
 import time
 
+@[heap]
 struct WebsocketTestResults {
 pub mut:
 	nr_messages      int
diff --git a/vlib/v/tests/fns/fn_literal_type_test.v b/vlib/v/tests/fns/fn_literal_type_test.v
index 54a7d4068370b9..10a9c0934725a3 100644
--- a/vlib/v/tests/fns/fn_literal_type_test.v
+++ b/vlib/v/tests/fns/fn_literal_type_test.v
@@ -10,7 +10,7 @@ const const_users_offset = 1
 const const_users_offset2 = 1
 
 fn test_orm() {
-	db := sqlite.connect(':memory:') or { panic(err) }
+	mut db := sqlite.connect(':memory:') or { panic(err) }
 
 	upper_1 := User{
 		name: 'Test'
@@ -31,4 +31,5 @@ fn test_orm() {
 	} or { panic(err) }
 
 	assert result[0].name == 'Test'
+	db.close()!
 }
diff --git a/vlib/v/tests/orm_sub_struct_test.v b/vlib/v/tests/orm_sub_struct_test.v
index b520074c2600c7..0b0769e0c8196f 100644
--- a/vlib/v/tests/orm_sub_struct_test.v
+++ b/vlib/v/tests/orm_sub_struct_test.v
@@ -11,7 +11,7 @@ struct SubStruct {
 }
 
 fn test_orm_sub_structs() {
-	db := sqlite.connect(':memory:') or { panic(err) }
+	mut db := sqlite.connect(':memory:') or { panic(err) }
 	sql db {
 		create table Upper
 	}!
@@ -34,4 +34,5 @@ fn test_orm_sub_structs() {
 	}!
 
 	assert uppers.first().sub.name == upper_1.sub.name
+	db.close()!
 }
diff --git a/vlib/v/tests/orm_table_name_test.v b/vlib/v/tests/orm_table_name_test.v
index faecad405781b1..5cb5e346a738b5 100644
--- a/vlib/v/tests/orm_table_name_test.v
+++ b/vlib/v/tests/orm_table_name_test.v
@@ -6,12 +6,14 @@ struct ORMTableSpecificName {
 }
 
 fn test_orm_table_name() {
-	db := sqlite.connect(':memory:') or { panic(err) }
+	mut db := sqlite.connect(':memory:') or { panic(err) }
 	r := sql db {
 		select from ORMTableSpecificName
 	} or {
+		db.close()!
 		assert true
 		return
 	}
+	db.close()!
 	assert false
 }
diff --git a/vlib/v/tests/sql_statement_inside_fn_call_test.v b/vlib/v/tests/sql_statement_inside_fn_call_test.v
index 19636bb874d2a4..fac27f9224f135 100644
--- a/vlib/v/tests/sql_statement_inside_fn_call_test.v
+++ b/vlib/v/tests/sql_statement_inside_fn_call_test.v
@@ -10,7 +10,7 @@ fn x(m Movie) int {
 }
 
 fn test_sql_statement_inside_fn_call() {
-	db := sqlite.connect(':memory:') or { panic('failed') }
+	mut db := sqlite.connect(':memory:') or { panic('failed') }
 	sql db {
 		create table Movie
 	}!
@@ -21,4 +21,5 @@ fn test_sql_statement_inside_fn_call() {
 	dump(x(sql db {
 		select from Movie where id == 1
 	}!.first()))
+	db.close()!
 }