diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 74ed3c4..ea338f2 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -21,7 +21,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php: [ '7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3', '8.4', '8.5' ]
+        php: [ '7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3', '8.4', '8.5', '8.6' ]
 
         name:
           - linux
diff --git a/tests/spx_auto_start_005.phpt b/tests/spx_auto_start_005.phpt
index 7e1b9b3..8957f08 100644
--- a/tests/spx_auto_start_005.phpt
+++ b/tests/spx_auto_start_005.phpt
@@ -1,5 +1,7 @@
 --TEST--
 Auto start disabled, full report & span report keys printed
+--INI--
+spx.data_dir="{PWD}/tmp_data_dir_auto_start_005"
 --ENV--
 return <<<END
 SPX_ENABLED=1
@@ -28,4 +30,10 @@ for ($i = 0; $i < 3; $i++) {
 --EXPECTF--
 spx-full-%s
 spx-full-%s
-spx-full-%s
\ No newline at end of file
+spx-full-%s
+--CLEAN--
+<?php
+
+exec(sprintf('rm -rf %s', escapeshellarg(__DIR__ . '/tmp_data_dir_auto_start_005')));
+
+?>
diff --git a/tests/spx_auto_start_007.phpt b/tests/spx_auto_start_007.phpt
index 06d6b95..a02626e 100644
--- a/tests/spx_auto_start_007.phpt
+++ b/tests/spx_auto_start_007.phpt
@@ -3,6 +3,7 @@ Auto start disabled, full report & span report keys printed
 --CGI--
 --INI--
 spx.debug=1
+spx.data_dir="{PWD}/tmp_data_dir_auto_start_007"
 spx.http_enabled=1
 spx.http_key="dev"
 spx.http_ip_whitelist="127.0.0.1"
@@ -33,4 +34,10 @@ for ($i = 0; $i < 3; $i++) {
 --EXPECTF--
 spx-full-%s
 spx-full-%s
-spx-full-%s
\ No newline at end of file
+spx-full-%s
+--CLEAN--
+<?php
+
+exec(sprintf('rm -rf %s', escapeshellarg(__DIR__ . '/tmp_data_dir_auto_start_007')));
+
+?>
diff --git a/tests/spx_full_report_custom_metadata.phpt b/tests/spx_full_report_custom_metadata.phpt
index 8b3bfe4..2f7e593 100644
--- a/tests/spx_full_report_custom_metadata.phpt
+++ b/tests/spx_full_report_custom_metadata.phpt
@@ -2,6 +2,7 @@
 "full" report custom metadata
 --INI--
 log_errors=on
+spx.data_dir="{PWD}/tmp_data_dir_full_report_custom_metadata"
 --ENV--
 return <<<END
 SPX_ENABLED=1
@@ -155,3 +156,9 @@ Notice: SPX: spx_profiler_full_report_set_custom_metadata_str(): too large $cust
     ,"zm"
   ]
 }
+--CLEAN--
+<?php
+
+exec(sprintf('rm -rf %s', escapeshellarg(__DIR__ . '/tmp_data_dir_full_report_custom_metadata')));
+
+?>
diff --git a/tests/spx_full_report_data.phpt b/tests/spx_full_report_data.phpt
index acc6f8d..bf9d1f4 100644
--- a/tests/spx_full_report_data.phpt
+++ b/tests/spx_full_report_data.phpt
@@ -1,5 +1,7 @@
 --TEST--
 "full" report data
+--INI--
+spx.data_dir="{PWD}/tmp_data_dir_full_report_data"
 --ENV--
 return <<<END
 SPX_ENABLED=1
@@ -78,3 +80,9 @@ b|2|%S|
 %s/tests/spx_full_report_data.php:9:foo
 %s/spx_full_report_data.php:5:bar
 %s/spx_full_report_data.php:2:baz
+--CLEAN--
+<?php
+
+exec(sprintf('rm -rf %s', escapeshellarg(__DIR__ . '/tmp_data_dir_full_report_data')));
+
+?>
diff --git a/tests/spx_ini_params_no_unnecessary_access_check.phpt b/tests/spx_ini_params_no_unnecessary_access_check.phpt
index 1eb57c7..17b7ec8 100644
--- a/tests/spx_ini_params_no_unnecessary_access_check.phpt
+++ b/tests/spx_ini_params_no_unnecessary_access_check.phpt
@@ -3,6 +3,7 @@ INI profiling parameters: no unnecessary access check (no related log expected)
 --CGI--
 --INI--
 spx.debug=1
+spx.data_dir="{PWD}/tmp_data_dir_ini_params_no_unnecessary_access_check"
 spx.http_profiling_enabled=1
 spx.http_enabled=1
 spx.http_key="dev"
@@ -16,3 +17,9 @@ echo 'Normal output';
 SPX-Debug-Profiling-Triggered: 1
 --EXPECT--
 Normal output
+--CLEAN--
+<?php
+
+exec(sprintf('rm -rf %s', escapeshellarg(__DIR__ . '/tmp_data_dir_ini_params_no_unnecessary_access_check')));
+
+?>
diff --git a/tests/spx_ini_params_not_overridden.phpt b/tests/spx_ini_params_not_overridden.phpt
index bc2ef40..a0c6e05 100644
--- a/tests/spx_ini_params_not_overridden.phpt
+++ b/tests/spx_ini_params_not_overridden.phpt
@@ -3,6 +3,7 @@ INI profiling parameters: not overridden by query string (bad auth)s
 --CGI--
 --INI--
 spx.debug=1
+spx.data_dir="{PWD}/tmp_data_dir_ini_params_not_overridden"
 spx.http_profiling_enabled=1
 spx.http_enabled=1
 spx.http_key="dev"
@@ -25,7 +26,6 @@ Normal output
 --CLEAN--
 <?php
 
-$data_dir = ini_get('spx.data_dir');
-exec(sprintf('rm -rf %s', escapeshellarg($data_dir)));
+exec(sprintf('rm -rf %s', escapeshellarg(__DIR__ . '/tmp_data_dir_ini_params_not_overridden')));
 
 ?>
diff --git a/tests/spx_ini_params_profiling_enabled.phpt b/tests/spx_ini_params_profiling_enabled.phpt
index 8dd42bd..7640588 100644
--- a/tests/spx_ini_params_profiling_enabled.phpt
+++ b/tests/spx_ini_params_profiling_enabled.phpt
@@ -3,6 +3,7 @@ INI profiling parameters: profiling enabled
 --CGI--
 --INI--
 spx.debug=1
+spx.data_dir="{PWD}/tmp_data_dir_ini_params_profiling_enabled"
 spx.http_profiling_enabled=1
 --FILE--
 <?php
@@ -15,7 +16,6 @@ Normal output
 --CLEAN--
 <?php
 
-$data_dir = ini_get('spx.data_dir');
-exec(sprintf('rm -rf %s', escapeshellarg($data_dir)));
+exec(sprintf('rm -rf %s', escapeshellarg(__DIR__ . '/tmp_data_dir_ini_params_profiling_enabled')));
 
 ?>
diff --git a/tests/spx_ui_report_delete_all.phpt b/tests/spx_ui_report_delete_all.phpt
index 3965081..99a0f66 100644
--- a/tests/spx_ui_report_delete_all.phpt
+++ b/tests/spx_ui_report_delete_all.phpt
@@ -4,7 +4,7 @@ UI: delete all reports
 spx.http_enabled=1
 spx.http_key="dev"
 spx.http_ip_whitelist="127.0.0.1"
-spx.data_dir="{PWD}/tmp_data_dir"
+spx.data_dir="{PWD}/tmp_data_dir_delete_all"
 log_errors=on
 --FILE--
 <?php
@@ -34,4 +34,4 @@ $clean();
 --EXPECTF--
 {"success": true}
 Remaining files:
-%s/tmp_data_dir/keep.txt
+%s/tmp_data_dir_delete_all/keep.txt
diff --git a/tests/spx_ui_report_delete_all_empty.phpt b/tests/spx_ui_report_delete_all_empty.phpt
index e4a07b2..797908f 100644
--- a/tests/spx_ui_report_delete_all_empty.phpt
+++ b/tests/spx_ui_report_delete_all_empty.phpt
@@ -4,7 +4,7 @@ UI: delete all reports (empty directory)
 spx.http_enabled=1
 spx.http_key="dev"
 spx.http_ip_whitelist="127.0.0.1"
-spx.data_dir="{PWD}/tmp_data_dir"
+spx.data_dir="{PWD}/tmp_data_dir_delete_all_empty"
 log_errors=on
 --FILE--
 <?php
diff --git a/tests/spx_ui_report_delete_confinement.phpt b/tests/spx_ui_report_delete_confinement.phpt
index f8e9539..cf642ca 100644
--- a/tests/spx_ui_report_delete_confinement.phpt
+++ b/tests/spx_ui_report_delete_confinement.phpt
@@ -4,7 +4,7 @@ UI: delete confinement check
 spx.http_enabled=1
 spx.http_key="dev"
 spx.http_ip_whitelist="127.0.0.1"
-spx.data_dir="{PWD}/tmp_data_dir"
+spx.data_dir="{PWD}/tmp_data_dir_delete_confinement"
 log_errors=on
 --FILE--
 <?php
diff --git a/tests/spx_ui_report_delete_nonexistent.phpt b/tests/spx_ui_report_delete_nonexistent.phpt
index 2784482..e8e8294 100644
--- a/tests/spx_ui_report_delete_nonexistent.phpt
+++ b/tests/spx_ui_report_delete_nonexistent.phpt
@@ -4,7 +4,7 @@ UI: delete non-existent report
 spx.http_enabled=1
 spx.http_key="dev"
 spx.http_ip_whitelist="127.0.0.1"
-spx.data_dir="{PWD}/tmp_data_dir"
+spx.data_dir="{PWD}/tmp_data_dir_delete_nonexistent"
 log_errors=on
 --FILE--
 <?php
diff --git a/tests/spx_ui_report_delete_one.phpt b/tests/spx_ui_report_delete_one.phpt
index ea8b093..c86b2b1 100644
--- a/tests/spx_ui_report_delete_one.phpt
+++ b/tests/spx_ui_report_delete_one.phpt
@@ -4,7 +4,7 @@ UI: delete foo report
 spx.http_enabled=1
 spx.http_key="dev"
 spx.http_ip_whitelist="127.0.0.1"
-spx.data_dir="{PWD}/tmp_data_dir"
+spx.data_dir="{PWD}/tmp_data_dir_delete_one"
 log_errors=on
 --FILE--
 <?php