diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ca414278f..00909a062 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -134,7 +134,7 @@ jobs:
 
       - name: Expose llvm PATH for Mac
         if: ${{ runner.os == 'macOS' }}
-        run: echo $(brew --prefix llvm@14)/bin >> $GITHUB_PATH
+        run: echo $(brew --prefix llvm@15)/bin >> $GITHUB_PATH
 
       - name: Installing Android SDK Dependencies
         if: ${{ env['ANDROID_API'] }}
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 20ae0d873..78b9c8269 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,7 @@
 
 **Fixes**:
 
+- Open the database file-lock on "UNIX" with `O_RDRW` ([#791](https://github.com/getsentry/sentry-native/pull/791))
 - Better error messages in `sentry_transport_curl`. ([#777](https://github.com/getsentry/sentry-native/pull/777))
 - Fix sporadic crash on Windows due to race condition when initializing background-worker thread-id. ([#785](https://github.com/getsentry/sentry-native/pull/785))
 - Increased curl headers buffer size to 512 (in `sentry_transport_curl`). ([#784](https://github.com/getsentry/sentry-native/pull/784))
diff --git a/src/path/sentry_path_unix.c b/src/path/sentry_path_unix.c
index 041a23b41..d75a0eb8f 100644
--- a/src/path/sentry_path_unix.c
+++ b/src/path/sentry_path_unix.c
@@ -54,15 +54,7 @@ sentry__filelock_try_lock(sentry_filelock_t *lock)
 {
     lock->is_locked = false;
 
-    const int oflags =
-#ifdef SENTRY_PLATFORM_AIX
-        // Under AIX, O_TRUNC can only be set if it can be written to, and
-        // flock (well, fcntl) will return EBADF if the fd is not read-write.
-        O_RDWR | O_CREAT | O_TRUNC;
-#else
-        O_RDONLY | O_CREAT | O_TRUNC;
-#endif
-    int fd = open(lock->path->path, oflags,
+    int fd = open(lock->path->path, O_RDWR | O_CREAT | O_TRUNC,
         S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
     if (fd < 0) {
         return false;
diff --git a/src/sentry_database.c b/src/sentry_database.c
index 62a619d8a..d9874fcdb 100644
--- a/src/sentry_database.c
+++ b/src/sentry_database.c
@@ -4,6 +4,7 @@
 #include "sentry_json.h"
 #include "sentry_options.h"
 #include "sentry_session.h"
+#include <errno.h>
 #include <string.h>
 
 sentry_run_t *
@@ -49,13 +50,20 @@ sentry__run_new(const sentry_path_t *database_path)
     run->run_path = run_path;
     run->session_path = session_path;
     run->lock = sentry__filelock_new(lock_path);
-    if (!run->lock || !sentry__filelock_try_lock(run->lock)) {
-        sentry__run_free(run);
-        return NULL;
+    if (!run->lock) {
+        goto error;
+    }
+    if (!sentry__filelock_try_lock(run->lock)) {
+        SENTRY_WARNF("failed to lock file \"%s\" (%s)", lock_path->path,
+            strerror(errno));
+        goto error;
     }
-
     sentry__path_create_dir_all(run->run_path);
     return run;
+
+error:
+    sentry__run_free(run);
+    return NULL;
 }
 
 void