diff --git a/include/sentry.h b/include/sentry.h
index e83fb9006d..f8867c7048 100644
--- a/include/sentry.h
+++ b/include/sentry.h
@@ -1387,6 +1387,59 @@ SENTRY_EXPERIMENTAL_API sentry_value_t sentry_span_start_child(
  */
 SENTRY_EXPERIMENTAL_API void sentry_span_finish(
     sentry_value_t root_transaction, sentry_value_t span);
+
+/**
+ * Sets a tag on a transaction to the given string value.
+ *
+ * Tags longer than 200 bytes will be truncated.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_transaction_set_tag(
+    sentry_value_t transaction, const char *tag, const char *value);
+
+/**
+ * Removes a tag from a transaction.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_transaction_remove_tag(
+    sentry_value_t transaction, const char *tag);
+
+/**
+ * Sets the given key in a transaction's "data" section to the given value.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_transaction_set_data(
+    sentry_value_t transaction, const char *key, sentry_value_t value);
+
+/**
+ * Removes a key from a transaction's "data" section.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_transaction_remove_data(
+    sentry_value_t transaction, const char *key);
+
+/**
+ * Sets a tag on a span to the given string value.
+ *
+ * Tags longer than 200 bytes will be truncated.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_span_set_tag(
+    sentry_value_t span, const char *tag, const char *value);
+
+/**
+ * Removes a tag from a span.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_span_remove_tag(
+    sentry_value_t span, const char *tag);
+
+/**
+ * Sets the given key in a span's "data" section to the given value.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_span_set_data(
+    sentry_value_t span, const char *key, sentry_value_t value);
+
+/**
+ * Removes a key from a span's "data" section.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_span_remove_data(
+    sentry_value_t span, const char *key);
+
 #endif
 
 #ifdef __cplusplus
diff --git a/src/sentry_value.c b/src/sentry_value.c
index f4bf51f3db..7a22b91f94 100644
--- a/src/sentry_value.c
+++ b/src/sentry_value.c
@@ -1254,3 +1254,75 @@ sentry_event_value_add_stacktrace(sentry_value_t event, void **ips, size_t len)
 
     sentry_event_add_thread(event, thread);
 }
+
+void
+sentry_span_set_tag(sentry_value_t span, const char *tag, const char *value)
+{
+    sentry_value_t tags = sentry_value_get_by_key(span, "tags");
+    if (sentry_value_is_null(tags)) {
+        tags = sentry_value_new_object();
+        sentry_value_set_by_key(span, "tags", tags);
+    }
+
+    char *s = sentry__string_clonen(value, 200);
+    if (s) {
+        sentry_value_set_by_key(tags, tag, sentry__value_new_string_owned(s));
+    } else {
+        sentry_value_set_by_key(tags, tag, sentry_value_new_null());
+    }
+}
+
+void
+sentry_span_remove_tag(sentry_value_t span, const char *tag)
+{
+    sentry_value_t tags = sentry_value_get_by_key(span, "tags");
+    if (!sentry_value_is_null(tags)) {
+        sentry_value_remove_by_key(tags, tag);
+    }
+}
+
+void
+sentry_span_set_data(sentry_value_t span, const char *key, sentry_value_t value)
+{
+    sentry_value_t data = sentry_value_get_by_key(span, "data");
+    if (sentry_value_is_null(data)) {
+        data = sentry_value_new_object();
+        sentry_value_set_by_key(span, "data", data);
+    }
+    sentry_value_set_by_key(data, key, value);
+}
+
+void
+sentry_span_remove_data(sentry_value_t span, const char *key)
+{
+    sentry_value_t data = sentry_value_get_by_key(span, "data");
+    if (!sentry_value_is_null(data)) {
+        sentry_value_remove_by_key(data, key);
+    }
+}
+
+void
+sentry_transaction_set_tag(
+    sentry_value_t transaction, const char *tag, const char *value)
+{
+    sentry_span_set_tag(transaction, tag, value);
+}
+
+void
+sentry_transaction_remove_tag(sentry_value_t transaction, const char *tag)
+{
+    sentry_span_remove_tag(transaction, tag);
+}
+
+void
+sentry_transaction_set_data(
+    sentry_value_t transaction, const char *key, sentry_value_t value)
+{
+    sentry_span_set_data(transaction, key, value);
+}
+
+void
+sentry_transaction_remove_data(sentry_value_t transaction, const char *key)
+{
+    sentry_span_remove_data(transaction, key);
+}