diff --git a/.github/workflows/workflow.yml b/.github/workflows/workflow.yml
index 0c62682..44246e3 100644
--- a/.github/workflows/workflow.yml
+++ b/.github/workflows/workflow.yml
@@ -15,5 +15,5 @@ jobs:
   ci:
     uses: community-of-python/community-workflow/.github/workflows/preset.yml@main
     with:
-      python-version: '["3.10","3.11","3.12","3.13", "3.14"]'
+      python-version: '["3.10","3.11","3.12","3.13", "3.14", "3.15"]'
     secrets: inherit
diff --git a/CLAUDE.md b/CLAUDE.md
index e396fe9..2381517 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -47,5 +47,5 @@ Microbootstrap auto-wires production instrumentation (observability, logging, tr
 ### Key constraints
 
 - Strict mypy — all code must type-check cleanly
-- Python 3.10–3.14 support required; avoid 3.11+ syntax
+- Python 3.10–3.15 support required; avoid 3.11+ syntax
 - All instrument extras are optional deps; use `TYPE_CHECKING` guards where needed
diff --git a/README.md b/README.md
index 9d7d444..3bbc73f 100644
--- a/README.md
+++ b/README.md
@@ -547,7 +547,7 @@ To integrate Pyroscope, specify the `pyroscope_endpoint`.
 
 When both Pyroscope and OpenTelemetry are enabled, profile span IDs will be included in traces using [`pyroscope-otel`](https://github.com/grafana/otel-profiling-python) for correlation.
 
-Note that Pyroscope integration is not supported on Windows.
+Note that Pyroscope integration is not supported on Windows and Python 3.15 yet.
 
 ### Logging
 
diff --git a/microbootstrap/helpers.py b/microbootstrap/helpers.py
index 1cae380..1164b25 100644
--- a/microbootstrap/helpers.py
+++ b/microbootstrap/helpers.py
@@ -1,7 +1,6 @@
 import dataclasses
 import re
 import typing
-from dataclasses import _MISSING_TYPE
 
 from microbootstrap import exceptions
 
@@ -20,10 +19,10 @@ def dataclass_to_dict_no_defaults(dataclass_to_convert: "_DataclassT") -> dict[s
     conversion_result: typing.Final = {}
     for dataclass_field in dataclasses.fields(dataclass_to_convert):
         value = getattr(dataclass_to_convert, dataclass_field.name)
-        if isinstance(dataclass_field.default, _MISSING_TYPE):
+        if dataclass_field.default is dataclasses.MISSING:
             conversion_result[dataclass_field.name] = value
             continue
-        if dataclass_field.default != value and isinstance(dataclass_field.default_factory, _MISSING_TYPE):
+        if dataclass_field.default != value and dataclass_field.default_factory is dataclasses.MISSING:
             conversion_result[dataclass_field.name] = value
             continue
         if value != dataclass_field.default and value != dataclass_field.default_factory():  # type: ignore[operator]
diff --git a/microbootstrap/instruments/pyroscope_instrument.py b/microbootstrap/instruments/pyroscope_instrument.py
index a2dc270..4d9ce66 100644
--- a/microbootstrap/instruments/pyroscope_instrument.py
+++ b/microbootstrap/instruments/pyroscope_instrument.py
@@ -9,7 +9,7 @@
 try:
     import pyroscope  # type: ignore[import-untyped]
 except ImportError:  # pragma: no cover
-    pyroscope = None  # Not supported on Windows
+    pyroscope = None  # Not supported on Windows and Python 3.15 yet
 
 
 class PyroscopeConfig(BaseInstrumentConfig):
diff --git a/pyproject.toml b/pyproject.toml
index b29a08d..c21c55c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,6 +30,7 @@ classifiers = [
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
     "Programming Language :: Python :: 3.14",
+    "Programming Language :: Python :: 3.15",
 ]
 dependencies = [
     "eval-type-backport>=0.2",
@@ -43,7 +44,7 @@ dependencies = [
     "rich>=13",
     "sentry-sdk>=2.7",
     "structlog>=24",
-    "pyroscope-io>=1.0.0; platform_system != 'Windows'",
+    "pyroscope-io>=1.0.0; platform_system != 'Windows' and python_version < '3.15'",
     "opentelemetry-distro[otlp]>=0.54b1",
     "opentelemetry-instrumentation-aio-pika>=0.54b1",
     "opentelemetry-instrumentation-aiohttp-client>=0.54b1",