diff --git a/.sg/rules/os-environ-usage.yml b/.sg/rules/os-environ-usage.yml
new file mode 100644
index 00000000000..df2c0386a67
--- /dev/null
+++ b/.sg/rules/os-environ-usage.yml
@@ -0,0 +1,93 @@
+id: os-environ-usage
+message: Use `ddtrace.settings._env` instead of `os` to access environment variables
+severity: error
+language: python
+files:
+  - "ddtrace/**"
+ignores:
+  - "ddtrace/settings/_env.py"
+rule:
+  any:
+    # Match os.environ access patterns
+    - pattern: os.environ
+    - pattern: os.environ[$$$ARGS]
+    - pattern: os.environ.get($$$ARGS)
+    - pattern: os.environ.keys($$$ARGS)
+    - pattern: os.environ.values($$$ARGS)
+    - pattern: os.environ.items($$$ARGS)
+    - pattern: os.environ.copy($$$ARGS)
+    - pattern: os.environ.clear($$$ARGS)
+    - pattern: os.environ.update($$$ARGS)
+    - pattern: os.environ.pop($$$ARGS)
+    - pattern: os.environ.setdefault($$$ARGS)
+
+    # Match os.getenv() calls
+    - pattern: os.getenv($$$ARGS)
+
+    # Match direct imports and usage of environ
+    - pattern: from os import environ
+    - pattern: from os import environ as $ALIAS
+    - pattern: from os import $$$IMPORTS, environ
+    - pattern: from os import $$$IMPORTS, environ as $ALIAS
+    - pattern: from os import environ, $$$IMPORTS
+    - pattern: from os import environ as $ALIAS, $$$IMPORTS
+
+    # Match direct imports and usage of getenv
+    - pattern: from os import getenv
+    - pattern: from os import getenv as $ALIAS
+    - pattern: from os import $$$IMPORTS, getenv
+    - pattern: from os import $$$IMPORTS, getenv as $ALIAS
+    - pattern: from os import getenv, $$$IMPORTS
+    - pattern: from os import getenv as $ALIAS, $$$IMPORTS
+
+    # Match usage of imported environ (direct name access)
+    - pattern: environ[$$$ARGS]
+      has:
+        kind: module
+        pattern: |
+          from os import environ
+    - pattern: environ.get($$$ARGS)
+      has:
+        kind: module
+        pattern: |
+          from os import environ
+    - pattern: environ.keys($$$ARGS)
+      has:
+        kind: module
+        pattern: |
+          from os import environ
+    - pattern: environ.values($$$ARGS)
+      has:
+        kind: module
+        pattern: |
+          from os import environ
+    - pattern: environ.items($$$ARGS)
+      has:
+        kind: module
+        pattern: |
+          from os import environ
+
+    # Match usage of imported getenv
+    - pattern: getenv($$$ARGS)
+      has:
+        kind: module
+        pattern: |
+          from os import getenv
+
+note: |
+  Direct access to os.environ or os.getenv is not allowed in this codebase.
+
+  Instead, use the centralized environment variable helper `ddtrace.settings._env`
+
+  Before:
+    import os
+    value = os.environ["HOME"]
+    debug = os.getenv("DEBUG", "false")
+
+  After:
+    from ddtrace.settings import _env
+    value = _env.environ["HOME"]
+    debug = _env.getenv("DEBUG", "false")
+
+  This ensures consistent environment variable handling across the codebase.
+
diff --git a/.sg/tests/__snapshots__/os-environ-usage-snapshot.yml b/.sg/tests/__snapshots__/os-environ-usage-snapshot.yml
new file mode 100644
index 00000000000..df11f9d9cf4
--- /dev/null
+++ b/.sg/tests/__snapshots__/os-environ-usage-snapshot.yml
@@ -0,0 +1,247 @@
+id: os-environ-usage
+snapshots:
+  from os import environ:
+    labels:
+    - source: from os import environ
+      style: primary
+      start: 0
+      end: 22
+  ? |
+    from os import environ
+    env_keys = environ.keys()
+  : labels:
+    - source: from os import environ
+      style: primary
+      start: 0
+      end: 22
+  ? |
+    from os import environ
+    value = environ.get("SHELL")
+  : labels:
+    - source: from os import environ
+      style: primary
+      start: 0
+      end: 22
+  ? |
+    from os import environ
+    value = environ["USER"]
+  : labels:
+    - source: from os import environ
+      style: primary
+      start: 0
+      end: 22
+  from os import environ as env_dict:
+    labels:
+    - source: from os import environ as env_dict
+      style: primary
+      start: 0
+      end: 34
+  ? |
+    from os import environ as env_dict
+    value = env_dict.get("PATH")
+  : labels:
+    - source: from os import environ as env_dict
+      style: primary
+      start: 0
+      end: 34
+  ? |
+    from os import environ as env_dict
+    value = env_dict["HOME"]
+  : labels:
+    - source: from os import environ as env_dict
+      style: primary
+      start: 0
+      end: 34
+  from os import environ, getenv:
+    labels:
+    - source: from os import environ, getenv
+      style: primary
+      start: 0
+      end: 30
+  from os import getenv:
+    labels:
+    - source: from os import getenv
+      style: primary
+      start: 0
+      end: 21
+  ? |
+    from os import getenv
+    value = getenv("CONFIG")
+  : labels:
+    - source: from os import getenv
+      style: primary
+      start: 0
+      end: 21
+  ? |
+    from os import getenv
+    value = getenv("MODE", "production")
+  : labels:
+    - source: from os import getenv
+      style: primary
+      start: 0
+      end: 21
+  from os import getenv as get_env_func:
+    labels:
+    - source: from os import getenv as get_env_func
+      style: primary
+      start: 0
+      end: 37
+  ? |
+    from os import getenv as get_env_func
+    value = get_env_func("LEVEL")
+  : labels:
+    - source: from os import getenv as get_env_func
+      style: primary
+      start: 0
+      end: 37
+  ? |
+    from os import getenv as get_env_func
+    value = get_env_func("PORT", "8080")
+  : labels:
+    - source: from os import getenv as get_env_func
+      style: primary
+      start: 0
+      end: 37
+  from os import getenv, environ:
+    labels:
+    - source: from os import getenv, environ
+      style: primary
+      start: 0
+      end: 30
+  from os import path, environ, getenv:
+    labels:
+    - source: from os import path, environ, getenv
+      style: primary
+      start: 0
+      end: 36
+  ? |
+    import os
+    all_items = os.environ.items()
+  : labels:
+    - source: os.environ.items()
+      style: primary
+      start: 22
+      end: 40
+  ? |
+    import os
+    all_keys = os.environ.keys()
+  : labels:
+    - source: os.environ.keys()
+      style: primary
+      start: 21
+      end: 38
+  ? |
+    import os
+    all_values = os.environ.values()
+  : labels:
+    - source: os.environ.values()
+      style: primary
+      start: 23
+      end: 42
+  ? |
+    import os
+    default_val = os.environ.setdefault("DEF", "default")
+  : labels:
+    - source: os.environ.setdefault("DEF", "default")
+      style: primary
+      start: 24
+      end: 63
+  ? |
+    import os
+    env_copy = os.environ.copy()
+  : labels:
+    - source: os.environ.copy()
+      style: primary
+      start: 21
+      end: 38
+  ? |
+    import os
+    env_ref = os.environ
+  : labels:
+    - source: os.environ
+      style: primary
+      start: 20
+      end: 30
+  ? |
+    import os
+    for k, v in os.environ.items():
+        pass
+  : labels:
+    - source: os.environ.items()
+      style: primary
+      start: 22
+      end: 40
+  ? |
+    import os
+    for key in os.environ:
+        pass
+  : labels:
+    - source: os.environ
+      style: primary
+      start: 21
+      end: 31
+  ? |
+    import os
+    if "HOME" in os.environ:
+        pass
+  : labels:
+    - source: os.environ
+      style: primary
+      start: 23
+      end: 33
+  ? |
+    import os
+    os.environ.clear()
+  : labels:
+    - source: os.environ.clear()
+      style: primary
+      start: 10
+      end: 28
+  ? |
+    import os
+    os.environ.update({"NEW_VAR": "value"})
+  : labels:
+    - source: 'os.environ.update({"NEW_VAR": "value"})'
+      style: primary
+      start: 10
+      end: 49
+  ? |
+    import os
+    removed = os.environ.pop("TEMP_VAR", None)
+  : labels:
+    - source: os.environ.pop("TEMP_VAR", None)
+      style: primary
+      start: 20
+      end: 52
+  ? |
+    import os
+    value = os.environ.get("PATH")
+  : labels:
+    - source: os.environ.get("PATH")
+      style: primary
+      start: 18
+      end: 40
+  ? |
+    import os
+    value = os.environ["HOME"]
+  : labels:
+    - source: os.environ["HOME"]
+      style: primary
+      start: 18
+      end: 36
+  ? |
+    import os
+    value = os.getenv("DEBUG")
+  : labels:
+    - source: os.getenv("DEBUG")
+      style: primary
+      start: 18
+      end: 36
+  ? |
+    import os
+    value = os.getenv("TIMEOUT", "30")
+  : labels:
+    - source: os.getenv("TIMEOUT", "30")
+      style: primary
+      start: 18
+      end: 44
diff --git a/.sg/tests/os-environ-usage-test.yml b/.sg/tests/os-environ-usage-test.yml
new file mode 100644
index 00000000000..85f2f42bb53
--- /dev/null
+++ b/.sg/tests/os-environ-usage-test.yml
@@ -0,0 +1,129 @@
+id: os-environ-usage
+valid:
+  # These should NOT trigger the rule (valid code)
+  - |
+    from ddtrace.setting import _env
+    debug = _env.getenv("DEBUG", "false")
+    value = _env.environ["HOME"]
+  - |
+    from ddtrace.settings._env import environ
+    value = environ["HOME"]
+  - |
+    from ddtrace.settings._env import getenv
+    debug = getenv("DEBUG", "false")
+  - |
+    from ddtrace.settings._env import environ, getenv
+    value = environ["HOME"]
+    debug = getenv("DEBUG", "false")
+  - |
+    # Using the centralized helpers is OK
+    from ddtrace.settings._env import environ
+    if "HOME" in environ:
+        print(environ["HOME"])
+
+invalid:
+  # These should trigger the rule (errors)
+
+  # Direct os.environ access patterns
+  - |
+    import os
+    value = os.environ["HOME"]
+  - |
+    import os
+    value = os.environ.get("PATH")
+  - |
+    import os
+    env_copy = os.environ.copy()
+  - |
+    import os
+    os.environ.clear()
+  - |
+    import os
+    os.environ.update({"NEW_VAR": "value"})
+  - |
+    import os
+    removed = os.environ.pop("TEMP_VAR", None)
+  - |
+    import os
+    default_val = os.environ.setdefault("DEF", "default")
+  - |
+    import os
+    all_keys = os.environ.keys()
+  - |
+    import os
+    all_values = os.environ.values()
+  - |
+    import os
+    all_items = os.environ.items()
+
+  # Membership tests and iteration
+  - |
+    import os
+    if "HOME" in os.environ:
+        pass
+  - |
+    import os
+    for key in os.environ:
+        pass
+  - |
+    import os
+    for k, v in os.environ.items():
+        pass
+
+  # os.getenv function calls
+  - |
+    import os
+    value = os.getenv("DEBUG")
+  - |
+    import os
+    value = os.getenv("TIMEOUT", "30")
+
+  # Direct environ usage (imported from os)
+  - from os import environ
+  - |
+    from os import environ
+    value = environ["USER"]
+  - |
+    from os import environ
+    value = environ.get("SHELL")
+  - |
+    from os import environ
+    env_keys = environ.keys()
+
+  # Aliased environ usage
+  - from os import environ as env_dict
+  - |
+    from os import environ as env_dict
+    value = env_dict["HOME"]
+  - |
+    from os import environ as env_dict
+    value = env_dict.get("PATH")
+
+  # Direct getenv calls (imported from os)
+  - from os import getenv
+  - |
+    from os import getenv
+    value = getenv("CONFIG")
+  - |
+    from os import getenv
+    value = getenv("MODE", "production")
+
+  # Aliased getenv calls
+  - from os import getenv as get_env_func
+  - |
+    from os import getenv as get_env_func
+    value = get_env_func("LEVEL")
+  - |
+    from os import getenv as get_env_func
+    value = get_env_func("PORT", "8080")
+
+  # Mixed imports
+  - from os import environ, getenv
+  - from os import getenv, environ
+  - from os import path, environ, getenv
+
+  # Direct attribute access
+  - |
+    import os
+    env_ref = os.environ
+