feat: use build by default

cibuildwheel/ios.py

@@ -389,7 +389,7 @@ def build(options: Options, tmp_path: Path) -> None:
 
         for config in python_configurations:
             build_options = options.build_options(config.identifier)
-            build_frontend = build_options.build_frontend or BuildFrontendConfig("pip")
+            build_frontend = build_options.build_frontend or BuildFrontendConfig("build")
             # uv doesn't support iOS
             if build_frontend.name == "build[uv]":
                 msg = "uv doesn't support iOS"

cibuildwheel/linux.py

@@ -202,7 +202,7 @@ def build_in_container(
         log.build_start(config.identifier)
         local_identifier_tmp_dir = local_tmp_dir / config.identifier
         build_options = options.build_options(config.identifier)
-        build_frontend = build_options.build_frontend or BuildFrontendConfig("pip")
+        build_frontend = build_options.build_frontend or BuildFrontendConfig("build")
         use_uv = build_frontend.name == "build[uv]"
         pip = ["uv", "pip"] if use_uv else ["pip"]
 

cibuildwheel/macos.py

@@ -404,7 +404,7 @@ def build(options: Options, tmp_path: Path) -> None:
 
         for config in python_configurations:
             build_options = options.build_options(config.identifier)
-            build_frontend = build_options.build_frontend or BuildFrontendConfig("pip")
+            build_frontend = build_options.build_frontend or BuildFrontendConfig("build")
             use_uv = build_frontend.name == "build[uv]"
             uv_path = find_uv()
             if use_uv and uv_path is None:

cibuildwheel/windows.py

@@ -355,7 +355,7 @@ def build(options: Options, tmp_path: Path) -> None:
 
         for config in python_configurations:
             build_options = options.build_options(config.identifier)
-            build_frontend = build_options.build_frontend or BuildFrontendConfig("pip")
+            build_frontend = build_options.build_frontend or BuildFrontendConfig("build")
             use_uv = build_frontend.name == "build[uv]" and can_use_uv(config)
             log.build_start(config.identifier)
 

docs/options.md

@@ -649,7 +649,7 @@ This option can also be set using the [command-line option](#command-line)
 ## Build customization
 
 ### `CIBW_BUILD_FRONTEND` {: #build-frontend}
-> Set the tool to use to build, either "pip" (default for now), "build", or "build\[uv\]"
+> Set the tool to use to build, either "build" (default), "build/[uv/]", or "pip"
 
 Options:
 
@@ -658,8 +658,8 @@ Options:
 
 Default: `pip`
 
-Choose which build frontend to use. Can either be "pip", which will run
-`python -m pip wheel`, or "build", which will run `python -m build --wheel`.
+Choose which build frontend to use. Can either be "build", which will run
+`python -m build --wheel`, or "pip", which will run `python -m pip wheel`.
 
 You can also use "build\[uv\]", which will use an external [uv][] everywhere
 possible, both through `--installer=uv` passed to build, as well as when making

test/test_before_build.py

@@ -44,6 +44,10 @@ def test(tmp_path):
         """python -c "import sys; open('{project}/pythonversion_bb.txt', 'w').write(sys.version)" && """
         f'''python -c "import sys; open('{{project}}/pythonprefix_bb.txt', 'w').write({SYS_PREFIX})"'''
     )
+    frontend = "build"
+    if utils.platform != "pyodide":
+        before_build = f"python -m pip install setuptools && {before_build}"
+        frontend = f"{frontend};args: --no-isolation"
 
     # build the wheels
     actual_wheels = utils.cibuildwheel_run(
@@ -52,6 +56,7 @@ def test(tmp_path):
             # write python version information to a temporary file, this is
             # checked in setup.py
             "CIBW_BEFORE_BUILD": before_build,
+            "CIBW_BUILD_FRONTEND": frontend,
         },
     )