diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 0e012b56b..b2cb1783b 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -116,7 +116,7 @@ jobs:
           source $CONDA/etc/profile.d/conda.sh
           conda activate constructor
           mkdir -p examples_artifacts/
-          python scripts/run_examples.py --keep-artifacts=examples_artifacts/
+          python -u scripts/run_examples.py --keep-artifacts=examples_artifacts/
       - name: Upload the example installers as artifacts
         if: github.event_name == 'pull_request' && matrix.pyver == '3.9'
         uses: actions/upload-artifact@v3
diff --git a/CONSTRUCT.md b/CONSTRUCT.md
index 0d0b3e493..0ec1ed1bd 100644
--- a/CONSTRUCT.md
+++ b/CONSTRUCT.md
@@ -557,8 +557,11 @@ Read notes about the particularities of Windows silent mode `/S` in the
 
 _required:_ no<br/>
 _type:_ boolean<br/>
-Check if the path where the distribution is installed contains spaces and show a warning
-if any spaces are found. Default is True. (Windows only).
+Check if the path where the distribution is installed contains spaces. Default is True.
+To allow installations with spaces, change to False. Note that:
+
+- A recent conda-standalone (>=22.11.1) or equivalent is needed for full support.
+- `conda` cannot be present in the `base` environment
 
 Read notes about the particularities of Windows silent mode `/S` in the
 `installer_type` documentation.
diff --git a/constructor/construct.py b/constructor/construct.py
index 0bd1a7f36..e37b77eb0 100644
--- a/constructor/construct.py
+++ b/constructor/construct.py
@@ -444,8 +444,11 @@
 '''),
 
     ('check_path_spaces',     False, bool, '''
-Check if the path where the distribution is installed contains spaces and show a warning
-if any spaces are found. Default is True. (Windows only).
+Check if the path where the distribution is installed contains spaces. Default is True.
+To allow installations with spaces, change to False. Note that:
+
+- A recent conda-standalone (>=22.11.1) or equivalent is needed for full support.
+- `conda` cannot be present in the `base` environment
 
 Read notes about the particularities of Windows silent mode `/S` in the
 `installer_type` documentation.
diff --git a/constructor/fcp.py b/constructor/fcp.py
index b1f834e13..737e9fc51 100644
--- a/constructor/fcp.py
+++ b/constructor/fcp.py
@@ -367,19 +367,28 @@ def _fetch_precs(precs, download_dir, transmute_file_type=''):
 def _main(name, version, download_dir, platform, channel_urls=(), channels_remap=(), specs=(),
           exclude=(), menu_packages=(), ignore_duplicate_files=True, environment=None,
           environment_file=None, verbose=True, dry_run=False, conda_exe="conda.exe",
-          transmute_file_type='', extra_envs=None):
+          transmute_file_type='', extra_envs=None, check_path_spaces=True):
     precs = _solve_precs(
         name, version, download_dir, platform, channel_urls=channel_urls,
         channels_remap=channels_remap, specs=specs, exclude=exclude,
         menu_packages=menu_packages, environment=environment,
         environment_file=environment_file, verbose=verbose, conda_exe=conda_exe
     )
+    extra_envs = extra_envs or {}
+    conda_in_base: PackageCacheRecord = next((prec for prec in precs if prec.name == "conda"), None)
+    if conda_in_base:
+        if not check_path_spaces and platform.startswith(("linux-", "osx-")):
+            raise RuntimeError(
+                "'check_path_spaces=False' cannot be used on Linux and macOS installers "
+                "if 'conda' is present in the 'base' environment."
+            )
+    elif extra_envs:
+        raise RuntimeError(
+            "conda needs to be present in 'base' environment for 'extra_envs' to work"
+        )
 
     extra_envs_precs = {}
-    for env_name, env_config in (extra_envs or {}).items():
-        if not any(prec.name == "conda" for prec in precs):
-            raise RuntimeError("conda needs to be present in `base` environment for extra_envs to work")
-
+    for env_name, env_config in extra_envs.items():
         if verbose:
             print("Solving extra environment:", env_name)
         extra_envs_precs[env_name] = _solve_precs(
@@ -445,6 +454,7 @@ def main(info, verbose=True, dry_run=False, conda_exe="conda.exe"):
     environment_file = info.get("environment_file", None)
     transmute_file_type = info.get("transmute_file_type", "")
     extra_envs = info.get("extra_envs", {})
+    check_path_spaces = info.get("check_path_spaces", True)
 
     if not channel_urls and not channels_remap:
         sys.exit("Error: at least one entry in 'channels' or 'channels_remap' is required")
@@ -467,7 +477,7 @@ def main(info, verbose=True, dry_run=False, conda_exe="conda.exe"):
         has_conda, extra_envs_info) = _main(
             name, version, download_dir, platform, channel_urls, channels_remap, specs,
             exclude, menu_packages, ignore_duplicate_files, environment, environment_file,
-            verbose, dry_run, conda_exe, transmute_file_type, extra_envs
+            verbose, dry_run, conda_exe, transmute_file_type, extra_envs, check_path_spaces
         )
 
     info["_all_pkg_records"] = pkg_records  # full PackageRecord objects
diff --git a/constructor/header.sh b/constructor/header.sh
index 87ea8e489..b5d8859d9 100644
--- a/constructor/header.sh
+++ b/constructor/header.sh
@@ -27,7 +27,7 @@ export INSTALLER_TYPE="SH"
 THIS_DIR=$(DIRNAME=$(dirname "$0"); cd "$DIRNAME"; pwd)
 THIS_FILE=$(basename "$0")
 THIS_PATH="$THIS_DIR/$THIS_FILE"
-PREFIX=__DEFAULT_PREFIX__
+PREFIX="__DEFAULT_PREFIX__"
 #if batch_mode
 BATCH=1
 #else
@@ -58,7 +58,11 @@ Installs __NAME__ __VERSION__
 #if not keep_pkgs
 -k           do not clear the package cache after installation
 #endif
+#if check_path_spaces
 -p PREFIX    install prefix, defaults to $PREFIX, must not contain spaces.
+#else
+-p PREFIX    install prefix, defaults to $PREFIX
+#endif
 -s           skip running pre/post-link/install scripts
 -u           update an existing installation
 #if has_conda
@@ -66,106 +70,48 @@ Installs __NAME__ __VERSION__
 #endif
 "
 
-if which getopt > /dev/null 2>&1; then
-    OPTS=$(getopt bifhkp:sut "$*" 2>/dev/null)
-    if [ ! $? ]; then
-        printf "%s\\n" "$USAGE"
-        exit 2
-    fi
-
-    eval set -- "$OPTS"
-
-    while true; do
-        case "$1" in
-            -h)
-                printf "%s\\n" "$USAGE"
-                exit 2
-                ;;
-            -b)
-                BATCH=1
-                shift
-                ;;
-            -i)
-                BATCH=0
-                shift
-                ;;
-            -f)
-                FORCE=1
-                shift
-                ;;
-            -k)
-                KEEP_PKGS=1
-                shift
-                ;;
-            -p)
-                PREFIX="$2"
-                shift
-                shift
-                ;;
-            -s)
-                SKIP_SCRIPTS=1
-                shift
-                ;;
-            -u)
-                FORCE=1
-                shift
-                ;;
-#if has_conda
-            -t)
-                TEST=1
-                shift
-                ;;
-#endif
-            --)
-                shift
-                break
-                ;;
-            *)
-                printf "ERROR: did not recognize option '%s', please try -h\\n" "$1"
-                exit 1
-                ;;
-        esac
-    done
-else
-    while getopts "bifhkp:sut" x; do
-        case "$x" in
-            h)
-                printf "%s\\n" "$USAGE"
-                exit 2
+# We used to have a getopt version here, falling back to getopts if needed
+# However getopt is not standardized and the version on Mac has different
+# behaviour. getopts is good enough for what we need :)
+# More info: https://unix.stackexchange.com/questions/62950/
+while getopts "bifhkp:sut" x; do
+    case "$x" in
+        h)
+            printf "%s\\n" "$USAGE"
+            exit 2
+        ;;
+        b)
+            BATCH=1
+            ;;
+        i)
+            BATCH=0
+            ;;
+        f)
+            FORCE=1
+            ;;
+        k)
+            KEEP_PKGS=1
+            ;;
+        p)
+            PREFIX="$OPTARG"
+            ;;
+        s)
+            SKIP_SCRIPTS=1
+            ;;
+        u)
+            FORCE=1
             ;;
-            b)
-                BATCH=1
-                ;;
-            i)
-                BATCH=0
-                ;;
-            f)
-                FORCE=1
-                ;;
-            k)
-                KEEP_PKGS=1
-                ;;
-            p)
-                PREFIX="$OPTARG"
-                ;;
-            s)
-                SKIP_SCRIPTS=1
-                ;;
-            u)
-                FORCE=1
-                ;;
 #if has_conda
-            t)
-                TEST=1
-                ;;
+        t)
+            TEST=1
+            ;;
 #endif
-            ?)
-                printf "ERROR: did not recognize option '%s', please try -h\\n" "$x"
-                exit 1
-                ;;
-        esac
-    done
-fi
+        ?)
+            printf "ERROR: did not recognize option '%s', please try -h\\n" "$x"
+            exit 1
+            ;;
+    esac
+done
 
 # For testing, keep the package cache around longer
 CLEAR_AFTER_TEST=0
@@ -343,6 +289,7 @@ EOF
     printf "[%s] >>> " "$PREFIX"
     read -r user_prefix
     if [ "$user_prefix" != "" ]; then
+#if check_path_spaces is True
         case "$user_prefix" in
             *\ * )
                 printf "ERROR: Cannot install into directories with spaces\\n" >&2
@@ -352,15 +299,20 @@ EOF
                 eval PREFIX="$user_prefix"
                 ;;
         esac
+#else
+        PREFIX="$user_prefix"
+#endif
     fi
 fi # !BATCH
 
+#if check_path_spaces is True
 case "$PREFIX" in
     *\ * )
         printf "ERROR: Cannot install into directories with spaces\\n" >&2
         exit 1
         ;;
 esac
+#endif
 
 if [ "$FORCE" = "0" ] && [ -e "$PREFIX" ]; then
     printf "ERROR: File or directory already exists: '%s'\\n" "$PREFIX" >&2
@@ -370,7 +322,6 @@ elif [ "$FORCE" = "1" ] && [ -e "$PREFIX" ]; then
     REINSTALL=1
 fi
 
-
 if ! mkdir -p "$PREFIX"; then
     printf "ERROR: Could not create directory: '%s'\\n" "$PREFIX" >&2
     exit 1
@@ -438,8 +389,8 @@ extract_range $boundary0 $boundary1 > "$CONDA_EXEC"
 chmod +x "$CONDA_EXEC"
 
 export TMP_BACKUP="$TMP"
-export TMP=$PREFIX/install_tmp
-mkdir -p $TMP
+export TMP="$PREFIX/install_tmp"
+mkdir -p "$TMP"
 
 # the second binary payload: the tarball of packages
 printf "Unpacking payload ...\n"
@@ -473,7 +424,6 @@ else
 fi
 #endif
 
-PYTHON="$PREFIX/bin/python"
 MSGS="$PREFIX/.messages.txt"
 touch "$MSGS"
 export FORCE
@@ -494,9 +444,9 @@ CONDA_PKGS_DIRS="$PREFIX/pkgs" \
 rm -f "$PREFIX/pkgs/env.txt"
 
 #if has_conda
-mkdir -p $PREFIX/envs
-for env_pkgs in ${PREFIX}/pkgs/envs/*/; do
-    env_name=$(basename ${env_pkgs})
+mkdir -p "$PREFIX/envs"
+for env_pkgs in "${PREFIX}"/pkgs/envs/*/; do
+    env_name=$(basename "${env_pkgs}")
     if [ "$env_name" = "*" ]; then
         continue
     fi
@@ -526,9 +476,9 @@ POSTCONDA="$PREFIX/postconda.tar.bz2"
 "$CONDA_EXEC" constructor --prefix "$PREFIX" --extract-tarball < "$POSTCONDA" || exit 1
 rm -f "$POSTCONDA"
 
-rm -f $PREFIX/conda.exe
+rm -f "$CONDA_EXEC"
 
-rm -rf $PREFIX/install_tmp
+rm -rf "$PREFIX/install_tmp"
 export TMP="$TMP_BACKUP"
 
 
@@ -560,7 +510,7 @@ if [ "$KEEP_PKGS" = "0" ]; then
 else
     # Attempt to delete the empty temporary directories in the package cache
     # These are artifacts of the constructor --extract-conda-pkgs
-    find $PREFIX/pkgs -type d -empty -exec rmdir {} \; 2>/dev/null || :
+    find "$PREFIX/pkgs" -type d -empty -exec rmdir {} \; 2>/dev/null || :
 fi
 
 cat <<EOF
@@ -609,13 +559,15 @@ if [ "$BATCH" = "0" ]; then
         printf "\\n"
     else
         case $SHELL in
-            *zsh) $PREFIX/bin/conda init zsh ;;
-            *) $PREFIX/bin/conda init ;;
+            # We call the module directly to avoid issues with spaces in shebang
+            *zsh) "$PREFIX/bin/python" -m conda init zsh ;;
+            *) "$PREFIX/bin/python" -m conda init ;;
         esac
         if [ -f "$PREFIX/bin/mamba" ]; then
             case $SHELL in
-                *zsh) $PREFIX/bin/mamba init zsh ;;
-                *) $PREFIX/bin/mamba init ;;
+                # We call the module directly to avoid issues with spaces in shebang
+                *zsh) "$PREFIX/bin/python" -m mamba.mamba init zsh ;;
+                *) "$PREFIX/bin/python" -m mamba.mamba init ;;
             esac
         fi
     fi
diff --git a/constructor/osx/checks_before_install.sh b/constructor/osx/checks_before_install.sh
index 3eacf26e1..ef3555181 100644
--- a/constructor/osx/checks_before_install.sh
+++ b/constructor/osx/checks_before_install.sh
@@ -18,7 +18,6 @@ if [[ -e "$PREFIX" ]]; then
     # By default, osascript doesn't allow user interaction, so we have to work
     # around it.  http://stackoverflow.com/a/11874852/161801
     logger -p "install.info" "ERROR: __PATH_EXISTS_ERROR_TEXT__" || echo "ERROR: __PATH_EXISTS_ERROR_TEXT__"
-
     (osascript -e "try
 tell application (path to frontmost application as text)
 set theAlertText to \"Chosen path already exists!\"
@@ -31,10 +30,12 @@ end")
     exit 1
 fi
 
+#if check_path_spaces is True
 # Check if the path has spaces
 case "$PREFIX" in
-     *\ * )
-           (osascript -e "try
+    *\ * )
+        logger -p "install.info" "ERROR: '$PREFIX' contains spaces!" || echo "ERROR: '$PREFIX' contains spaces!"
+        (osascript -e "try
 tell application (path to frontmost application as text)
 set theAlertText to \"Chosen path contain spaces!\"
 set theAlertMessage to \"'$PREFIX' contains spaces. Please, relaunch the installer and choose another location in the Destination Select step.\"
@@ -43,11 +44,12 @@ end
 activate app (path to frontmost application as text)
 answer
 end")
-           exit 1
-          ;;
-       *)
+        exit 1
+        ;;
+    *)
 
-           ;;
+        ;;
 esac
+#endif
 
 exit 0
diff --git a/constructor/osx/prepare_installation.sh b/constructor/osx/prepare_installation.sh
index c80217fdb..f2b32ca6e 100644
--- a/constructor/osx/prepare_installation.sh
+++ b/constructor/osx/prepare_installation.sh
@@ -25,8 +25,8 @@ CONDA_EXEC="$PREFIX/conda.exe"
 chmod +x "$CONDA_EXEC"
 
 # Create a blank history file so conda thinks this is an existing env
-mkdir -p $PREFIX/conda-meta
-touch $PREFIX/conda-meta/history
+mkdir -p "$PREFIX/conda-meta"
+touch "$PREFIX/conda-meta/history"
 
 # Extract the conda packages but avoiding the overwriting of the
 # custom metadata we have already put in place
diff --git a/constructor/osx/run_installation.sh b/constructor/osx/run_installation.sh
index 4ad3d49c7..61b9ec532 100644
--- a/constructor/osx/run_installation.sh
+++ b/constructor/osx/run_installation.sh
@@ -40,10 +40,10 @@ rm -f "$PREFIX/env.txt"
 
 # Same, but for the extra environments
 
-mkdir -p $PREFIX/envs
+mkdir -p "$PREFIX/envs"
 
-for env_pkgs in ${PREFIX}/pkgs/envs/*/; do
-    env_name=$(basename ${env_pkgs})
+for env_pkgs in "${PREFIX}"/pkgs/envs/*/; do
+    env_name="$(basename "${env_pkgs}")"
     if [[ "${env_name}" == "*" ]]; then
         continue
     fi
@@ -53,10 +53,10 @@ for env_pkgs in ${PREFIX}/pkgs/envs/*/; do
     touch "$PREFIX/envs/$env_name/conda-meta/history"
 
     if [[ -f "${env_pkgs}channels.txt" ]]; then
-        env_channels=$(cat "${env_pkgs}channels.txt")
+        env_channels="$(cat "${env_pkgs}channels.txt")"
         rm -f "${env_pkgs}channels.txt"
     else
-        env_channels=__CHANNELS__
+        env_channels="__CHANNELS__"
     fi
     # TODO: custom channels per env?
     # TODO: custom shortcuts per env?
@@ -84,7 +84,7 @@ fi
 
 # This is unneeded for the default install to ~, but if the user changes the
 # install location, the permissions will default to root unless this is done.
-chown -R $USER "$PREFIX"
+chown -R "$USER" "$PREFIX"
 
 notify "Done! Installation is available in $PREFIX."
 
diff --git a/constructor/osx/update_path.sh b/constructor/osx/update_path.sh
index 7b24ebf53..8c2cf0d7a 100644
--- a/constructor/osx/update_path.sh
+++ b/constructor/osx/update_path.sh
@@ -7,4 +7,4 @@
 set -x
 PREFIX="$2/__NAME_LOWER__"
 PREFIX=$(cd "$PREFIX"; pwd)
-"$PREFIX/bin/conda" init --all
+"$PREFIX/bin/python" -m conda init --all
diff --git a/constructor/osxpkg.py b/constructor/osxpkg.py
index 829ee073d..eaee55d23 100644
--- a/constructor/osxpkg.py
+++ b/constructor/osxpkg.py
@@ -1,4 +1,5 @@
 import os
+import sys
 import shutil
 from os.path import isdir, abspath, dirname, exists, join
 from subprocess import check_call
@@ -8,9 +9,17 @@
 from tempfile import NamedTemporaryFile
 from textwrap import dedent
 
-import constructor.preconda as preconda
-from constructor.imaging import write_images
-from constructor.utils import add_condarc, get_final_channels, rm_rf, approx_size_kb
+from . import preconda
+from .construct import ns_platform
+from .imaging import write_images
+from .utils import (
+    add_condarc,
+    get_final_channels,
+    rm_rf,
+    approx_size_kb,
+    preprocess,
+    fill_template,
+)
 
 
 OSX_DIR = join(dirname(__file__), "osx")
@@ -246,24 +255,16 @@ def move_script(src, dst, info, ensure_shebang=False, user_script_type=None):
     Fill template scripts checks_before_install.sh, prepare_installation.sh and others,
     and move them to the installer workspace.
     """
+    assert user_script_type in (None, "pre_install", "post_install")
     with open(src) as fi:
         data = fi.read()
-
+    
+    # ppd hosts the conditions for the #if/#else/#endif preprocessors on scripts
+    ppd = ns_platform(info['_platform'])
+    ppd['check_path_spaces'] = bool(info.get("check_path_spaces", True))
+    
     # This is necessary for when installing on case-sensitive macOS filesystems.
     pkg_name_lower = info.get("pkg_name", info['name']).lower()
-    data = data.replace('__NAME_LOWER__', pkg_name_lower)
-    data = data.replace('__VERSION__', info['version'])
-    data = data.replace('__NAME__', info['name'])
-    data = data.replace('__CHANNELS__', ','.join(get_final_channels(info)))
-    data = data.replace('__WRITE_CONDARC__', '\n'.join(add_condarc(info)))
-    data = data.replace('__PLAT__', info['_platform'])
-    data = data.replace('__PROGRESS_NOTIFICATIONS__', str(info.get('progress_notifications')))
-    # Is this a user-provided script?
-    if user_script_type == "pre_install":
-        data = data.replace('__PRE_OR_POST__', "pre_install")
-    elif user_script_type == "post_install":
-        data = data.replace('__PRE_OR_POST__', "post_install")
-
     default_path_exists_error_text = (
         "'{CHOSEN_PATH}' already exists. Please, relaunch the installer and "
         "choose another location in the Destination Select step."
@@ -271,7 +272,19 @@ def move_script(src, dst, info, ensure_shebang=False, user_script_type=None):
     path_exists_error_text = info.get(
         "install_path_exists_error_text", default_path_exists_error_text
     ).format(CHOSEN_PATH=f"$2/{pkg_name_lower}")
-    data = data.replace('__PATH_EXISTS_ERROR_TEXT__', path_exists_error_text)
+    replace = {
+        'NAME': info['name'],
+        'NAME_LOWER': pkg_name_lower,
+        'VERSION': info['version'],
+        'PLAT': info['_platform'],
+        'CHANNELS': ','.join(get_final_channels(info)),
+        'WRITE_CONDARC': '\n'.join(add_condarc(info)),
+        'PATH_EXISTS_ERROR_TEXT': path_exists_error_text,
+        'PROGRESS_NOTIFICATIONS': str(info.get('progress_notifications', False)),
+        'PRE_OR_POST': user_script_type or '__PRE_OR_POST__',
+    }
+    data = preprocess(data, ppd)
+    data = fill_template(data, replace)
 
     with open(dst, 'w') as fo:
         if (
@@ -359,6 +372,16 @@ def pkgbuild_script(name, info, src, dst='postinstall', **kwargs):
 
 
 def create(info, verbose=False):
+    # Do some configuration checks
+    if info.get("check_path_spaces", True) is True:
+        for key in "default_location_pkg", "pkg_name":
+            if " " in info.get(key, ""):
+                sys.exit(
+                    f"ERROR: 'check_path_spaces' is enabled, but '{key}' "
+                    "contains spaces. This will always result in a failed "
+                    "installation! Aborting!"
+                )
+
     global CACHE_DIR, PACKAGE_ROOT, PACKAGES_DIR, SCRIPTS_DIR
 
     CACHE_DIR = info['_download_dir']
diff --git a/constructor/shar.py b/constructor/shar.py
index 27627febd..691535b53 100644
--- a/constructor/shar.py
+++ b/constructor/shar.py
@@ -59,6 +59,7 @@ def get_header(conda_exec, tarball, info):
     ppd['initialize_conda'] = info.get('initialize_conda', True)
     ppd['initialize_by_default'] = info.get('initialize_by_default', None)
     ppd['has_conda'] = info['_has_conda']
+    ppd['check_path_spaces'] = info.get("check_path_spaces", True)
     install_lines = list(add_condarc(info))
     # Needs to happen first -- can be templated
     replace = {
diff --git a/constructor/utils.py b/constructor/utils.py
index 117b624bf..14790cadc 100644
--- a/constructor/utils.py
+++ b/constructor/utils.py
@@ -117,7 +117,7 @@ def add_condarc(info):
             yield 'FileWrite $CONDARC "%s$\\r$\\n"' % line
         yield 'FileClose $CONDARC'
     else:
-        yield 'cat <<EOF >$PREFIX/.condarc'
+        yield 'cat <<EOF >"$PREFIX/.condarc"'
         for line in condarc.splitlines():
             yield line
         yield 'EOF'
diff --git a/examples/extra_envs/construct.yaml b/examples/extra_envs/construct.yaml
index a10da6117..ecec305e4 100644
--- a/examples/extra_envs/construct.yaml
+++ b/examples/extra_envs/construct.yaml
@@ -4,15 +4,15 @@ installer_type: all
 channels:
   - http://repo.anaconda.com/pkgs/main/
 specs:
-  - python=3.7
+  - python=3.9
   - conda # conda is required for extra_envs
   - console_shortcut # [win]
 exclude:  # [unix]
   - tk  # [unix]
 extra_envs:
-  py38:
+  py310:
     specs:
-      - python=3.8
+      - python=3.10
       - pip
     channels:
       - conda-forge
@@ -27,5 +27,5 @@ build_outputs:
   - info.json
   - pkgs_list
   - pkgs_list:
-      env: py38
+      env: py310
   - licenses
diff --git a/examples/extra_envs/test_install.bat b/examples/extra_envs/test_install.bat
index 2d70efb1a..3e90cc473 100644
--- a/examples/extra_envs/test_install.bat
+++ b/examples/extra_envs/test_install.bat
@@ -1,10 +1,10 @@
-:: base env
+:: base env has python 3.9
 if not exist "%PREFIX%\conda-meta\history" exit 1
-"%PREFIX%\python.exe" -c "from sys import version_info; assert version_info[:2] == (3, 7)" || goto :error
+"%PREFIX%\python.exe" -c "from sys import version_info; assert version_info[:2] == (3, 9)" || goto :error
 
-:: extra env named 'py38'
-if not exist "%PREFIX%\envs\py38\conda-meta\history" exit 1
-"%PREFIX%\envs\py38\python.exe" -c "from sys import version_info; assert version_info[:2] == (3, 8)" || goto :error
+:: extra env named 'py310' has python 3.10
+if not exist "%PREFIX%\envs\py310\conda-meta\history" exit 1
+"%PREFIX%\envs\py310\python.exe" -c "from sys import version_info; assert version_info[:2] == (3, 10)" || goto :error
 
 :: extra env named 'dav1d' only contains dav1d, no python
 if not exist "%PREFIX%\envs\dav1d\conda-meta\history" exit 1
diff --git a/examples/extra_envs/test_install.sh b/examples/extra_envs/test_install.sh
index 58544320b..a024c1d3e 100644
--- a/examples/extra_envs/test_install.sh
+++ b/examples/extra_envs/test_install.sh
@@ -2,20 +2,24 @@
 set -ex
 
 # tests
-# base environment uses python 3.7 and excludes tk
+# base environment uses python 3.9 and excludes tk
 test -f "$PREFIX/conda-meta/history"
-"$PREFIX/bin/python" -c "from sys import version_info; assert version_info[:2] == (3, 7)"
-"$PREFIX/bin/pip" -V
+"$PREFIX/bin/python" -c "from sys import version_info; assert version_info[:2] == (3, 9)"
+# we use python -m pip instead of the pip entry point
+# because the spaces break the shebang - this will be fixed
+# with a new conda release, but for now this is the workaround
+# we need. same with conda in the block below!
+"$PREFIX/bin/python" -m pip -V
 # tk(inter) shouldn't be listed by conda!
-"$PREFIX/bin/conda" list -p "$PREFIX" | jq -e '.[] | select(.name == "tk")' && exit 1
+"$PREFIX/bin/python" -m conda list -p "$PREFIX" | jq -e '.[] | select(.name == "tk")' && exit 1
 echo "Previous test failed as expected"
 
-# extra env named 'py38' uses python 3.8, has tk, but we removed setuptools
-test -f "$PREFIX/envs/py38/conda-meta/history"
-"$PREFIX/envs/py38/bin/python" -c "from sys import version_info; assert version_info[:2] == (3, 8)"
+# extra env named 'py310' uses python 3.10, has tk, but we removed setuptools
+test -f "$PREFIX/envs/py310/conda-meta/history"
+"$PREFIX/envs/py310/bin/python" -c "from sys import version_info; assert version_info[:2] == (3, 10)"
 # setuptools shouldn't be listed by conda!
-"$PREFIX/bin/conda" list -p "$PREFIX/envs/py38" | jq -e '.[] | select(.name == "setuptools")' && exit 1
-"$PREFIX/envs/py38/bin/python" -c "import setuptools" && exit 1
+"$PREFIX/bin/python" -m conda list -p "$PREFIX/envs/py310" | jq -e '.[] | select(.name == "setuptools")' && exit 1
+"$PREFIX/envs/py310/bin/python" -c "import setuptools" && exit 1
 echo "Previous test failed as expected"
 
 # this env only contains dav1d, no python; it should have been created with no errors,
diff --git a/examples/extra_files/construct.yaml b/examples/extra_files/construct.yaml
index 80cc1fc5b..1d248235e 100644
--- a/examples/extra_files/construct.yaml
+++ b/examples/extra_files/construct.yaml
@@ -1,6 +1,8 @@
 name: ExtraFiles
 version: X
 installer_type: all
+check_path_spaces: False
+check_path_length: False
 channels:
   - http://repo.anaconda.com/pkgs/main/
 specs:
diff --git a/examples/grin/construct.yaml b/examples/grin/construct.yaml
index 5b70d958b..2bb45f6aa 100644
--- a/examples/grin/construct.yaml
+++ b/examples/grin/construct.yaml
@@ -58,3 +58,6 @@ license_file: eula.txt
 #header_image_text:  |-
 #                    multi-line
 #                    header-text
+
+check_path_spaces: False
+check_path_length: False
diff --git a/examples/newchan/construct.yaml b/examples/newchan/construct.yaml
index 622d0fe04..05a1b668b 100644
--- a/examples/newchan/construct.yaml
+++ b/examples/newchan/construct.yaml
@@ -13,3 +13,5 @@ specs:
 
 license_file: eula.txt
 
+check_path_spaces: False
+check_path_length: False
diff --git a/examples/noconda/construct.yaml b/examples/noconda/construct.yaml
index 5c0c9014a..5a522cea2 100644
--- a/examples/noconda/construct.yaml
+++ b/examples/noconda/construct.yaml
@@ -12,3 +12,6 @@ conclusion_text: |
   You are now ready to run your Python installation.
   This is a second line and should appear as such on the installer UI.
   This would be the third one.
+
+check_path_spaces: False
+check_path_length: False
diff --git a/examples/osxpkg/construct.yaml b/examples/osxpkg/construct.yaml
index b3b82e3b8..e39618677 100644
--- a/examples/osxpkg/construct.yaml
+++ b/examples/osxpkg/construct.yaml
@@ -2,9 +2,9 @@ name: osxpkgtest
 version: 1.2.3
 
 # This config will result in a default install path:
-# ~/Library/osx-pkg-test
+# "~/Library/osx-pkg-test" (spaces not allowed because 'conda' is in 'specs')
 default_location_pkg: Library
-pkg_name: osx-pkg-test
+pkg_name: "osx-pkg-test"
 
 channels:
   - http://repo.anaconda.com/pkgs/main/
diff --git a/examples/osxpkg/test_install.sh b/examples/osxpkg/test_install.sh
index f2dbb6cb7..ce7abf0fd 100644
--- a/examples/osxpkg/test_install.sh
+++ b/examples/osxpkg/test_install.sh
@@ -1,11 +1,11 @@
-#!/bin/bash
+#!/bin/sh
 set -ex
 
-echo '## Hello from Post_install script ' > $HOME/postinstall.txt
-printenv >> $HOME/postinstall.txt
+echo '## Hello from Post_install script ' > "$HOME/postinstall.txt"
+printenv >> "$HOME/postinstall.txt"
 
 # Some tests
 # default_location_pkg
-[[ $(basename $(dirname $PREFIX)) == "Library" ]] || exit 1
+[ "$(basename "$(dirname "$PREFIX")")" = "Library" ] || exit 1
 # pkg_name
-[[ $(basename $PREFIX) == "osx-pkg-test" ]] || exit 1
+[ "$(basename "$PREFIX")" = "osx-pkg-test" ] || exit 1
diff --git a/examples/scripts/construct.yaml b/examples/scripts/construct.yaml
index 187fba4b1..97d64e197 100644
--- a/examples/scripts/construct.yaml
+++ b/examples/scripts/construct.yaml
@@ -11,3 +11,5 @@ pre_install_desc: "Adding this description makes the script selectable in the UI
 post_install: post_install.sh  # [unix]
 post_install: post_install.bat  # [win]
 post_install_desc: "Adding this description makes the script selectable in the UI"
+check_path_spaces: False
+check_path_length: False
diff --git a/examples/shortcuts/construct.yaml b/examples/shortcuts/construct.yaml
index 21ab4eaa7..238b5503f 100644
--- a/examples/shortcuts/construct.yaml
+++ b/examples/shortcuts/construct.yaml
@@ -9,3 +9,4 @@ specs:
   - python
   - conda
   - console_shortcut # [win]
+
diff --git a/examples/signing/construct.yaml b/examples/signing/construct.yaml
index f4453b415..e8bd13380 100644
--- a/examples/signing/construct.yaml
+++ b/examples/signing/construct.yaml
@@ -8,3 +8,4 @@ specs:
 # This certificate is generated an copied over on the spot during CI
 # See scripts/create_self_signed_certificate.ps1 for more info
 signing_certificate: certificate.pfx # [win]
+check_path_spaces: False
diff --git a/news/449-allow-spaces-in-prefix b/news/449-allow-spaces-in-prefix
new file mode 100644
index 000000000..5f0c40066
--- /dev/null
+++ b/news/449-allow-spaces-in-prefix
@@ -0,0 +1,22 @@
+### Enhancements:
+
+* Installers support spaces in `PREFIX` now.
+  Old behaviour (reject chosen path if it contained spaces) is still default.
+  Opt-in by setting `check_path_spaces` to `False`. (#449)
+
+### Bug fixes:
+
+* <news item>
+
+### Deprecations:
+
+* <news item>
+
+### Docs:
+
+* <news item>
+
+### Other:
+
+* <news item>
+
diff --git a/scripts/run_examples.py b/scripts/run_examples.py
index a174d2af5..88fa39ba4 100644
--- a/scripts/run_examples.py
+++ b/scripts/run_examples.py
@@ -29,15 +29,22 @@
 PY3 = sys.version_info[0] == 3
 WHITELIST = ['grin', 'jetsonconda', 'miniconda', 'newchan']
 BLACKLIST = []
+WITH_SPACES = {"extra_files", "noconda", "signing", "scripts"}
 
 
 def _execute(cmd):
     print(' '.join(cmd))
     t0 = time.time()
     p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
-    stdout, stderr = p.communicate()
+    try:
+        stdout, stderr = p.communicate(timeout=420)
+        errored = p.returncode != 0
+    except subprocess.TimeoutExpired:
+        p.kill()
+        stdout, stderr = p.communicate()
+        print('--- TEST TIMEOUT ---')
+        errored = True
     t1 = time.time()
-    errored = p.returncode != 0
     if errored:
         if stdout:
             print('--- STDOUT ---')
@@ -97,6 +104,8 @@ def run_examples(keep_artifacts=None):
         output_dir = tempfile.mkdtemp(dir=parent_output)
         # resolve path to avoid some issues with TEMPDIR on Windows
         output_dir = str(Path(output_dir).resolve())
+        example_name = Path(example_path).parent.name
+        test_with_spaces = example_name in WITH_SPACES
         cmd = COV_CMD + ['constructor', '-v', example_path, '--output-dir', output_dir]
         creation_errored = _execute(cmd)
         errored += creation_errored
@@ -105,7 +114,8 @@ def run_examples(keep_artifacts=None):
             if fpath in tested_files or ext not in ('sh', 'exe', 'pkg'):
                 continue
             tested_files.add(fpath)
-            env_dir = tempfile.mkdtemp(dir=output_dir)
+            test_suffix = "s p a c e s" if test_with_spaces else None
+            env_dir = tempfile.mkdtemp(suffix=test_suffix, dir=output_dir)
             rm_rf(env_dir)
             print('--- Testing %s' % fpath)
             fpath = os.path.join(output_dir, fpath)
@@ -169,8 +179,10 @@ def run_examples(keep_artifacts=None):
                     print('---  LOGS  ---')
                     print("Tip: Debug locally and check the full logs in the Installer UI")
                     print("     or check /var/log/install.log if run from the CLI.")
-            elif ext == "exe":
+            elif ext == "exe" and not test_with_spaces:
                 # The installer succeeded, test the uninstaller on Windows
+                # The un-installers are only tested when testing without spaces, as they hang during
+                # testing but work in UI mode.
                 uninstaller = next((p for p in os.listdir(env_dir) if p.startswith("Uninstall-")), None)
                 if uninstaller:
                     cmd = [
@@ -182,7 +194,12 @@ def run_examples(keep_artifacts=None):
                         # the tempdir cleanup later
                         f"/S _?={env_dir}"
                     ]
-                    _execute(cmd)
+                    test_errored = _execute(cmd)
+                    errored += test_errored
+                    if test_errored:
+                        which_errored.setdefault(example_path, []).append(
+                            "Wrong uninstall exit code or timeout."
+                        )
                     paths_after_uninstall = os.listdir(env_dir)
                     if len(paths_after_uninstall) > 2:
                         # The debug installer writes to install.log too, which will only
diff --git a/tests/test_header.py b/tests/test_header.py
index 9d972056b..343363a99 100644
--- a/tests/test_header.py
+++ b/tests/test_header.py
@@ -1,6 +1,11 @@
-from constructor.shar import read_header_template, preprocess
+import os
+
 import pytest
 
+from constructor.shar import read_header_template
+from constructor.utils import preprocess
+from constructor.osxpkg import OSX_DIR
+
 
 @pytest.mark.parametrize('osx', [False, True])
 @pytest.mark.parametrize('direct_execute_post_install', [False, True])
@@ -13,11 +18,12 @@
 @pytest.mark.parametrize('initialize_by_default', [False, True])
 @pytest.mark.parametrize('has_post_install', [False, True])
 @pytest.mark.parametrize('has_pre_install', [False, True])
+@pytest.mark.parametrize('check_path_spaces', [False, True])
 @pytest.mark.parametrize('arch', ['x86', 'x86_64', ' ppc64le', 's390x', 'aarch64'])
 def test_linux_template_processing(
         osx, arch, has_pre_install, has_post_install, initialize_conda,
         initialize_by_default, has_license, has_conda, keep_pkgs, batch_mode,
-        direct_execute_pre_install, direct_execute_post_install):
+        direct_execute_pre_install, direct_execute_post_install, check_path_spaces):
     template = read_header_template()
     processed = preprocess(template, {
        'has_license': has_license,
@@ -37,7 +43,31 @@ def test_linux_template_processing(
        'direct_execute_post_install': direct_execute_post_install,
        'initialize_conda': initialize_conda,
        'initialize_by_default': initialize_by_default,
+       'check_path_spaces': check_path_spaces,
+
     })
     assert '#if' not in processed
     assert '#else' not in processed
     assert '#endif' not in processed
+
+
+@pytest.mark.parametrize("arch", ["x86_64", "arm64"])
+@pytest.mark.parametrize("check_path_spaces", [False, True])
+@pytest.mark.parametrize(
+    "script", 
+    [
+        "checks_before_install.sh", 
+        "prepare_installation.sh", 
+        "run_installation.sh", 
+        "update_path.sh", 
+        "clean_cache.sh",
+        "run_user_script.sh",
+    ]
+)
+def test_osxpkg_template_processing(arch, check_path_spaces, script):
+    with open(os.path.join(OSX_DIR, script)) as f:
+        data = f.read()
+    processed = preprocess(data, {"arch": arch, "check_path_spaces": check_path_spaces})
+    assert "#if" not in processed
+    assert "#else" not in processed
+    assert "#endif" not in processed
\ No newline at end of file