diff --git a/lib/spack/spack/package_base.py b/lib/spack/spack/package_base.py
index 8f6669d10e7..af5a4b8515b 100644
--- a/lib/spack/spack/package_base.py
+++ b/lib/spack/spack/package_base.py
@@ -767,6 +767,9 @@ def __init__(self, spec):
         self.win_rpath = fsys.WindowsSimulatedRPath(self)
         super().__init__()
 
+    def __getitem__(self, key: str) -> "PackageBase":
+        return self.spec[key].package
+
     @classmethod
     def dependency_names(cls):
         return _subkeys(cls.dependencies)
diff --git a/lib/spack/spack/test/package_class.py b/lib/spack/spack/test/package_class.py
index 255b8a67007..2730aad40c4 100644
--- a/lib/spack/spack/test/package_class.py
+++ b/lib/spack/spack/test/package_class.py
@@ -285,3 +285,16 @@ def compilers(compiler, arch_spec):
     error = capfd.readouterr()[1]
     assert "Skipping tests for package" in error
     assert "test requires missing compiler" in error
+
+
+def test_package_subscript(default_mock_concretization):
+    """Tests that we can use the subscript notation on packages, and that it returns a package"""
+    root = default_mock_concretization("mpileaks")
+    root_pkg = root.package
+
+    # Subscript of a virtual
+    assert isinstance(root_pkg["mpi"], spack.package_base.PackageBase)
+
+    # Subscript on concrete
+    for d in root.traverse():
+        assert isinstance(root_pkg[d.name], spack.package_base.PackageBase)
diff --git a/var/spack/repos/builtin/packages/cp2k/package.py b/var/spack/repos/builtin/packages/cp2k/package.py
index 6b91b0a3d6a..c80959d5990 100644
--- a/var/spack/repos/builtin/packages/cp2k/package.py
+++ b/var/spack/repos/builtin/packages/cp2k/package.py
@@ -790,7 +790,7 @@ def edit(self, pkg, spec, prefix):
                     "# include Plumed.inc as recommended by"
                     "PLUMED to include libraries and flags"
                 )
-                mkf.write("include {0}\n".format(spec["plumed"].package.plumed_inc))
+                mkf.write("include {0}\n".format(self.pkg["plumed"].plumed_inc))
 
             mkf.write("\n# COMPILER, LINKER, TOOLS\n\n")
             mkf.write(
diff --git a/var/spack/repos/builtin/packages/glvis/package.py b/var/spack/repos/builtin/packages/glvis/package.py
index 20cdc9208c4..4bd9e12a6fe 100644
--- a/var/spack/repos/builtin/packages/glvis/package.py
+++ b/var/spack/repos/builtin/packages/glvis/package.py
@@ -153,7 +153,7 @@ def common_args(self):
             "CC={0}".format(env["CC"]),
             "PREFIX={0}".format(self.spec.prefix.bin),
             "MFEM_DIR={0}".format(self.spec["mfem"].prefix),
-            "CONFIG_MK={0}".format(self.spec["mfem"].package.config_mk),
+            "CONFIG_MK={0}".format(self.pkg["mfem"].config_mk),
         ]
 
         # https://github.com/spack/spack/issues/42839
diff --git a/var/spack/repos/builtin/packages/gromacs/package.py b/var/spack/repos/builtin/packages/gromacs/package.py
index 181224f8ccd..ea9af54c6cb 100644
--- a/var/spack/repos/builtin/packages/gromacs/package.py
+++ b/var/spack/repos/builtin/packages/gromacs/package.py
@@ -585,7 +585,7 @@ def patch(self):
             )
 
         if self.spec.satisfies("+plumed"):
-            self.spec["plumed"].package.apply_patch(self)
+            self["plumed"].apply_patch(self)
 
         if self.spec.satisfies("%nvhpc"):
             # Disable obsolete workaround
diff --git a/var/spack/repos/builtin/packages/laghos/package.py b/var/spack/repos/builtin/packages/laghos/package.py
index b8194987676..1c9ca551279 100644
--- a/var/spack/repos/builtin/packages/laghos/package.py
+++ b/var/spack/repos/builtin/packages/laghos/package.py
@@ -58,8 +58,8 @@ def build_targets(self):
         spec = self.spec
 
         targets.append("MFEM_DIR=%s" % spec["mfem"].prefix)
-        targets.append("CONFIG_MK=%s" % spec["mfem"].package.config_mk)
-        targets.append("TEST_MK=%s" % spec["mfem"].package.test_mk)
+        targets.append("CONFIG_MK=%s" % self["mfem"].config_mk)
+        targets.append("TEST_MK=%s" % self["mfem"].test_mk)
         if spec.satisfies("@:2.0"):
             targets.append("CXX=%s" % spec["mpi"].mpicxx)
         if self.spec.satisfies("+ofast %gcc"):
diff --git a/var/spack/repos/builtin/packages/mfem/package.py b/var/spack/repos/builtin/packages/mfem/package.py
index 05a5239b897..d58e66eaf23 100644
--- a/var/spack/repos/builtin/packages/mfem/package.py
+++ b/var/spack/repos/builtin/packages/mfem/package.py
@@ -1309,7 +1309,7 @@ def libs(self):
     @property
     def config_mk(self):
         """Export the location of the config.mk file.
-        This property can be accessed using spec["mfem"].package.config_mk
+        This property can be accessed using pkg["mfem"].config_mk
         """
         dirs = [self.prefix, self.prefix.share.mfem]
         for d in dirs:
@@ -1321,7 +1321,7 @@ def config_mk(self):
     @property
     def test_mk(self):
         """Export the location of the test.mk file.
-        This property can be accessed using spec["mfem"].package.test_mk.
+        This property can be accessed using pkg["mfem"].test_mk.
         In version 3.3.2 and newer, the location of test.mk is also defined
         inside config.mk, variable MFEM_TEST_MK.
         """
diff --git a/var/spack/repos/builtin/packages/namd/package.py b/var/spack/repos/builtin/packages/namd/package.py
index d9de65c72c1..ab8433bc7f0 100644
--- a/var/spack/repos/builtin/packages/namd/package.py
+++ b/var/spack/repos/builtin/packages/namd/package.py
@@ -147,11 +147,9 @@ def _copy_arch_file(self, lib):
     def _append_option(self, opts, lib):
         if lib != "python":
             self._copy_arch_file(lib)
-        spec = self.spec
+        lib_pkg = self[lib]
         lib_prefix = (
-            spec[lib].package.component_prefix
-            if spec[lib].name == "intel-oneapi-mkl"
-            else spec[lib].prefix
+            lib_pkg.component_prefix if lib_pkg.name == "intel-oneapi-mkl" else lib_pkg.prefix
         )
         opts.extend(["--with-{0}".format(lib), "--{0}-prefix".format(lib), lib_prefix])
 
diff --git a/var/spack/repos/builtin/packages/nfft/package.py b/var/spack/repos/builtin/packages/nfft/package.py
index 4a599f30b4c..3bcd122d881 100644
--- a/var/spack/repos/builtin/packages/nfft/package.py
+++ b/var/spack/repos/builtin/packages/nfft/package.py
@@ -35,7 +35,7 @@ class Nfft(AutotoolsPackage):
     @property
     def fftw_selected_precisions(self):
         if not self._fftw_precisions:
-            self._fftw_precisions = self.spec["fftw"].package.selected_precisions
+            self._fftw_precisions = self["fftw"].selected_precisions
         return self._fftw_precisions
 
     def configure(self, spec, prefix):
diff --git a/var/spack/repos/builtin/packages/openvdb/package.py b/var/spack/repos/builtin/packages/openvdb/package.py
index e97930591fb..d9802f00769 100644
--- a/var/spack/repos/builtin/packages/openvdb/package.py
+++ b/var/spack/repos/builtin/packages/openvdb/package.py
@@ -84,10 +84,10 @@ def post_install(self):
                 pyso = "pyopenvdb.dylib"
             else:
                 pyso = "pyopenvdb.so"
-            pyver = "python{0}".format(spec["python"].package.version.up_to(2))
+            pyver = f"python{self['python'].version.up_to(2)}"
 
-            src = prefix.lib.join(pyver).join(pyso)
+            src = self.prefix.lib.join(pyver).join(pyso)
             if not os.path.isfile(src):
-                src = prefix.lib64.join(pyver).join(pyso)
+                src = self.prefix.lib64.join(pyver).join(pyso)
             assert os.path.isfile(src)
             os.rename(src, os.path.join(python_platlib, pyso))
diff --git a/var/spack/repos/builtin/packages/osmesa/package.py b/var/spack/repos/builtin/packages/osmesa/package.py
index 3b591a9874a..a08116dfae9 100644
--- a/var/spack/repos/builtin/packages/osmesa/package.py
+++ b/var/spack/repos/builtin/packages/osmesa/package.py
@@ -21,11 +21,11 @@ def home(self):
 
     @property
     def headers(self):
-        return self.spec["mesa"].package.libosmesa_headers
+        return self["mesa"].libosmesa_headers
 
     @property
     def libs(self):
-        return self.spec["mesa"].package.libosmesa_libs
+        return self["mesa"].libosmesa_libs
 
     @property
     def gl_headers(self):
@@ -33,4 +33,4 @@ def gl_headers(self):
 
     @property
     def gl_libs(self):
-        return self.spec["mesa"].package.libosmesa_libs
+        return self["mesa"].libosmesa_libs
diff --git a/var/spack/repos/builtin/packages/pnfft/package.py b/var/spack/repos/builtin/packages/pnfft/package.py
index 2d920b31b54..20fe8a1f5f1 100644
--- a/var/spack/repos/builtin/packages/pnfft/package.py
+++ b/var/spack/repos/builtin/packages/pnfft/package.py
@@ -31,7 +31,7 @@ class Pnfft(AutotoolsPackage):
     @property
     def fftw_selected_precisions(self):
         if not self._fftw_precisions:
-            self._fftw_precisions = self.spec["fftw"].package.selected_precisions
+            self._fftw_precisions = self["fftw"].selected_precisions
         return self._fftw_precisions
 
     def configure(self, spec, prefix):
diff --git a/var/spack/repos/builtin/packages/py-pyqt4/package.py b/var/spack/repos/builtin/packages/py-pyqt4/package.py
index 1c2f6394cd5..347ef9d2ac1 100644
--- a/var/spack/repos/builtin/packages/py-pyqt4/package.py
+++ b/var/spack/repos/builtin/packages/py-pyqt4/package.py
@@ -43,7 +43,7 @@ def configure_args(self):
             "--sip",
             self.spec["py-sip"].prefix.bin.sip,
             "--sip-incdir",
-            join_path(self.spec["py-sip"].prefix, self.spec["python"].package.include),
+            join_path(self.spec["py-sip"].prefix, self["python"].include),
             "--bindir",
             self.prefix.bin,
             "--destdir",
diff --git a/var/spack/repos/builtin/packages/py-sip/package.py b/var/spack/repos/builtin/packages/py-sip/package.py
index f9913dfd4d1..428fc74973f 100644
--- a/var/spack/repos/builtin/packages/py-sip/package.py
+++ b/var/spack/repos/builtin/packages/py-sip/package.py
@@ -71,7 +71,7 @@ def install(self, spec, prefix):
             "--sip-module={0}".format(spec.variants["module"].value),
             "--bindir={0}".format(prefix.bin),
             "--destdir={0}".format(python_platlib),
-            "--incdir={0}".format(join_path(prefix, spec["python"].package.include)),
+            "--incdir={0}".format(join_path(prefix, self["python"].include)),
             "--sipdir={0}".format(prefix.share.sip),
             "--stubsdir={0}".format(python_platlib),
         ]
diff --git a/var/spack/repos/builtin/packages/qgis/package.py b/var/spack/repos/builtin/packages/qgis/package.py
index 613b4906e9c..cbc87e63618 100644
--- a/var/spack/repos/builtin/packages/qgis/package.py
+++ b/var/spack/repos/builtin/packages/qgis/package.py
@@ -217,9 +217,7 @@ def fix_qsci_sip(self):
         elif "^py-pyqt6" in self.spec:
             pyqtx = "PyQt6"
 
-        sip_inc_dir = join_path(
-            self.spec["qscintilla"].package.module.python_platlib, pyqtx, "bindings"
-        )
+        sip_inc_dir = join_path(self["qscintilla"].module.python_platlib, pyqtx, "bindings")
         with open(join_path("python", "gui", "pyproject.toml.in"), "a") as tomlfile:
             tomlfile.write(f'\n[tool.sip.project]\nsip-include-dirs = ["{sip_inc_dir}"]\n')
 
diff --git a/var/spack/repos/builtin/packages/qscintilla/package.py b/var/spack/repos/builtin/packages/qscintilla/package.py
index 234e740e03a..f70f84817d2 100644
--- a/var/spack/repos/builtin/packages/qscintilla/package.py
+++ b/var/spack/repos/builtin/packages/qscintilla/package.py
@@ -101,9 +101,7 @@ def make_qsci_python(self):
 
         with working_dir(join_path(self.stage.source_path, "Python")):
             copy(ftoml, "pyproject.toml")
-            sip_inc_dir = join_path(
-                self.spec[py_pyqtx].package.module.python_platlib, pyqtx, "bindings"
-            )
+            sip_inc_dir = join_path(self[py_pyqtx].module.python_platlib, pyqtx, "bindings")
 
             with open("pyproject.toml", "a") as tomlfile:
                 # https://pyqt-builder.readthedocs.io/en/latest/pyproject_toml.html
diff --git a/var/spack/repos/builtin/packages/remhos/package.py b/var/spack/repos/builtin/packages/remhos/package.py
index 50481808f66..b365f9a5865 100644
--- a/var/spack/repos/builtin/packages/remhos/package.py
+++ b/var/spack/repos/builtin/packages/remhos/package.py
@@ -38,14 +38,11 @@ class Remhos(MakefilePackage):
 
     @property
     def build_targets(self):
-        targets = []
-        spec = self.spec
-
-        targets.append("MFEM_DIR=%s" % spec["mfem"].prefix)
-        targets.append("CONFIG_MK=%s" % spec["mfem"].package.config_mk)
-        targets.append("TEST_MK=%s" % spec["mfem"].package.test_mk)
-
-        return targets
+        return [
+            f"MFEM_DIR={self['mfem'].prefix}",
+            f"CONFIG_MK={self['mfem'].config_mk}",
+            f"TEST_MK={self['mfem'].test_mk}",
+        ]
 
     # See lib/spack/spack/build_systems/makefile.py
     def check(self):
diff --git a/var/spack/repos/builtin/packages/tau/package.py b/var/spack/repos/builtin/packages/tau/package.py
index 19067a3e7d9..6c3382ce001 100644
--- a/var/spack/repos/builtin/packages/tau/package.py
+++ b/var/spack/repos/builtin/packages/tau/package.py
@@ -323,8 +323,8 @@ def install(self, spec, prefix):
                 env["F77"] = spec["mpi"].mpif77
                 env["FC"] = spec["mpi"].mpifc
             if spec["mpi"].name == "intel-oneapi-mpi":
-                options.append("-mpiinc=%s/include" % spec["mpi"].package.component_prefix)
-                options.append("-mpilib=%s/lib" % spec["mpi"].package.component_prefix)
+                options.append("-mpiinc=%s/include" % self["mpi"].component_prefix)
+                options.append("-mpilib=%s/lib" % self["mpi"].component_prefix)
             else:
                 options.append("-mpiinc=%s" % spec["mpi"].prefix.include)
                 options.append("-mpilib=%s" % spec["mpi"].prefix.lib)