diff --git a/.pylintrc-local.yml b/.pylintrc-local.yml
index 3d83b68d..dc1459d9 100644
--- a/.pylintrc-local.yml
+++ b/.pylintrc-local.yml
@@ -1,6 +1,2 @@
 - arg: extension-pkg-whitelist
   val: pyfmmlib
-
-# Needed for boxtree.tools
-- arg: init-hook
-  val: import sys; sys.setrecursionlimit(2000)
diff --git a/boxtree/__init__.py b/boxtree/__init__.py
index 85080390..8b4b34ad 100644
--- a/boxtree/__init__.py
+++ b/boxtree/__init__.py
@@ -111,15 +111,15 @@
 two arrays, one whose name ends in ``_starts``, and another whose
 name ends in ``_lists``. For example,
 suppose we would like to find the colleagues of box #17 using
-:attr:`boxtree.traversal.FMMTraversalInfo.colleagues_starts`
+:attr:`boxtree.traversal.FMMTraversalInfo.same_level_non_well_sep_boxes_starts`
 and
-:attr:`boxtree.traversal.FMMTraversalInfo.colleagues_lists`.
+:attr:`boxtree.traversal.FMMTraversalInfo.same_level_non_well_sep_boxes_lists`.
 
 The following snippet of code achieves this::
 
     ibox = 17
-    start, end = colleagues_starts[ibox:ibox+2]
-    ibox_colleagues = colleagues_lists[start:end]
+    start, end = same_level_non_well_sep_boxes_starts[ibox:ibox+2]
+    ibox_colleagues = same_level_non_well_sep_boxes_lists[start:end]
 
 This indexing scheme has the following properties:
 
diff --git a/boxtree/tree.py b/boxtree/tree.py
index 519140d8..00e3e4b7 100644
--- a/boxtree/tree.py
+++ b/boxtree/tree.py
@@ -52,10 +52,6 @@
 ^^^^^
 
 .. autoclass:: ParticleListFilter
-
-.. autofunction:: filter_target_lists_in_user_order
-
-.. autofunction:: filter_target_lists_in_tree_order
 """
 
 __copyright__ = "Copyright (C) 2013 Andreas Kloeckner"
diff --git a/doc/Makefile b/doc/Makefile
index c45814ac..d0ac5f2f 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -1,130 +1,20 @@
-# Makefile for Sphinx documentation
+# Minimal makefile for Sphinx documentation
 #
 
-# You can set these variables from the command line.
-SPHINXOPTS    =
-SPHINXBUILD   = python $(shell which sphinx-build)
-PAPER         =
+# You can set these variables from the command line, and also
+# from the environment for the first two.
+SPHINXOPTS    ?=
+SPHINXBUILD   ?= python $(shell which sphinx-build)
+SOURCEDIR     = .
 BUILDDIR      = _build
 
-# Internal variables.
-PAPEROPT_a4     = -D latex_paper_size=a4
-PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
-
-.PHONY: help clean html dirhtml singlehtml pickle json htmlhelp qthelp devhelp epub latex latexpdf text man changes linkcheck doctest
-
+# Put it first so that "make" without argument is like "make help".
 help:
-	@echo "Please use \`make <target>' where <target> is one of"
-	@echo "  html       to make standalone HTML files"
-	@echo "  dirhtml    to make HTML files named index.html in directories"
-	@echo "  singlehtml to make a single large HTML file"
-	@echo "  pickle     to make pickle files"
-	@echo "  json       to make JSON files"
-	@echo "  htmlhelp   to make HTML files and a HTML help project"
-	@echo "  qthelp     to make HTML files and a qthelp project"
-	@echo "  devhelp    to make HTML files and a Devhelp project"
-	@echo "  epub       to make an epub"
-	@echo "  latex      to make LaTeX files, you can set PAPER=a4 or PAPER=letter"
-	@echo "  latexpdf   to make LaTeX files and run them through pdflatex"
-	@echo "  text       to make text files"
-	@echo "  man        to make manual pages"
-	@echo "  changes    to make an overview of all changed/added/deprecated items"
-	@echo "  linkcheck  to check all external links for integrity"
-	@echo "  doctest    to run all doctests embedded in the documentation (if enabled)"
-
-clean:
-	-rm -rf $(BUILDDIR)/*
-
-html:
-	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
-	@echo
-	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
-
-dirhtml:
-	$(SPHINXBUILD) -b dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
-	@echo
-	@echo "Build finished. The HTML pages are in $(BUILDDIR)/dirhtml."
-
-singlehtml:
-	$(SPHINXBUILD) -b singlehtml $(ALLSPHINXOPTS) $(BUILDDIR)/singlehtml
-	@echo
-	@echo "Build finished. The HTML page is in $(BUILDDIR)/singlehtml."
-
-pickle:
-	$(SPHINXBUILD) -b pickle $(ALLSPHINXOPTS) $(BUILDDIR)/pickle
-	@echo
-	@echo "Build finished; now you can process the pickle files."
-
-json:
-	$(SPHINXBUILD) -b json $(ALLSPHINXOPTS) $(BUILDDIR)/json
-	@echo
-	@echo "Build finished; now you can process the JSON files."
-
-htmlhelp:
-	$(SPHINXBUILD) -b htmlhelp $(ALLSPHINXOPTS) $(BUILDDIR)/htmlhelp
-	@echo
-	@echo "Build finished; now you can run HTML Help Workshop with the" \
-	      ".hhp project file in $(BUILDDIR)/htmlhelp."
-
-qthelp:
-	$(SPHINXBUILD) -b qthelp $(ALLSPHINXOPTS) $(BUILDDIR)/qthelp
-	@echo
-	@echo "Build finished; now you can run "qcollectiongenerator" with the" \
-	      ".qhcp project file in $(BUILDDIR)/qthelp, like this:"
-	@echo "# qcollectiongenerator $(BUILDDIR)/qthelp/boxtree.qhcp"
-	@echo "To view the help file:"
-	@echo "# assistant -collectionFile $(BUILDDIR)/qthelp/boxtree.qhc"
-
-devhelp:
-	$(SPHINXBUILD) -b devhelp $(ALLSPHINXOPTS) $(BUILDDIR)/devhelp
-	@echo
-	@echo "Build finished."
-	@echo "To view the help file:"
-	@echo "# mkdir -p $$HOME/.local/share/devhelp/boxtree"
-	@echo "# ln -s $(BUILDDIR)/devhelp $$HOME/.local/share/devhelp/boxtree"
-	@echo "# devhelp"
-
-epub:
-	$(SPHINXBUILD) -b epub $(ALLSPHINXOPTS) $(BUILDDIR)/epub
-	@echo
-	@echo "Build finished. The epub file is in $(BUILDDIR)/epub."
-
-latex:
-	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
-	@echo
-	@echo "Build finished; the LaTeX files are in $(BUILDDIR)/latex."
-	@echo "Run \`make' in that directory to run these through (pdf)latex" \
-	      "(use \`make latexpdf' here to do that automatically)."
-
-latexpdf:
-	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
-	@echo "Running LaTeX files through pdflatex..."
-	make -C $(BUILDDIR)/latex all-pdf
-	@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
-
-text:
-	$(SPHINXBUILD) -b text $(ALLSPHINXOPTS) $(BUILDDIR)/text
-	@echo
-	@echo "Build finished. The text files are in $(BUILDDIR)/text."
-
-man:
-	$(SPHINXBUILD) -b man $(ALLSPHINXOPTS) $(BUILDDIR)/man
-	@echo
-	@echo "Build finished. The manual pages are in $(BUILDDIR)/man."
-
-changes:
-	$(SPHINXBUILD) -b changes $(ALLSPHINXOPTS) $(BUILDDIR)/changes
-	@echo
-	@echo "The overview file is in $(BUILDDIR)/changes."
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
 
-linkcheck:
-	$(SPHINXBUILD) -b linkcheck $(ALLSPHINXOPTS) $(BUILDDIR)/linkcheck
-	@echo
-	@echo "Link check complete; look for any errors in the above output " \
-	      "or in $(BUILDDIR)/linkcheck/output.txt."
+.PHONY: help Makefile
 
-doctest:
-	$(SPHINXBUILD) -b doctest $(ALLSPHINXOPTS) $(BUILDDIR)/doctest
-	@echo "Testing of doctests in the sources finished, look at the " \
-	      "results in $(BUILDDIR)/doctest/output.txt."
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
diff --git a/doc/conf.py b/doc/conf.py
index 07572b6c..8a9553ac 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -18,5 +18,6 @@
         "https://docs.python.org/3/": None,
         "https://numpy.org/doc/stable/": None,
         "https://documen.tician.de/pyopencl/": None,
+        "https://documen.tician.de/arraycontext/": None,
         "https://documen.tician.de/pytential/": None,
         }
diff --git a/doc/tools.rst b/doc/tools.rst
index 6db9bc70..0b5225ee 100644
--- a/doc/tools.rst
+++ b/doc/tools.rst
@@ -4,3 +4,5 @@ Utility Functionality
 .. automodule:: boxtree.timing
 
 .. automodule:: boxtree.constant_one
+
+.. automodule:: boxtree.array_context