diff --git a/accumulators/.settings/org.eclipse.core.resources.prefs b/accumulators/.settings/org.eclipse.core.resources.prefs
new file mode 100644
index 0000000..99f26c0
--- /dev/null
+++ b/accumulators/.settings/org.eclipse.core.resources.prefs
@@ -0,0 +1,2 @@
+eclipse.preferences.version=1
+encoding/<project>=UTF-8
diff --git a/accumulators/.settings/org.eclipse.jdt.core.prefs b/accumulators/.settings/org.eclipse.jdt.core.prefs
new file mode 100644
index 0000000..9a7984b
--- /dev/null
+++ b/accumulators/.settings/org.eclipse.jdt.core.prefs
@@ -0,0 +1,11 @@
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=21
+org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
+org.eclipse.jdt.core.compiler.compliance=21
+org.eclipse.jdt.core.compiler.debug.lineNumber=generate
+org.eclipse.jdt.core.compiler.debug.localVariable=generate
+org.eclipse.jdt.core.compiler.debug.sourceFile=generate
+org.eclipse.jdt.core.compiler.problem.enablePreviewFeatures=disabled
+org.eclipse.jdt.core.compiler.problem.reportPreviewFeatures=warning
+org.eclipse.jdt.core.compiler.release=enabled
+org.eclipse.jdt.core.compiler.source=21
diff --git a/trees/.settings/org.eclipse.core.resources.prefs b/trees/.settings/org.eclipse.core.resources.prefs
new file mode 100644
index 0000000..99f26c0
--- /dev/null
+++ b/trees/.settings/org.eclipse.core.resources.prefs
@@ -0,0 +1,2 @@
+eclipse.preferences.version=1
+encoding/<project>=UTF-8
diff --git a/trees/.settings/org.eclipse.jdt.core.prefs b/trees/.settings/org.eclipse.jdt.core.prefs
new file mode 100644
index 0000000..9a7984b
--- /dev/null
+++ b/trees/.settings/org.eclipse.jdt.core.prefs
@@ -0,0 +1,11 @@
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=21
+org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
+org.eclipse.jdt.core.compiler.compliance=21
+org.eclipse.jdt.core.compiler.debug.lineNumber=generate
+org.eclipse.jdt.core.compiler.debug.localVariable=generate
+org.eclipse.jdt.core.compiler.debug.sourceFile=generate
+org.eclipse.jdt.core.compiler.problem.enablePreviewFeatures=disabled
+org.eclipse.jdt.core.compiler.problem.reportPreviewFeatures=warning
+org.eclipse.jdt.core.compiler.release=enabled
+org.eclipse.jdt.core.compiler.source=21