diff --git a/lib/src/installer/completion_configuration.dart b/lib/src/installer/completion_configuration.dart
new file mode 100644
index 0000000..7a10957
--- /dev/null
+++ b/lib/src/installer/completion_configuration.dart
@@ -0,0 +1,139 @@
+import 'dart:collection';
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:cli_completion/installer.dart';
+import 'package:cli_completion/parser.dart';
+import 'package:meta/meta.dart';
+
+/// A map of [SystemShell]s to a list of uninstalled commands.
+///
+/// The map and its content are unmodifiable. This is to ensure that
+/// [CompletionConfiguration]s is fully immutable.
+typedef Uninstalls
+    = UnmodifiableMapView<SystemShell, UnmodifiableSetView<String>>;
+
+/// {@template completion_configuration}
+/// A configuration that stores information on how to handle command
+/// completions.
+/// {@endtemplate}
+@immutable
+class CompletionConfiguration {
+  /// {@macro completion_configuration}
+  const CompletionConfiguration._({
+    required this.uninstalls,
+  });
+
+  /// Creates an empty [CompletionConfiguration].
+  @visibleForTesting
+  CompletionConfiguration.empty() : uninstalls = UnmodifiableMapView({});
+
+  /// Creates a [CompletionConfiguration] from the given [file] content.
+  ///
+  /// If the file does not exist or is empty, a [CompletionConfiguration.empty]
+  /// is created.
+  ///
+  /// If the file is not empty, a [CompletionConfiguration] is created from the
+  /// file's content. This content is assumed to be a JSON string. The parsing
+  /// is handled gracefully, so if the JSON is partially or fully invalid, it
+  /// handles issues without throwing an [Exception].
+  factory CompletionConfiguration.fromFile(File file) {
+    if (!file.existsSync()) {
+      return CompletionConfiguration.empty();
+    }
+
+    final json = file.readAsStringSync();
+    return CompletionConfiguration._fromJson(json);
+  }
+
+  /// Creates a [CompletionConfiguration] from the given JSON string.
+  factory CompletionConfiguration._fromJson(String json) {
+    late final Map<String, dynamic> decodedJson;
+    try {
+      decodedJson = jsonDecode(json) as Map<String, dynamic>;
+    } on FormatException {
+      decodedJson = {};
+    }
+
+    return CompletionConfiguration._(
+      uninstalls: _jsonDecodeUninstalls(decodedJson),
+    );
+  }
+
+  /// The JSON key for the [uninstalls] field.
+  static const String _uninstallsJsonKey = 'uninstalls';
+
+  /// Stores those commands that have been manually uninstalled by the user.
+  ///
+  /// Uninstalls are specific to a given [SystemShell].
+  final Uninstalls uninstalls;
+
+  /// Stores the [CompletionConfiguration] in the given [file].
+  void writeTo(File file) {
+    if (!file.existsSync()) {
+      file.createSync(recursive: true);
+    }
+    file.writeAsStringSync(_toJson());
+  }
+
+  /// Returns a copy of this [CompletionConfiguration] with the given fields
+  /// replaced.
+  CompletionConfiguration copyWith({
+    Uninstalls? uninstalls,
+  }) {
+    return CompletionConfiguration._(
+      uninstalls: uninstalls ?? this.uninstalls,
+    );
+  }
+
+  /// Returns a JSON representation of this [CompletionConfiguration].
+  String _toJson() {
+    return jsonEncode({
+      _uninstallsJsonKey: _jsonEncodeUninstalls(uninstalls),
+    });
+  }
+}
+
+/// Decodes [Uninstalls] from the given [json].
+///
+/// If the [json] is not partially or fully valid, it handles issues gracefully
+/// without throwing an [Exception].
+Uninstalls _jsonDecodeUninstalls(Map<String, dynamic> json) {
+  if (!json.containsKey(CompletionConfiguration._uninstallsJsonKey)) {
+    return UnmodifiableMapView({});
+  }
+  final jsonUninstalls = json[CompletionConfiguration._uninstallsJsonKey];
+  if (jsonUninstalls is! String) {
+    return UnmodifiableMapView({});
+  }
+  late final Map<String, dynamic> decodedUninstalls;
+  try {
+    decodedUninstalls = jsonDecode(jsonUninstalls) as Map<String, dynamic>;
+  } on FormatException {
+    return UnmodifiableMapView({});
+  }
+
+  final newUninstalls = <SystemShell, UnmodifiableSetView<String>>{};
+  for (final entry in decodedUninstalls.entries) {
+    final systemShell = SystemShell.tryParse(entry.key);
+    if (systemShell == null) continue;
+    final uninstallSet = <String>{};
+    if (entry.value is List) {
+      for (final uninstall in entry.value as List) {
+        if (uninstall is String) {
+          uninstallSet.add(uninstall);
+        }
+      }
+    }
+    newUninstalls[systemShell] = UnmodifiableSetView(uninstallSet);
+  }
+  return UnmodifiableMapView(newUninstalls);
+}
+
+/// Returns a JSON representation of the given [Uninstalls].
+String _jsonEncodeUninstalls(Uninstalls uninstalls) {
+  return jsonEncode({
+    for (final entry in uninstalls.entries)
+      entry.key.toString(): entry.value.toList(),
+  });
+}
diff --git a/lib/src/installer/installer.dart b/lib/src/installer/installer.dart
index 03776bd..f341398 100644
--- a/lib/src/installer/installer.dart
+++ b/lib/src/installer/installer.dart
@@ -1,3 +1,4 @@
+export 'completion_configuration.dart';
 export 'completion_installation.dart';
 export 'exceptions.dart';
 export 'script_configuration_entry.dart';
diff --git a/lib/src/system_shell.dart b/lib/src/system_shell.dart
index 1ce1568..ec744c7 100644
--- a/lib/src/system_shell.dart
+++ b/lib/src/system_shell.dart
@@ -54,7 +54,16 @@ enum SystemShell {
       // On windows basename can be bash.exe
       return SystemShell.bash;
     }
+    return null;
+  }
 
+  /// Tries to parse a [SystemShell] from a [String].
+  ///
+  /// Returns `null` if the [value] does not match any of the shells.
+  static SystemShell? tryParse(String value) {
+    for (final shell in SystemShell.values) {
+      if (value == shell.name || value == shell.toString()) return shell;
+    }
     return null;
   }
 }
diff --git a/test/src/installer/completion_configuration_test.dart b/test/src/installer/completion_configuration_test.dart
new file mode 100644
index 0000000..ae158e8
--- /dev/null
+++ b/test/src/installer/completion_configuration_test.dart
@@ -0,0 +1,196 @@
+// ignore_for_file: prefer_const_constructors
+
+import 'dart:collection';
+import 'dart:io';
+
+import 'package:cli_completion/installer.dart';
+import 'package:path/path.dart' as path;
+import 'package:test/test.dart';
+
+void main() {
+  group('$CompletionConfiguration', () {
+    final testUninstalls = UnmodifiableMapView({
+      SystemShell.bash: UnmodifiableSetView({'very_bad'}),
+    });
+
+    group('fromFile', () {
+      test(
+        'returns empty cache when file does not exist',
+        () {
+          final tempDirectory = Directory.systemTemp.createTempSync();
+          addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+          final file = File(path.join(tempDirectory.path, 'config.json'));
+          expect(
+            file.existsSync(),
+            isFalse,
+            reason: 'File should not exist',
+          );
+
+          final cache = CompletionConfiguration.fromFile(file);
+          expect(
+            cache.uninstalls,
+            isEmpty,
+            reason: 'Uninstalls should be initially empty',
+          );
+        },
+      );
+
+      test('returns empty cache when file is empty', () {
+        final tempDirectory = Directory.systemTemp.createTempSync();
+        addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+        final file = File(path.join(tempDirectory.path, 'config.json'))
+          ..writeAsStringSync('');
+
+        final cache = CompletionConfiguration.fromFile(file);
+        expect(
+          cache.uninstalls,
+          isEmpty,
+          reason: 'Uninstalls should be initially empty',
+        );
+      });
+
+      test("returns a $CompletionConfiguration with the file's defined members",
+          () {
+        final tempDirectory = Directory.systemTemp.createTempSync();
+        addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+        final file = File(path.join(tempDirectory.path, 'config.json'));
+        final cache = CompletionConfiguration.empty().copyWith(
+          uninstalls: testUninstalls,
+        )..writeTo(file);
+
+        final newCache = CompletionConfiguration.fromFile(file);
+        expect(
+          newCache.uninstalls,
+          cache.uninstalls,
+          reason: 'Uninstalls should match those defined in the file',
+        );
+      });
+
+      test(
+        '''returns a $CompletionConfiguration with empty uninstalls if the file's JSON "uninstalls" key has a string value''',
+        () {
+          final tempDirectory = Directory.systemTemp.createTempSync();
+          addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+          const json = '{"uninstalls": "very_bad"}';
+          final file = File(path.join(tempDirectory.path, 'config.json'))
+            ..writeAsStringSync(json);
+
+          final cache = CompletionConfiguration.fromFile(file);
+          expect(
+            cache.uninstalls,
+            isEmpty,
+            reason:
+                '''Uninstalls should be empty when the value is of an invalid type''',
+          );
+        },
+      );
+
+      test(
+        '''returns a $CompletionConfiguration with empty uninstalls if file's JSON "uninstalls" key has a numeric value''',
+        () {
+          final tempDirectory = Directory.systemTemp.createTempSync();
+          addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+          const json = '{"uninstalls": 1}';
+          final file = File(path.join(tempDirectory.path, 'config.json'))
+            ..writeAsStringSync(json);
+
+          final cache = CompletionConfiguration.fromFile(file);
+          expect(
+            cache.uninstalls,
+            isEmpty,
+            reason:
+                '''Uninstalls should be empty when the value is of an invalid type''',
+          );
+        },
+      );
+    });
+
+    group('writeTo', () {
+      test('creates a file when it does not exist', () {
+        final tempDirectory = Directory.systemTemp.createTempSync();
+        addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+        final file = File(path.join(tempDirectory.path, 'config.json'));
+        expect(
+          file.existsSync(),
+          isFalse,
+          reason: 'File should not exist',
+        );
+
+        CompletionConfiguration.empty().writeTo(file);
+
+        expect(
+          file.existsSync(),
+          isTrue,
+          reason: 'File should exist after cache creation',
+        );
+      });
+
+      test('returns normally when file already exists', () {
+        final tempDirectory = Directory.systemTemp.createTempSync();
+        addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+        final file = File(path.join(tempDirectory.path, 'config.json'))
+          ..createSync();
+        expect(
+          file.existsSync(),
+          isTrue,
+          reason: 'File should exist',
+        );
+
+        expect(
+          () => CompletionConfiguration.empty().writeTo(file),
+          returnsNormally,
+          reason: 'Should not throw when file exists',
+        );
+      });
+
+      test('content can be read succesfully after written', () {
+        final tempDirectory = Directory.systemTemp.createTempSync();
+        addTearDown(() => tempDirectory.deleteSync(recursive: true));
+
+        final file = File(path.join(tempDirectory.path, 'config.json'));
+        final cache = CompletionConfiguration.empty().copyWith(
+          uninstalls: testUninstalls,
+        )..writeTo(file);
+
+        final newCache = CompletionConfiguration.fromFile(file);
+        expect(
+          newCache.uninstalls,
+          cache.uninstalls,
+          reason: 'Uninstalls should match those defined in the file',
+        );
+      });
+    });
+
+    group('copyWith', () {
+      test('members remain unchanged when nothing is specified', () {
+        final cache = CompletionConfiguration.empty();
+        final newCache = cache.copyWith();
+
+        expect(
+          newCache.uninstalls,
+          cache.uninstalls,
+          reason: 'Uninstalls should remain unchanged',
+        );
+      });
+
+      test('modifies uninstalls when specified', () {
+        final cache = CompletionConfiguration.empty();
+        final uninstalls = testUninstalls;
+        final newCache = cache.copyWith(uninstalls: uninstalls);
+
+        expect(
+          newCache.uninstalls,
+          equals(uninstalls),
+          reason: 'Uninstalls should be modified',
+        );
+      });
+    });
+  });
+}
diff --git a/test/src/system_shell_test.dart b/test/src/system_shell_test.dart
index fa819af..5c6a97f 100644
--- a/test/src/system_shell_test.dart
+++ b/test/src/system_shell_test.dart
@@ -103,5 +103,43 @@ void main() {
         });
       });
     });
+
+    group('tryParse', () {
+      group('returns bash', () {
+        test('when given "bash"', () {
+          expect(
+            SystemShell.tryParse('bash'),
+            equals(SystemShell.bash),
+          );
+        });
+
+        test('when given "SystemShell.bash"', () {
+          expect(
+            SystemShell.tryParse('SystemShell.bash'),
+            equals(SystemShell.bash),
+          );
+        });
+      });
+
+      group('returns zsh', () {
+        test('when given "zsh"', () {
+          expect(
+            SystemShell.tryParse('zsh'),
+            equals(SystemShell.zsh),
+          );
+        });
+
+        test('when given "SystemShell.zsh"', () {
+          expect(
+            SystemShell.tryParse('SystemShell.zsh'),
+            equals(SystemShell.zsh),
+          );
+        });
+      });
+
+      test('returns null for unknown shell', () {
+        expect(SystemShell.tryParse('unknown'), equals(null));
+      });
+    });
   });
 }