CDEApp · jafin · Jun 10, 2026 · Jun 6, 2026 · Jun 6, 2026 · Jun 6, 2026
diff --git a/.nuke/build.schema.json → .fallout/build.schema.json b/.nuke/build.schema.json → .fallout/build.schema.json
@@ -44,7 +44,7 @@
         "Quiet"
       ]
     },
-    "NukeBuild": {
+    "FalloutBuild": {
       "properties": {
         "Continue": {
           "type": "boolean",
@@ -120,7 +120,7 @@
       }
     },
     {
-      "$ref": "#/definitions/NukeBuild"
+      "$ref": "#/definitions/FalloutBuild"
     }
   ]
 }
diff --git a/.nuke/parameters.json → .fallout/parameters.json b/.nuke/parameters.json → .fallout/parameters.json
diff --git a/.gitignore b/.gitignore
@@ -71,3 +71,6 @@ src/.vs/config/applicationhost.config
 **/Properties/launchSettings.json
 /.claude/settings.local.json
 /src/.claude/settings.local.json
+
+# BenchmarkDotNet writes results here when running cdeBenchmarks
+**/BenchmarkDotNet.Artifacts/
diff --git a/Readme.md b/Readme.md
@@ -30,7 +30,7 @@ This application reads and writes a configuration file `cdeWinView.cfg`.
   - size of all the columns in list views
   - values of fields in the search parameters
 
-The executable `cdeWin.exe` can be copied around by it self to be used anywhere that .Net7 is available with the behavior of the cdeWinView.cfg file as described just above.
+The executable `cdeWin.exe` can be copied around by it self to be used anywhere that .NET 10 is available with the behavior of the cdeWinView.cfg file as described just above.
 
 #### cdeWeb (unreleased)
 
@@ -109,13 +109,21 @@ cde path -find afilename
 [`-maxDateTime`](#parameter-options)
 [`-minTime`](#parameter-options)
 [`-maxTime`](#parameter-options)
+[`--desc`](#parameter-options)
+[`--follow-junctions`](#parameter-options)
 
 This is the mode of operation that creates and updates catalog files.
 
 When it creates new catalog files it will detect an old catalog file for the given scan target and copy any Hash values from the old file to the new file for matching file paths, file dates and sizes.
 
 Only Last Modified Time of file system entries is captured into .cde files.
 
+By default cde records directory junctions and symbolic links (reparse points) in the catalog but does **not** descend into them, which avoids scan cycles (for example a junction pointing back at an ancestor directory) and duplicated content. Pass `--follow-junctions` to descend into them.
+
+```
+  cde scan C:\ --follow-junctions
+```
+
 ### cde find String
 
 #### Valid Options for this mode
@@ -186,6 +194,30 @@ Consider using -minHourAge to limit Hash and Dupes work if your are cleanign up
 
 Output the full tree of file entries in the catologs in text format.
 
+### cde migrate \[Path\]
+
+#### Valid Options for this mode
+
+`No filter options supported.`
+
+This mode performs a one-way conversion of the original MessagePack `.cde` catalogs into the newer zero-copy columnar `.cdex` format. The `.cdex` format is laid out so it can be memory-mapped and searched without first deserialising the whole catalog into objects, which lowers memory use and speeds up load on large catalogs.
+
+- With a path argument, only that single `.cde` file is converted:
+
+  ```batch
+  cde migrate C-V3Win7-C__users.cde
+  ```
+
+- With no argument, every catalog discovered in the current directory and one directory below is converted (the same discovery rule used when loading catalogs):
+
+  ```batch
+  cde migrate
+  ```
+
+For each catalog a `.cdex` file is written beside the source `.cde`, keeping the same base name. The original `.cde` file is left in place and is not deleted, so the conversion is non-destructive. Re-running migrate simply overwrites the `.cdex` output.
+
+For each file converted cde prints the source and destination file names, their byte sizes and the entry count, then a summary of how many catalogs were migrated. Files that cannot be loaded are skipped and reported.
+
 ### Parameter Options
 
 |     | Parameter&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | Description                                                                                                                                                                                                                                                                                                   |
@@ -204,6 +236,8 @@ Output the full tree of file entries in the catologs in text format.
 |     | `-maxResults {Int}`                                                                                             | Maximum number of results returned by cde.                                                                                                                                                                                                                                                                    |
 |     | `-exclude {Regex}`                                                                                              | A filter to exclude only entries that match these regexes for processing.                                                                                                                                                                                                                                     |
 |     | `-include {Regex}`                                                                                              | A filter to include only entries that match these Regexes for processing.                                                                                                                                                                                                                                     |
+|     | `--desc {Text}`                                                                                                 | (scan) Description text to store in the catalog file.                                                                                                                                                                                                                                                          |
+|     | `--follow-junctions`                                                                                            | (scan) Descend into directory junctions and symbolic links (reparse points). Off by default; reparse points are recorded but not followed, avoiding scan cycles and duplicated content.                                                                                                                        |
 
 ##### Date Time Format for parameters
 

diff --git a/build.ps1 b/build.ps1
@@ -14,7 +14,7 @@ $PSScriptRoot = Split-Path $MyInvocation.MyCommand.Path -Parent
 ###########################################################################
 
 $BuildProjectFile = "$PSScriptRoot\build\_build.csproj"
-$TempDirectory = "$PSScriptRoot\\.nuke\temp"
+$TempDirectory = "$PSScriptRoot\\.fallout\temp"
 
 $DotNetGlobalFile = "$PSScriptRoot\\global.json"
 $DotNetInstallUrl = "https://dot.net/v1/dotnet-install.ps1"

diff --git a/build.sh b/build.sh
@@ -10,7 +10,7 @@ SCRIPT_DIR=$(cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd)
 ###########################################################################
 
 BUILD_PROJECT_FILE="$SCRIPT_DIR/build/_build.csproj"
-TEMP_DIRECTORY="$SCRIPT_DIR//.nuke/temp"
+TEMP_DIRECTORY="$SCRIPT_DIR//.fallout/temp"
 
 DOTNET_GLOBAL_FILE="$SCRIPT_DIR//global.json"
 DOTNET_INSTALL_URL="https://dot.net/v1/dotnet-install.sh"

diff --git a/build/Build.cs b/build/Build.cs
@@ -2,18 +2,18 @@
 using JetBrains.Annotations;
 using Microsoft.Build.Evaluation;
 using Microsoft.Build.Locator;
-using Nuke.Common;
-using Nuke.Common.CI;
-using Nuke.Common.Git;
-using Nuke.Common.IO;
-using Nuke.Common.ProjectModel;
-using Nuke.Common.Tools.DotNet;
-using Nuke.Common.Utilities.Collections;
-using static Nuke.Common.Tools.DotNet.DotNetTasks;
+using Fallout.Common;
+using Fallout.Common.CI;
+using Fallout.Common.Git;
+using Fallout.Common.IO;
+using Fallout.Common.ProjectModel;
+using Fallout.Common.Tools.DotNet;
+using Fallout.Common.Utilities.Collections;
+using static Fallout.Common.Tools.DotNet.DotNetTasks;
 // ReSharper disable AllUnderscoreLocalParameterName
 
 [ShutdownDotNetAfterServerBuild]
-class Build : NukeBuild
+class Build : FalloutBuild
 {
     public Build()
     {

diff --git a/build/Configuration.cs b/build/Configuration.cs
@@ -1,5 +1,5 @@
 using System.ComponentModel;
-using Nuke.Common.Tooling;
+using Fallout.Common.Tooling;
 
 [TypeConverter(typeof(TypeConverter<Configuration>))]
 public class Configuration : Enumeration

diff --git a/build/_build.csproj b/build/_build.csproj
@@ -5,19 +5,20 @@
     <TargetFramework>net10.0</TargetFramework>
     <RootNamespace></RootNamespace>
     <NoWarn>CS0649;CS0169</NoWarn>
-    <NukeRootDirectory>..</NukeRootDirectory>
-    <NukeScriptDirectory>..</NukeScriptDirectory>
-    <NukeTelemetryVersion>1</NukeTelemetryVersion>
+    <FalloutRootDirectory>..</FalloutRootDirectory>
+    <FalloutScriptDirectory>..</FalloutScriptDirectory>
+    <FalloutTelemetryVersion>1</FalloutTelemetryVersion>
   <EnableUnsafeBinaryFormatterSerialization>true</EnableUnsafeBinaryFormatterSerialization>
   <LangVersion>default</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="JetBrains.Annotations" Version="2025.2.4" />
     <PackageReference Include="Microsoft.Build.Locator" Version="1.11.2" />
-    <PackageReference Include="NuGet.Frameworks" Version="7.3.0" ExcludeAssets="runtime" PrivateAssets="all">
+    <PackageReference Include="NuGet.Frameworks" Version="7.6.0" ExcludeAssets="runtime" PrivateAssets="all">
       <IncludeAssets>compile; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Nuke.Common" Version="10.1.0" />
+    <PackageReference Include="Fallout.Common" Version="10.3.49" />
     <PackageDownload Include="GitVersion.Tool" Version="[5.6.7]" />
   </ItemGroup>
 

diff --git a/claude.md b/claude.md
@@ -16,14 +16,14 @@ CDE is a high-performance file system cataloging utility written in C# that crea
   - Target: .NET 10
   - Cross-platform: win-x64, linux-x64, osx-x64
   - Entry point for scan, find, hash, dupes, dump commands
-  - Dependencies: Autofac, MediatR, CommandLineParser, Spectre.Console
+  - Dependencies: Autofac, SlimMessageBus, CommandLineParser, Spectre.Console
 
 - **cdeLib** - Core library containing business logic
   - Target: .NET 10
   - Contains all catalog operations, hashing, duplicate detection
-  - Uses CQRS pattern with MediatR
-  - Serialization: MessagePack, FlatSharp
-  - Key dependencies: Autofac, MediatR, Serilog
+  - Uses CQRS pattern with SlimMessageBus
+  - Serialization: columnar `.cdex` (zero-copy, memory-mapped), plus MessagePack/FlatSharp/protobuf-net for the legacy `.cde` tree format
+  - Key dependencies: Autofac, SlimMessageBus, Serilog
 
 - **cdeWin** - Windows Forms GUI application
   - Target: .NET 10 (Windows)
@@ -52,7 +52,7 @@ CDE is a high-performance file system cataloging utility written in C# that crea
 
 ### Architecture Patterns
 
-- **CQRS (Command Query Responsibility Segregation)**: Commands and queries handled via MediatR
+- **CQRS (Command Query Responsibility Segregation)**: Commands and queries handled via SlimMessageBus (`IRequestHandler`, `IMessageBus`)
   - Commands: `CreateCacheCommand`, `HashCatalogCommand`, `FindDuplicatesCommand`, `UpdateCommand`
   - Handlers: Separate handlers for each command
   - Events: `ScanProgressEvent` for progress tracking
@@ -69,9 +69,12 @@ CDE is a high-performance file system cataloging utility written in C# that crea
 
 ### Serialization
 
-Multiple serialization formats supported:
-- **MessagePack** - Primary catalog file format (.cde files)
-- **FlatSharp** - FlatBuffers support (alternative)
+Two on-disk catalog formats:
+
+- **Columnar `.cdex`** (`Entities/Columnar/ColumnarFormat.cs`) - **Current/primary format.** A struct-of-arrays layout designed for *zero-copy reads over a memory-mapped file*: "loading" a catalog is mmap-ing it, so no managed object graph is materialised and the working set is only the file pages a query touches (reclaimable OS page cache, not GC heap). Custom binary layout with a `"CDEX"` magic header and dense, homogeneous columns (names, sizes, timestamps, hashes, tree links) — a name-only search scans just the name columns and never pages in the rest. Written directly by `scan`; read via `ColumnarCatalogReader`.
+- **Legacy `.cde` tree format** - The original materialised directory-tree format, serialized via a pluggable `SerializerProtocol` in `Catalog/CatalogRepository.cs`:
+  - **MessagePack** - default protocol for `.cde` (`MessagePackConfig.Options`, custom `Hash16Formatter`/resolver)
+  - **FlatSharp** (FlatBuffers) and **protobuf-net** - alternative protocols selectable via `SerializerProtocol`
 
 ### Hashing
 
@@ -126,15 +129,16 @@ Entry (base class)
 
 ### Build System
 
-- **Nuke Build** - Build automation
-  - `build.cmd` / `build.ps1` / `build.sh` - Build scripts
-  - `build/Build.cs` - Build definition
+- **Fallout Build** - Build automation (replaced Nuke)
+  - `build.cmd` / `build.ps1` / `build.sh` - Build scripts (bootstrap `build/_build.csproj`)
+  - `build/Build.cs` - Build definition (uses `Fallout.Common`)
+  - `.fallout/` - Fallout config, parameters, and temp/log output
   - Command: `build.cmd publish` - Creates artifacts in `./artifacts`
 
 ### Key Command Handlers
 
 Located in `cdeLib/`:
-- `Catalog/CreateCacheCommandHandler.cs` - Scans file systems, creates .cde files
+- `Catalog/CreateCacheCommandHandler.cs` - Scans file systems, writes columnar `.cdex` catalogs (reusing hashes from an existing `.cdex` when present)
 - `Hashing/HashCatalogCommandHandler.cs` - Adds MD5 hashes to catalogs
 - `Duplicates/FindDuplicateCommandHandler.cs` - Identifies duplicate files
 - `FindService.cs` - File search functionality
@@ -148,16 +152,18 @@ Located in `cdeLib/Infrastructure/`:
 - `WorkStealingTreeTraversal.cs` - Parallel directory traversal
 - `Config/` - Configuration classes
 
-## Catalog File Format (.cde)
+## Catalog File Formats (.cdex / .cde)
 
-- **Extension**: `.cde`
+- **Extensions**: `.cdex` (current columnar format) and `.cde` (legacy tree format)
 - **Naming**: Derived from drive letter, volume name, and path
-  - Example: `C-V3Win7-C__users.cde` for `C:\users\`
-  - Example: `UNC-toothless_c__users_.cde` for `\\unc\toothless\c$\users`
-- **Loading**: All .cde files in current directory or one level down are loaded
-- **Content**: Directory tree with optional MD5 hashes
+  - Example: `C-V3Win7-C__users.cdex` for `C:\users\`
+  - Example: `UNC-toothless_c__users_.cdex` for `\\unc\toothless\c$\users`
+- **Loading**: All catalog files in the current directory or one level down are loaded (`GetColumnarFileList` for `.cdex`, `GetCacheFileList` for `.cde`)
+- **Content**: Directory tree (or columns) with optional MD5 hashes
 - **Size**: Highly efficient - 500MB for 11 billion entries
-- **Format**: MessagePack binary serialization (not compressed)
+- **Format**:
+  - `.cdex` - custom columnar binary, memory-mapped for zero-copy loads (not compressed)
+  - `.cde` - MessagePack binary serialization by default (not compressed); protobuf/FlatBuffers selectable in code
 
 ## Common Operations
 
@@ -228,7 +234,7 @@ This branch focuses on performance improvements and refactoring. Recent commits
    - Use object pooling for frequently allocated objects
    - Benchmark changes that affect hot paths
 
-2. **Catalog Compatibility**: Changes to serialization affect .cde file format
+2. **Catalog Compatibility**: Changes to serialization affect the `.cdex`/`.cde` file formats
    - Hash size changes require catalog recreation
    - Document breaking changes
 
@@ -240,9 +246,18 @@ This branch focuses on performance improvements and refactoring. Recent commits
    - Unit tests in cdeLibTest
    - Specification tests in cdeLibSpec/cdeLibSpec2
 
+### Shell & Tooling
+
+This is a Windows environment with both PowerShell and Bash available. The two shells have **incompatible** here-string / quoting syntax — never mix them.
+
+- **PowerShell here-string** is `@'` ... `'@` (closing `'@` must be at column 0). Only valid in the PowerShell tool.
+- **Bash here-doc** is `<<'EOF'` ... `EOF`. Only valid in the Bash tool.
+- Passing `@'...'@` to the Bash tool does **not** create a here-string — Bash treats the `@` characters as literal text, which (for example) prepends a stray `@` to git commit messages.
+- For multi-line text (commit messages, file content) prefer the matching syntax for the tool you're calling, or write the text to a file and pass it with `-F <file>`.
+
 ### Code Patterns
 
-- **MediatR Commands**: Business operations are commands/queries
+- **SlimMessageBus Commands**: Business operations are commands/queries (`IRequestHandler<T>.OnHandle`)
 - **Dependency Injection**: Constructor injection via Autofac
 - **Logging**: Serilog with structured logging
 - **Configuration**: Microsoft.Extensions.Configuration with appsettings.json
@@ -268,8 +283,10 @@ Standard .NET test runners (tests use NUnit, xUnit)
 ## Dependencies to Note
 
 - **Autofac** - Dependency injection
-- **MediatR** - Command/query pattern
-- **MessagePack** - Primary serialization
+- **SlimMessageBus** - Command/query and pub/sub messaging (in-memory)
+- **MessagePack** - Serialization for the legacy `.cde` tree format (current `.cdex` format uses a custom columnar layout)
+- **FlatSharp** - FlatBuffers serialization (alternative `.cde` protocol)
+- **protobuf-net** - Protobuf serialization (alternative `.cde` protocol)
 - **Serilog** - Structured logging
 - **CommandLineParser** - CLI argument parsing
 - **Spectre.Console** - Rich console output

diff --git a/developer.md b/developer.md
@@ -2,13 +2,23 @@
 
 ## Building the app
 
-The build uses Nuke to perform the steps.
+The build uses Fallout to perform the steps. (It replaced Nuke.)
+
+The build definition lives in `build/Build.cs` (built on `Fallout.Common`), and the
+`build.cmd` / `build.ps1` / `build.sh` scripts bootstrap `build/_build.csproj`.
+Fallout config, parameters and temp/log output are kept under `.fallout/`.
 
 To build the app on windows run:
 
 ```shell
 build.cmd publish
 ```
 
+On Linux/macOS run:
+
+```shell
+./build.sh publish
+```
+
 Artifacts from the build will be built to `.\artifacts`