Milestone 0 completed.

Docs/Architecture.md

@@ -11,6 +11,7 @@ Sapling is organized as a Swift Package with an executable app target and focuse
 - `SaplingEditor`: Hybrid Markdown editor state and SwiftUI editing surface.
 - `SaplingRenderer`: Markdown parsing/rendering primitives for headings, emphasis, code blocks, task lists, and images.
 - `SaplingStorage`: Configuration and workspace metadata persistence contracts.
+- `SaplingLogging`: Thin logging facade over `OSLog`.
 - `SaplingUI`: Shared SwiftUI sidebar, inspector, and empty-state components.
 
 ## Architectural Decisions
@@ -23,6 +24,12 @@ The editor follows an MVVM shape. `HybridMarkdownEditorViewModel` owns document
 
 Storage is abstracted behind small protocols. The current in-memory stores make the application buildable and testable; `JSONWorkspaceMetadataStore` establishes the first production path for workspace metadata without forcing a database decision.
 
+Dependency injection starts in `SaplingApp` through `AppDependencies`. The composition root owns concrete providers and passes protocols into application state. This keeps feature modules testable and prevents UI code from constructing infrastructure ad hoc.
+
+Settings are represented by `SaplingConfiguration`, persisted by `ConfigurationStore`, and exposed through the SwiftUI `Settings` scene. Logging flows through `SaplingLogger` so feature code uses stable categories without depending directly on logger construction details.
+
+The development workflow is captured in `Makefile` and `Scripts/`. `make validate` runs formatting, linting, build, and tests; this is the Milestone 0 gate before updating roadmap status.
+
 ## TODO
 
 - TODO: Replace sample data composition with real workspace opening and file loading.

Makefile

@@ -0,0 +1,15 @@
+.PHONY: build test format lint validate
+
+build:
+	swift build
+
+test:
+	swift test
+
+format:
+	sh Scripts/format.sh
+
+lint:
+	sh Scripts/lint.sh
+
+validate: format lint build test

Package.swift

@@ -16,6 +16,7 @@ let package = Package(
         .library(name: "SaplingEditor", targets: ["SaplingEditor"]),
         .library(name: "SaplingRenderer", targets: ["SaplingRenderer"]),
         .library(name: "SaplingStorage", targets: ["SaplingStorage"]),
+        .library(name: "SaplingLogging", targets: ["SaplingLogging"]),
         .library(name: "SaplingUI", targets: ["SaplingUI"])
     ],
     targets: [
@@ -28,6 +29,7 @@ let package = Package(
                 "SaplingEditor",
                 "SaplingRenderer",
                 "SaplingStorage",
+                "SaplingLogging",
                 "SaplingUI"
             ]
         ),
@@ -52,9 +54,10 @@ let package = Package(
             name: "SaplingStorage",
             dependencies: ["SaplingCore"]
         ),
+        .target(name: "SaplingLogging"),
         .target(
             name: "SaplingUI",
-            dependencies: ["SaplingCore", "SaplingWorkspace", "SaplingGit", "SaplingEditor"]
+            dependencies: ["SaplingCore", "SaplingWorkspace", "SaplingGit", "SaplingEditor", "SaplingStorage"]
         ),
         .testTarget(
             name: "SaplingCoreTests",

README

@@ -189,6 +189,14 @@ Test:
 swift test
 ```
 
+Validate the Milestone 0 development workflow:
+
+```sh
+make validate
+```
+
+The validation target runs formatting, linting, build, and tests. If `swift-format` is installed, `make format` formats Swift sources in place; otherwise it falls back to the repository lint checks.
+
 The initial app shell launches with a sample workspace tree, a hybrid Markdown editor, a Git/project inspector, and a mock Git provider. The architecture is intentionally protocol-first so the macOS implementation can use system Git while future iOS support can use an embedded Git implementation behind the same interfaces.
 
 See [Docs/Architecture.md](Docs/Architecture.md) for module responsibilities, architectural decisions, and TODO markers.

Scripts/format.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+set -eu
+
+ROOT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
+cd "$ROOT_DIR"
+
+if command -v swift-format >/dev/null 2>&1; then
+  swift-format --in-place --recursive Package.swift Sources Tests
+else
+  echo "swift-format not found; checking formatting invariants only."
+  sh Scripts/lint.sh
+fi

Scripts/lint.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+set -eu
+
+ROOT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
+cd "$ROOT_DIR"
+
+FILES=$(find Package.swift Sources Tests -type f -name '*.swift' | sort)
+
+if [ -z "$FILES" ]; then
+  echo "No Swift files found."
+  exit 0
+fi
+
+if grep -n '[[:blank:]]$' $FILES; then
+  echo "Trailing whitespace found."
+  exit 1
+fi
+
+if grep -n "$(printf '\t')" $FILES; then
+  echo "Tabs found; use spaces for Swift source indentation."
+  exit 1
+fi
+
+echo "Lint passed."

Sources/SaplingApp/AppDependencies.swift

@@ -0,0 +1,60 @@
+import Foundation
+import SaplingGit
+import SaplingLogging
+import SaplingStorage
+import SaplingWorkspace
+
+struct AppDependencies {
+    let gitProvider: any GitProvider
+    let configurationStore: any ConfigurationStore
+    let metadataStore: any WorkspaceMetadataStore
+    let workspaceManager: any WorkspaceManaging
+    let logger: SaplingLogger
+
+    static func live() -> AppDependencies {
+        let gitProvider = MockGitProvider()
+        let metadataStore = InMemoryWorkspaceMetadataStore()
+        let configurationStore = JSONConfigurationStore(
+            fileURL: supportDirectory().appendingPathComponent("Configuration.json")
+        )
+        let workspaceManager = LocalWorkspaceManager(
+            gitProvider: gitProvider,
+            metadataStore: metadataStore
+        )
+
+        return AppDependencies(
+            gitProvider: gitProvider,
+            configurationStore: configurationStore,
+            metadataStore: metadataStore,
+            workspaceManager: workspaceManager,
+            logger: SaplingLogger()
+        )
+    }
+
+    static func preview() -> AppDependencies {
+        let gitProvider = MockGitProvider()
+        let metadataStore = InMemoryWorkspaceMetadataStore()
+        let configurationStore = InMemoryConfigurationStore()
+        let workspaceManager = LocalWorkspaceManager(
+            gitProvider: gitProvider,
+            metadataStore: metadataStore
+        )
+
+        return AppDependencies(
+            gitProvider: gitProvider,
+            configurationStore: configurationStore,
+            metadataStore: metadataStore,
+            workspaceManager: workspaceManager,
+            logger: SaplingLogger(subsystem: "app.sapling.Sapling.preview")
+        )
+    }
+
+    private static func supportDirectory() -> URL {
+        let baseURL = FileManager.default.urls(
+            for: .applicationSupportDirectory,
+            in: .userDomainMask
+        ).first ?? FileManager.default.temporaryDirectory
+
+        return baseURL.appendingPathComponent("Sapling", isDirectory: true)
+    }
+}

Sources/SaplingApp/SaplingApp.swift

@@ -3,13 +3,14 @@ import SaplingCore
 import SaplingWorkspace
 import SaplingGit
 import SaplingStorage
+import SaplingLogging
 import SaplingEditor
 import SaplingRenderer
 import SaplingUI
 
 @main
 struct SaplingApplication: App {
-    @StateObject private var model = SaplingAppModel()
+    @StateObject private var model = SaplingAppModel(dependencies: .live())
 
     var body: some Scene {
         WindowGroup {
@@ -19,6 +20,15 @@ struct SaplingApplication: App {
         .windowStyle(.titleBar)
         .windowToolbarStyle(.unified)
         #endif
+
+        #if os(macOS)
+        Settings {
+            SettingsView(
+                configuration: $model.configuration,
+                onSave: model.save(configuration:)
+            )
+        }
+        #endif
     }
 }
 
@@ -29,23 +39,27 @@ private final class SaplingAppModel: ObservableObject {
     @Published var selectedDocument: MarkdownDocument?
     @Published var editorViewModel: HybridMarkdownEditorViewModel?
     @Published var gitStatuses: [GitFileStatus] = []
+    @Published var configuration: SaplingConfiguration
 
     private let gitProvider: any GitProvider
+    private let configurationStore: any ConfigurationStore
     private let workspaceManager: any WorkspaceManaging
+    private let logger: SaplingLogger
 
-    init() {
-        let gitProvider = MockGitProvider()
-        self.gitProvider = gitProvider
-        self.workspaceManager = LocalWorkspaceManager(
-            gitProvider: gitProvider,
-            metadataStore: InMemoryWorkspaceMetadataStore()
-        )
+    init(dependencies: AppDependencies) {
+        self.gitProvider = dependencies.gitProvider
+        self.configurationStore = dependencies.configurationStore
+        self.workspaceManager = dependencies.workspaceManager
+        self.logger = dependencies.logger
+        self.configuration = (try? dependencies.configurationStore.loadConfiguration()) ?? SaplingConfiguration()
 
         let workspace = workspaceManager.sampleWorkspace()
         self.workspace = workspace
         self.selectedProject = workspace.firstProject
         setSelectedDocument(SaplingSampleData.document)
 
+        logger.info("Sapling application model initialized", category: .app)
+
         Task {
             await refreshGitStatus()
         }
@@ -67,11 +81,21 @@ private final class SaplingAppModel: ObservableObject {
 
     func select(project: Project) {
         selectedProject = project
+        logger.info("Selected project: \(project.name)", category: .workspace)
         Task {
             await refreshGitStatus()
         }
     }
 
+    func save(configuration: SaplingConfiguration) {
+        do {
+            try configurationStore.saveConfiguration(configuration)
+            logger.debug("Saved configuration", category: .storage)
+        } catch {
+            logger.error("Failed to save configuration: \(error)", category: .storage)
+        }
+    }
+
     private func refreshGitStatus() async {
         guard let selectedProject else {
             gitStatuses = []
@@ -81,16 +105,19 @@ private final class SaplingAppModel: ObservableObject {
         do {
             let repository = gitProvider.repository(at: selectedProject.repositoryURL)
             gitStatuses = try await repository.status()
+            logger.debug("Loaded \(gitStatuses.count) Git status entries", category: .git)
         } catch {
             gitStatuses = [
                 GitFileStatus(path: "Unable to load status: \(error)", state: .conflicted)
             ]
+            logger.error("Failed to refresh Git status: \(error)", category: .git)
         }
     }
 
     private func setSelectedDocument(_ document: MarkdownDocument) {
         selectedDocument = document
         editorViewModel = HybridMarkdownEditorViewModel(document: document)
+        logger.info("Selected document: \(document.title)", category: .editor)
     }
 }
 

Sources/SaplingLogging/SaplingLogger.swift

@@ -0,0 +1,39 @@
+import Foundation
+import OSLog
+
+public struct SaplingLogger: Sendable {
+    public enum Category: String, Sendable {
+        case app
+        case workspace
+        case git
+        case editor
+        case storage
+        case rendering
+    }
+
+    private let subsystem: String
+
+    public init(subsystem: String = "app.sapling.Sapling") {
+        self.subsystem = subsystem
+    }
+
+    public func debug(_ message: String, category: Category) {
+        logger(for: category).debug("\(message, privacy: .public)")
+    }
+
+    public func info(_ message: String, category: Category) {
+        logger(for: category).info("\(message, privacy: .public)")
+    }
+
+    public func warning(_ message: String, category: Category) {
+        logger(for: category).warning("\(message, privacy: .public)")
+    }
+
+    public func error(_ message: String, category: Category) {
+        logger(for: category).error("\(message, privacy: .public)")
+    }
+
+    private func logger(for category: Category) -> Logger {
+        Logger(subsystem: subsystem, category: category.rawValue)
+    }
+}

Sources/SaplingStorage/Configuration.swift

@@ -4,15 +4,21 @@ public struct SaplingConfiguration: Hashable, Codable, Sendable {
     public var recentWorkspaceURLs: [URL]
     public var defaultBranchName: String
     public var autosavesDrafts: Bool
+    public var showsHiddenFiles: Bool
+    public var preferredEditorFontSize: Double
 
     public init(
         recentWorkspaceURLs: [URL] = [],
         defaultBranchName: String = "main",
-        autosavesDrafts: Bool = true
+        autosavesDrafts: Bool = true,
+        showsHiddenFiles: Bool = false,
+        preferredEditorFontSize: Double = 15
     ) {
         self.recentWorkspaceURLs = recentWorkspaceURLs
         self.defaultBranchName = defaultBranchName
         self.autosavesDrafts = autosavesDrafts
+        self.showsHiddenFiles = showsHiddenFiles
+        self.preferredEditorFontSize = preferredEditorFontSize
     }
 }
 
@@ -36,3 +42,34 @@ public final class InMemoryConfigurationStore: ConfigurationStore, @unchecked Se
         self.configuration = configuration
     }
 }
+
+public final class JSONConfigurationStore: ConfigurationStore, @unchecked Sendable {
+    private let fileURL: URL
+    private let encoder: JSONEncoder
+    private let decoder: JSONDecoder
+
+    public init(fileURL: URL) {
+        self.fileURL = fileURL
+        self.encoder = JSONEncoder()
+        self.decoder = JSONDecoder()
+        encoder.outputFormatting = [.prettyPrinted, .sortedKeys]
+    }
+
+    public func loadConfiguration() throws -> SaplingConfiguration {
+        guard FileManager.default.fileExists(atPath: fileURL.path) else {
+            return SaplingConfiguration()
+        }
+
+        let data = try Data(contentsOf: fileURL)
+        return try decoder.decode(SaplingConfiguration.self, from: data)
+    }
+
+    public func saveConfiguration(_ configuration: SaplingConfiguration) throws {
+        try FileManager.default.createDirectory(
+            at: fileURL.deletingLastPathComponent(),
+            withIntermediateDirectories: true
+        )
+        let data = try encoder.encode(configuration)
+        try data.write(to: fileURL, options: [.atomic])
+    }
+}

Sources/SaplingUI/SettingsView.swift

@@ -0,0 +1,47 @@
+import SwiftUI
+import SaplingStorage
+
+public struct SettingsView: View {
+    @Binding private var configuration: SaplingConfiguration
+    private let onSave: (SaplingConfiguration) -> Void
+
+    public init(
+        configuration: Binding<SaplingConfiguration>,
+        onSave: @escaping (SaplingConfiguration) -> Void
+    ) {
+        self._configuration = configuration
+        self.onSave = onSave
+    }
+
+    public var body: some View {
+        Form {
+            Section("General") {
+                TextField("Default branch", text: binding(\.defaultBranchName))
+                Toggle("Autosave drafts", isOn: binding(\.autosavesDrafts))
+                Toggle("Show hidden files", isOn: binding(\.showsHiddenFiles))
+            }
+
+            Section("Editor") {
+                HStack {
+                    Slider(value: binding(\.preferredEditorFontSize), in: 11...24, step: 1)
+                    Text("\(Int(configuration.preferredEditorFontSize)) pt")
+                        .foregroundStyle(.secondary)
+                        .monospacedDigit()
+                }
+            }
+        }
+        .formStyle(.grouped)
+        .frame(minWidth: 420, minHeight: 260)
+        .padding()
+    }
+
+    private func binding<Value>(_ keyPath: WritableKeyPath<SaplingConfiguration, Value>) -> Binding<Value> {
+        Binding(
+            get: { configuration[keyPath: keyPath] },
+            set: { newValue in
+                configuration[keyPath: keyPath] = newValue
+                onSave(configuration)
+            }
+        )
+    }
+}

roadmap.md

@@ -27,7 +27,7 @@ without relying on proprietary services.
 
 # Milestone 0 — Foundation
 
-Status: In Progress
+Status: Complete
 
 Goal: