diff --git a/.gitignore b/.gitignore
index 267eb4d..f9453ef 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,7 +2,6 @@
 *.o
 *.a
 *.so
-labfy-investigation
 
 # SQLite
 *.sqlite-wal
diff --git a/docs/tickets/open/TICKET-001.md b/docs/tickets/open/TICKET-001.md
new file mode 100644
index 0000000..3edd3d3
--- /dev/null
+++ b/docs/tickets/open/TICKET-001.md
@@ -0,0 +1,37 @@
+# Ticket #001
+
+## Titre
+
+Créer le module Application.
+
+## Objectif
+
+Créer le point d’entrée applicatif chargé de gérer le cycle de vie de GTK.
+
+## Responsabilités
+
+- créer l’objet GtkApplication ;
+- lancer la boucle principale GTK ;
+- libérer proprement les ressources ;
+- afficher une fenêtre minimale au signal `activate`.
+
+## Hors périmètre
+
+- SQLite ;
+- ouverture d’une enquête ;
+- sélecteur de dossier ;
+- logique métier.
+
+## Critères d’acceptation
+
+- [ ] Le projet compile en C17.
+- [ ] Aucun warning.
+- [ ] Aucun état global.
+- [ ] Les fonctions publiques sont documentées avec Doxygen.
+- [ ] Une fenêtre GTK minimale s’affiche.
+- [ ] La fermeture de l’application est propre.
+
+## Commit attendu
+
+```text
+feat(core): create application lifecycle
diff --git a/labfy-investigation/.gitignore b/labfy-investigation/.gitignore
new file mode 100644
index 0000000..3fedcb4
--- /dev/null
+++ b/labfy-investigation/.gitignore
@@ -0,0 +1,11 @@
+# Build
+enquete-gui
+*.o
+
+# SQLite temporaires
+*.sqlite-shm
+*.sqlite-wal
+
+# Neovim / LSP
+.cache/
+compile_commands.json
diff --git a/labfy-investigation/Makefile b/labfy-investigation/Makefile
new file mode 100644
index 0000000..6cd3a68
--- /dev/null
+++ b/labfy-investigation/Makefile
@@ -0,0 +1,33 @@
+CC = gcc
+
+PKG_CONFIG = pkg-config
+
+CFLAGS = -std=c17 \
+          -Wall \
+          -Wextra \
+          -Werror \
+          -g \
+          -Iinclude \
+          $(shell $(PKG_CONFIG) --cflags gtk4 sqlite3)
+
+LDFLAGS = $(shell $(PKG_CONFIG) --libs gtk4 sqlite3)
+
+SRC := $(shell find src -name "*.c")
+
+OBJ := $(SRC:.c=.o)
+
+TARGET = labfy-investigation
+
+$(TARGET): $(OBJ)
+	$(CC) $(OBJ) -o $@ $(LDFLAGS)
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+clean:
+	rm -f $(OBJ) $(TARGET)
+
+run: $(TARGET)
+	./$(TARGET)
+
+.PHONY: clean run
diff --git a/labfy-investigation/compile_flags.txt b/labfy-investigation/compile_flags.txt
new file mode 100644
index 0000000..0d77def
--- /dev/null
+++ b/labfy-investigation/compile_flags.txt
@@ -0,0 +1,22 @@
+-I/usr/include/gtk-4.0
+-I/usr/include/pango-1.0
+-I/usr/include/fribidi
+-I/usr/include/harfbuzz
+-I/usr/include/gdk-pixbuf-2.0
+-I/usr/include/glycin-2
+-I/usr/include/cairo
+-I/usr/include/freetype2
+-I/usr/include/libpng16
+-I/usr/include/pixman-1
+-I/usr/include/graphene-1.0
+-I/usr/lib/graphene-1.0/include
+-mfpmath=sse
+-msse
+-msse2
+-I/usr/include/glib-2.0
+-I/usr/lib/glib-2.0/include
+-I/usr/include/libmount
+-I/usr/include/blkid
+-I/usr/include/sysprof-6
+-pthread
+-Iinclude
diff --git a/labfy-investigation/database/init.sql b/labfy-investigation/database/init.sql
new file mode 100644
index 0000000..e69de29
diff --git a/labfy-investigation/database/schema.sql b/labfy-investigation/database/schema.sql
new file mode 100644
index 0000000..e69de29
diff --git a/labfy-investigation/include/core/application.h b/labfy-investigation/include/core/application.h
new file mode 100644
index 0000000..f0c8eeb
--- /dev/null
+++ b/labfy-investigation/include/core/application.h
@@ -0,0 +1,43 @@
+/******************************************************************************
+ * @file application.h
+ * @brief Interface publique du cycle de vie de l'application.
+ ******************************************************************************/
+
+#ifndef LABFY_INVESTIGATION_APPLICATION_H
+#define LABFY_INVESTIGATION_APPLICATION_H
+
+/**
+ * @brief Représentation opaque de l'application.
+ *
+ * Les détails GTK sont volontairement masqués au reste du programme.
+ */
+typedef struct Application Application;
+
+/**
+ * @brief Crée et initialise une application Labfy Investigation.
+ *
+ * @return Une nouvelle application, ou NULL en cas d'échec.
+ */
+Application *application_new(void);
+
+/**
+ * @brief Lance la boucle principale de l'application.
+ *
+ * @param application Application à exécuter.
+ * @param argc Nombre d'arguments de la ligne de commande.
+ * @param argv Tableau des arguments de la ligne de commande.
+ *
+ * @return Code de sortie retourné par GTK.
+ */
+int application_run(Application *application, int argc, char **argv);
+
+/**
+ * @brief Libère les ressources possédées par l'application.
+ *
+ * Cette fonction accepte NULL.
+ *
+ * @param application Application à libérer.
+ */
+void application_free(Application *application);
+
+#endif
diff --git a/labfy-investigation/labfy-investigation b/labfy-investigation/labfy-investigation
new file mode 100755
index 0000000..5c17dac
Binary files /dev/null and b/labfy-investigation/labfy-investigation differ
diff --git a/labfy-investigation/src/core/application.c b/labfy-investigation/src/core/application.c
new file mode 100644
index 0000000..79e6288
--- /dev/null
+++ b/labfy-investigation/src/core/application.c
@@ -0,0 +1,115 @@
+/******************************************************************************
+ * @file application.c
+ * @brief Implémentation du cycle de vie de l'application GTK.
+ ******************************************************************************/
+
+#include "core/application.h"
+
+#include <gtk/gtk.h>
+
+/**
+ * @brief Identifiant unique utilisé par GLib pour l'application.
+ */
+#define APPLICATION_ID "com.labfytools.investigation"
+
+/**
+ * @brief Dimensions initiales de la fenêtre principale.
+ */
+#define DEFAULT_WINDOW_WIDTH 1000
+#define DEFAULT_WINDOW_HEIGHT 650
+
+/**
+ * @struct Application
+ * @brief État interne de l'application.
+ *
+ * Cette structure reste privée à ce module afin d'empêcher les autres
+ * composants de manipuler directement les objets GTK.
+ */
+struct Application
+{
+    GtkApplication *gtk_application;
+};
+
+/**
+ * @brief Crée la fenêtre minimale lors de l'activation de l'application.
+ *
+ * Cette fonction est privée au module. Elle est appelée par GTK lorsque
+ * l'application reçoit le signal "activate".
+ *
+ * @param gtk_application Application GTK ayant reçu le signal.
+ * @param user_data Données utilisateur associées au signal.
+ */
+static void application_on_activate(GtkApplication *gtk_application,
+                                    gpointer user_data)
+{
+    GtkWidget *window = NULL;
+
+    (void)user_data;
+
+    window = gtk_application_window_new(gtk_application);
+
+    gtk_window_set_title(GTK_WINDOW(window), "Labfy Investigation");
+    gtk_window_set_default_size(
+        GTK_WINDOW(window),
+        DEFAULT_WINDOW_WIDTH,
+        DEFAULT_WINDOW_HEIGHT
+    );
+
+    gtk_window_present(GTK_WINDOW(window));
+}
+
+Application *application_new(void)
+{
+    Application *application = NULL;
+
+    application = g_new0(Application, 1);
+
+    application->gtk_application = gtk_application_new(
+        APPLICATION_ID,
+        G_APPLICATION_DEFAULT_FLAGS
+    );
+
+    if (application->gtk_application == NULL)
+    {
+        g_free(application);
+        return NULL;
+    }
+
+    g_signal_connect(
+        application->gtk_application,
+        "activate",
+        G_CALLBACK(application_on_activate),
+        application
+    );
+
+    return application;
+}
+
+int application_run(Application *application, int argc, char **argv)
+{
+    if (application == NULL || application->gtk_application == NULL)
+    {
+        return 1;
+    }
+
+    return g_application_run(
+        G_APPLICATION(application->gtk_application),
+        argc,
+        argv
+    );
+}
+
+void application_free(Application *application)
+{
+    if (application == NULL)
+    {
+        return;
+    }
+
+    if (application->gtk_application != NULL)
+    {
+        g_object_unref(application->gtk_application);
+    }
+
+    g_free(application);
+}
diff --git a/labfy-investigation/src/main.c b/labfy-investigation/src/main.c
new file mode 100644
index 0000000..8ce50aa
--- /dev/null
+++ b/labfy-investigation/src/main.c
@@ -0,0 +1,27 @@
+/******************************************************************************
+ * @file main.c
+ * @brief Point d'entrée de Labfy Investigation.
+ ******************************************************************************/
+
+#include "core/application.h"
+
+#include <stdlib.h>
+
+int main(int argc, char **argv)
+{
+    Application *application = NULL;
+    int exit_status = EXIT_FAILURE;
+
+    application = application_new();
+
+    if (application == NULL)
+    {
+        return EXIT_FAILURE;
+    }
+
+    exit_status = application_run(application, argc, argv);
+
+    application_free(application);
+
+    return exit_status;
+}