diff --git a/include/minishell.h b/include/minishell.h
index 11b7bf7..d76c2a0 100644
--- a/include/minishell.h
+++ b/include/minishell.h
@@ -6,7 +6,7 @@
 /*   By: sede-san <sede-san@student.42madrid.com    +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2025/10/20 16:35:10 by sede-san          #+#    #+#             */
-/*   Updated: 2025/10/20 20:20:30 by sede-san         ###   ########.fr       */
+/*   Updated: 2025/10/22 16:59:56 by sede-san         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -36,4 +36,24 @@
 # include <term.h>				// tgetent(3), tgetflag(3), tgetnum(3),
 								// tgetstr(3), tgoto(3), tputs(3)
 
+/******************************************************************************/
+/*                           Structures & Data Types                          */
+/******************************************************************************/
+
+typedef struct s_minishell	t_minishell;
+
+typedef struct s_minishell
+{
+	char			**env;
+	u_int8_t		exit_status;
+}	t_minishell;
+
+/* core/minishell.c */
+
+extern int		minishell_init(struct s_minishell *minishell, char **envp);
+
+extern u_int8_t	minishell_run(struct s_minishell *minishell);
+
+extern void		minishell_clear(struct s_minishell *minishell);
+
 #endif /* MINISHELL_H */
diff --git a/src/.gitkeep b/src/.gitkeep
deleted file mode 100644
index e69de29..0000000
diff --git a/src/core/minishell.c b/src/core/minishell.c
new file mode 100644
index 0000000..2139aa6
--- /dev/null
+++ b/src/core/minishell.c
@@ -0,0 +1,45 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   minishell.c                                        :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: sede-san <sede-san@student.42madrid.com    +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2025/10/20 20:51:33 by sede-san          #+#    #+#             */
+/*   Updated: 2025/10/22 17:02:52 by sede-san         ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "minishell.h"
+
+int	minishell_init(
+	t_minishell	*minishell,
+	char		**envp
+){
+	ft_bzero(minishell, sizeof(t_minishell));
+	minishell->env = envp;
+	return (1);
+}
+
+u_int8_t	minishell_run(
+	t_minishell	*minishell
+){
+	char	*line;
+
+	while (1)
+	{
+		line = readline("minishell > ");
+		if (!ft_strcmp(line, "exit"))
+			break ;
+		printf("%s\n", line);
+		free(line);
+	}
+	free(line);
+	return (minishell->exit_status);
+}
+
+void	minishell_clear(
+	t_minishell	*minishell
+){
+	ft_bzero(minishell, sizeof(t_minishell));
+}
diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..175ac78
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,36 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   main.c                                             :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: sede-san <sede-san@student.42madrid.com    +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2025/10/20 16:34:42 by sede-san          #+#    #+#             */
+/*   Updated: 2025/10/22 16:58:08 by sede-san         ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "minishell.h"
+
+int	main(
+	int argc,
+	char const *argv[],
+	char **envp
+){
+	t_minishell	minishell;
+	u_int8_t	exit_status;
+
+	if (argc != 1 || argv[1] || !envp)
+	{
+		printf("Usage: ./minishell\n");
+		return (EXIT_FAILURE);
+	}
+	if (!minishell_init(&minishell, envp))
+	{
+		printf("Error: %s\n", "failed to initialize minishell");
+		return (EXIT_FAILURE);
+	}
+	exit_status = minishell_run(&minishell);
+	minishell_clear(&minishell);
+	return (exit_status);
+}