diff --git a/ft_strjoin.c b/ft_strjoin.c
new file mode 100644
index 0000000..0f87508
--- /dev/null
+++ b/ft_strjoin.c
@@ -0,0 +1,27 @@
+char	*ft_strjoin(char const *s1, char const *s2)
+{
+	char	*dest;
+	int		i;
+	int		j;
+
+	i = 0;
+	j = 0;
+	dest = malloc(sizeof(char) * (ft_strlen(s1) + ft_strlen(s2) + 1));
+	if (dest == 0)
+		return (0);
+	while (s1[i])
+	{
+		dest[j] = s1[i];
+		j++;
+		i++;
+	}
+	i = 0;
+	while(s2[i])
+	{
+		dest[j] = s2[i];
+		j++;
+		i++;
+	}
+	dest[j] = 0;
+	return (dest);
+}
diff --git a/ft_substr.c b/ft_substr.c
new file mode 100644
index 0000000..d4533b3
--- /dev/null
+++ b/ft_substr.c
@@ -0,0 +1,32 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   ft_substr.c                                        :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: apommier <apommier@student.42.fr>          +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2020/11/29 22:54:40 by apommier          #+#    #+#             */
+/*   Updated: 2020/11/29 23:28:20 by apommier         ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include <libft.h>
+
+char	*ft_substr(char const *s, unsigned int start, size_t len)
+{
+	char	*dest;
+	int		i;
+
+	i = 0;
+	dest = malloc(sizeof(char) * len);
+	if (dest == 0)
+		return (0);
+	while (len - 1)
+	{
+		dest[i] = s[i + start];
+		len--;
+		i++;
+	}
+	dest[i] = 0;
+	return (dest);
+}