diff --git a/2023/day9/part1.py b/2023/day9/part1.py
new file mode 100644
index 0000000..df044bb
--- /dev/null
+++ b/2023/day9/part1.py
@@ -0,0 +1,27 @@
+import sys
+from pprint import pprint
+from functools import reduce
+
+maps = []
+
+with open(sys.argv[1]) as file:
+    for line in file:
+        maps.append([int(x) for x in line.rstrip().split(' ')])
+
+def calc(line):
+    diff = []
+    for i in range(0,len(line)-1):
+        diff.append(line[i+1]-line[i])
+    if not all(v == 0 for v in diff):
+        last.append(diff[-1])
+        calc(diff)
+    return 0
+result = [] 
+for mdx,m in enumerate(maps):
+    last = []
+    last.append(m[-1])
+    last.append(calc(m))
+    result.append(reduce(lambda x, y: x+y, last))
+
+print(sum(result))
+
diff --git a/2023/day9/t2 b/2023/day9/t2
new file mode 100644
index 0000000..c7b0638
--- /dev/null
+++ b/2023/day9/t2
@@ -0,0 +1 @@
+0 3 6 9 12 15