my solution

lib/jump.ex

@@ -0,0 +1,19 @@
+defmodule Jump do
+
+  @base_url "https://wikimedia.org/api/rest_v1"
+
+  def fetch(article, start, the_end) do
+    url = "/metrics/pageviews/per-article/en.wikipedia.org/all-access/user/#{article}/daily/#{start}/#{the_end}"
+
+    %{body: %{"items" => items}} = Req.get!(req(), url: url)
+    items
+  end
+
+  def post(summary) do
+    Req.post!("https://postman-echo.com/post", body: Jason.encode!(summary))
+  end
+
+  def req do
+    Req.new(base_url: @base_url)
+  end
+end