diff --git a/scripts/gen-centered-graph.py b/scripts/gen-centered-graph.py
deleted file mode 100644
index ef4ff18..0000000
--- a/scripts/gen-centered-graph.py
+++ /dev/null
@@ -1,125 +0,0 @@
-import requests
-import sys
-
-url = 'http://localhost:8000/notes/graph.json'
-reference_node = sys.argv[1]
-out = sys.argv[2]
-
-g = requests.get(url).json()
-centered_graph = { reference_node: g[reference_node] }
-del g[reference_node]
-new_nodes = True
-
-in_emacs_tree = {
-    reference_node: set(),
-}
-
-while new_nodes:
-    new_nodes = False
-    removed = set()
-    for k, v in g.items():
-        for link in v["links"]:
-            if link["target"].startswith("id:"):
-                link["target"] = link["target"][3:]
-            if link['target'] in centered_graph and link.get('relation') == 'in':
-                centered_graph[k] = v
-
-                for l in v["links"]:
-                    if l.get('relation') == 'in':
-                        t = l['target']
-                        if t.startswith("id:"):
-                            t = t[3:]
-
-                        if '[' in t:
-                            # Special case, to be handled on org_rw
-                            continue
-
-                        if t not in in_emacs_tree:
-                            in_emacs_tree[t] = set()
-                        in_emacs_tree[t].add(k)
-
-                v['links'] = [
-                    l for l in v["links"]
-                    if l.get('relation') != 'in'
-                ]
-
-
-                removed.add(k)
-                new_nodes = True
-                break
-    for k in removed:
-        del g[k]
-
-in_emacs = set(centered_graph.keys())
-
-
-# One more round for the rest, not requiring "in"
-for k, v in g.items():
-    for link in v["links"]:
-        if link["target"].startswith("id:"):
-            link["target"] = link["target"][3:]
-        if link['target'] in in_emacs:
-            centered_graph[k] = v
-            removed.add(k)
-
-g = centered_graph
-
-f = open('graph.dot', 'wt')
-f.write('digraph {\n')
-# f.write('bgcolor="#222222"\n')
-# f.write('fontcolor="#ffffff"\n')
-f.write('maxiter=1000\n')
-f.write('splines=curved\n')
-# f.write('splines=spline\n') # Not supported with edges to cluster
-f.write('node[shape=rect]\n')
-# f.write('edge[color="#ffffff"]\n')
-
-def draw_subgraph(node_id):
-    f.write("subgraph cluster_{} {{\n".format(node_id.replace("-", "_")))
-    f.write('URL="./{}.node.html"\n'.format(node_id))
-    # f.write('color="#ffffff"\n')
-
-    f.write("label=\"{}\"\n".format(g[node_id]['title'].replace("\"", "'")))
-    f.write("\n")
-
-    # print("T: {}".format(in_emacs_tree), file=sys.stderr)
-    for k in in_emacs_tree[node_id]:
-        v = g[k]
-        print("_" + k.replace("-", "_") + "[label=\"" + v["title"].replace("\"", "'") + "\", URL=\"" + k + ".node.html\"];", file=f)
-
-        if k in in_emacs_tree:
-            draw_subgraph(k)
-
-    f.write("\n}")
-
-draw_subgraph(reference_node)
-
-for k, v in g.items():
-    if k not in in_emacs:
-        print("_" + k.replace("-", "_") + "[label=\"" + v["title"].replace("\"", "'") + "\", URL=\"" + k + ".node.html\"];", file=f)
-
-for k, v in g.items():
-    for link in v["links"]:
-        if link["target"].startswith("id:"):
-            link["target"] = link["target"][3:]
-
-        if '[' in link['target']:
-            # Special case, to be handled on org_rw
-            continue
-        if link['target'] not in g:
-            # Irrelevant
-            continue
-        if link['target'] in in_emacs_tree:
-            t = 'cluster_{}'.format(link['target'].replace("-", "_"))
-        else:
-            t = "_" + link["target"].replace("-", "_")
-        print("_" + k.replace("-", "_") + "->" + t, file=f)
-
-f.write('}\n')
-# dot graph.dot -Tsvg graph.svg
-
-f.close()
-
-import subprocess
-subprocess.call("fdp graph.dot -Tsvg -o '{}'".format(out), shell=True)
-# return "graph.svg"
diff --git a/scripts/gen_centered_graph.py b/scripts/gen_centered_graph.py
new file mode 100644
index 0000000..8176e16
--- /dev/null
+++ b/scripts/gen_centered_graph.py
@@ -0,0 +1,126 @@
+import requests
+import sys
+import subprocess
+import ops_cache
+import copy
+import tempfile
+
+# TODO: Cache results
+# TODO: Properly render outgouing links
+
+# @ops_cache()
+def gen(headline_id, graph):
+    reference_node = headline_id
+
+    g = copy.deepcopy(graph)
+    centered_graph = { reference_node: g[reference_node] }
+    del g[reference_node]
+    new_nodes = True
+
+    in_emacs_tree = {
+        reference_node: set(),
+    }
+
+    while new_nodes:
+        new_nodes = False
+        removed = set()
+        for k, v in g.items():
+            for link in v["links"]:
+                if link["target"].startswith("id:"):
+                    link["target"] = link["target"][3:]
+                if link['target'] in centered_graph and link.get('relation') == 'in':
+                    centered_graph[k] = v
+
+                    for l in v["links"]:
+                        if l.get('relation') == 'in':
+                            t = l['target']
+                            if t.startswith("id:"):
+                                t = t[3:]
+
+                            if '[' in t:
+                                # Special case, to be handled on org_rw
+                                continue
+
+                            if t not in in_emacs_tree:
+                                in_emacs_tree[t] = set()
+                            in_emacs_tree[t].add(k)
+
+                    v['links'] = [
+                        l for l in v["links"]
+                        if l.get('relation') != 'in'
+                    ]
+
+
+                    removed.add(k)
+                    new_nodes = True
+                    break
+        for k in removed:
+            del g[k]
+
+    in_emacs = set(centered_graph.keys())
+
+    # One more round for the rest, not requiring "in"
+    for k, v in g.items():
+        for link in v["links"]:
+            if link["target"].startswith("id:"):
+                link["target"] = link["target"][3:]
+            if link['target'] in in_emacs:
+                centered_graph[k] = v
+                removed.add(k)
+
+    g = centered_graph
+
+    with tempfile.NamedTemporaryFile(suffix='.dot', mode='wt') as f:
+        f.write('digraph {\n')
+        f.write('maxiter=1000\n')
+        f.write('splines=curved\n')
+        # f.write('splines=spline\n') # Not supported with edges to cluster
+        f.write('node[shape=rect]\n')
+
+        def draw_subgraph(node_id):
+            f.write("subgraph cluster_{} {{\n".format(node_id.replace("-", "_")))
+            f.write('URL="./{}.node.html"\n'.format(node_id))
+
+            f.write("label=\"{}\"\n".format(g[node_id]['title'].replace("\"", "'")))
+            f.write("\n")
+
+            # print("T: {}".format(in_emacs_tree), file=sys.stderr)
+            for k in in_emacs_tree[node_id]:
+                v = g[k]
+                print("_" + k.replace("-", "_") + "[label=\"" + v["title"].replace("\"", "'") + "\", URL=\"" + k + ".node.html\"];", file=f)
+
+                if k in in_emacs_tree:
+                    draw_subgraph(k)
+
+            f.write("\n}")
+
+        draw_subgraph(reference_node)
+
+        for k, v in g.items():
+            if k not in in_emacs:
+                print("_" + k.replace("-", "_") + "[label=\"" + v["title"].replace("\"", "'") + "\", URL=\"" + k + ".node.html\"];", file=f)
+
+        for k, v in g.items():
+            for link in v["links"]:
+                if link["target"].startswith("id:"):
+                    link["target"] = link["target"][3:]
+
+                if '[' in link['target']:
+                    # Special case, to be handled on org_rw
+                    continue
+                if link['target'] not in g:
+                    # Irrelevant
+                    continue
+                if link['target'] in in_emacs_tree:
+                    t = 'cluster_{}'.format(link['target'].replace("-", "_"))
+                else:
+                    t = "_" + link["target"].replace("-", "_")
+                print("_" + k.replace("-", "_") + "->" + t, file=f)
+
+        f.write('}\n')
+        f.close()
+
+        with tempfile.NamedTemporaryFile(suffix='.svg') as fsvg:
+            subprocess.call("fdp graph.dot -Tsvg -o '{}'".format(fsvg.name), shell=True)
+            fsvg.seek(0)
+            return fsvg.read().decode()
diff --git a/scripts/generate.py b/scripts/generate.py
index 026a960..c6ecc3d 100644
--- a/scripts/generate.py
+++ b/scripts/generate.py
@@ -25,6 +25,7 @@ from org_rw import token_list_to_raw
 import pygments
 import pygments.lexers
 import pygments.formatters
+import gen_centered_graph
 
 # Set custom states
 for state in ("NEXT", "MEETING", "Q", "PAUSED", "SOMETIME", "TRACK", "WAITING"):
@@ -710,19 +711,9 @@ def render_connections(headline_id, content, graph):
     # if headline_id != 'aa29be89-70e7-4465-91ed-361cf0ce62f2':
     #     return
 
-    # TODO: Cache results
-    # TODO: Avoid querying graph API on script
-    # TODO: Properly render outgouing links
     logging.info("Generating centered graph for {}".format(headline_id))
-    import subprocess
-    this_dir = os.path.dirname(os.path.abspath(__file__))
-    os.makedirs('cache', exist_ok=True)
-    subprocess.check_call(['python3', os.path.join(this_dir, 'gen-centered-graph.py'), headline_id, 'cache/' + headline_id + '.svg'])
-    try:
-        with open('cache/' + headline_id + '.svg') as f:
-            content.append("<div class='connections'>{}</div>".format(f.read()))
-    except FileNotFoundError:
-        logging.exception('Graph file not produced on headline: "{}"'.format(headline_id))
+    svg = gen_centered_graph.gen(headline_id, graph['nodes'])
+    content.append("<div class='connections'>{}</div>".format(svg))
 
 def render(headline, doc, graph, headlineLevel):
     try:
diff --git a/scripts/ops_cache.py b/scripts/ops_cache.py
new file mode 100644
index 0000000..e69de29