diff --git a/corpus/README.md b/corpus/README.md
new file mode 100644
index 0000000..875c15f
--- /dev/null
+++ b/corpus/README.md
@@ -0,0 +1,15 @@
+# .fls-Korpus
+
+Projektdateien, an denen Lesen und Schreiben gemessen werden. Alle GPL.
+
+| Ordner | Herkunft |
+| --- | --- |
+| `java-examples/` | `gitlab.com/filius1/filius`, `beispiele/` @ `6640354` (Filius 2.14.0) |
+| `java-tests/` | ebenda, `src/test/resources/` |
+| `ipad-fixtures/` | `filius-ipad`, `ios/FiliusPadTests/Fixtures/FLS/` @ `3b5ded0` |
+
+`corpus.swift.json` schreibt das Swift-Orakel (`npm run oracle`): was der
+Swift-Leser aus jeder Datei macht. **Swift ist hier kein Schiedsrichter** —
+er verwirft den Java-Gateway unter der Beschriftung `Heimrouter` samt seinen
+Kabeln und Geräte, deren Position XMLEncoder über eine Rückverweis-Kette
+schreibt (s. Plan §13, M2). Schiedsrichter für das Dateiformat ist Java.
diff --git a/corpus/corpus.swift.json b/corpus/corpus.swift.json
new file mode 100644
index 0000000..61ca08f
--- /dev/null
+++ b/corpus/corpus.swift.json
@@ -0,0 +1,427 @@
+{
+  "ipad-fixtures\/dns_server.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 2,
+      "notebook" : 1,
+      "pc" : 5
+    },
+    "links" : 7,
+    "nodes" : 8,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.0-SNAPSHOT (11.03.2012)",
+    "warnings" : [
+
+    ]
+  },
+  "ipad-fixtures\/Public_and_Private_Networks_2_EN.fls" : {
+    "documentation" : 12,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 2,
+      "pc" : 2,
+      "router" : 1
+    },
+    "links" : 4,
+    "nodes" : 6,
+    "residual" : 0,
+    "skipped" : 1,
+    "version" : "Filius version: 2.9.4 (20.07.2025)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS cable 1: unresolved port references 'Port1' and 'Port3'",
+      "Skipped FILIUS cable 4: unresolved port references 'Port9' and 'Port2'"
+    ]
+  },
+  "ipad-fixtures\/zwei_rechnernetze_komplett.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 2,
+      "notebook" : 2,
+      "pc" : 1,
+      "router" : 1
+    },
+    "links" : 5,
+    "nodes" : 6,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.3.1.3 (29. Januar 2011)",
+    "warnings" : [
+
+    ]
+  },
+  "java-examples\/anwendung_komplett.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 2,
+      "pc" : 1
+    },
+    "links" : 3,
+    "nodes" : 4,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 2.1.0 (11.10.2022)",
+    "warnings" : [
+
+    ]
+  },
+  "java-examples\/dhcp_test_scenario.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 3,
+      "pc" : 2
+    },
+    "links" : 3,
+    "nodes" : 6,
+    "residual" : 0,
+    "skipped" : 1,
+    "version" : "Filius version: 2.8.0 (15.03.2025)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS cable 4: unresolved port references 'Port6' and 'Port8'",
+      "Skipped FILIUS cable 5: unresolved port references 'Port9' and 'Port7'"
+    ]
+  },
+  "java-examples\/dns_server.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 2,
+      "notebook" : 1,
+      "pc" : 5
+    },
+    "links" : 7,
+    "nodes" : 8,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.0-SNAPSHOT (11.03.2012)",
+    "warnings" : [
+
+    ]
+  },
+  "java-examples\/einfaches_rechnernetz_komplett.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 3,
+      "notebook" : 4,
+      "pc" : 5
+    },
+    "links" : 11,
+    "nodes" : 12,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.4.5 (04.11.2012)",
+    "warnings" : [
+
+    ]
+  },
+  "java-examples\/email_komplett.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 4,
+      "pc" : 4
+    },
+    "links" : 8,
+    "nodes" : 9,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : null,
+    "warnings" : [
+      "Email Client on 'Rechner 3' has inconsistent kontoListe map entry #2; account bean values remain authoritative.",
+      "Email Client on 'Rechner 3' ignored duplicate kontoListe account entry #2.",
+      "Email Client on 'Rechner 3' ignored duplicate kontoListe account entry #3.",
+      "Email Client on 'Rechner 4' ignored duplicate kontoListe account entry #2.",
+      "Email Client on 'Rechner 1' ignored duplicate kontoListe account entry #2.",
+      "Email Client on 'Rechner 2' ignored duplicate kontoListe account entry #2."
+    ]
+  },
+  "java-examples\/Internet_Complete_with_e-Mail_Webserver_Intranet_Portforwarding_Firewall_DHCP_EN.fls" : {
+    "documentation" : 11,
+    "kinds" : {
+      "networkSwitch" : 3,
+      "notebook" : 5,
+      "pc" : 6,
+      "router" : 7
+    },
+    "links" : 20,
+    "nodes" : 21,
+    "residual" : 0,
+    "skipped" : 4,
+    "version" : "Filius version: 2.9.4 (20.07.2025)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS node with missing bounds coordinates",
+      "Skipped FILIUS node with missing bounds coordinates",
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped malformed Java GUIDocuItem with missing type or geometry.",
+      "Skipped malformed Java GUIDocuItem with missing type or geometry.",
+      "Skipped malformed Java GUIDocuItem with missing type or geometry.",
+      "Skipped FILIUS cable 13: unresolved port references 'Port35' and 'Port39'",
+      "Skipped FILIUS cable 14: unresolved port references 'Port36' and 'Port40'",
+      "Skipped FILIUS cable 18: unresolved port references 'Port44' and 'Port7'",
+      "Skipped FILIUS cable 19: unresolved port references 'Port45' and 'Port5'",
+      "Skipped FILIUS cable 24: unresolved port references 'Port32' and 'Port50'",
+      "Skipped FILIUS cable 26: unresolved port references 'Port34' and 'Port33'"
+    ]
+  },
+  "java-examples\/Internet_Komplett_mit_eMail_Webserver_Intranet_Portforwarding_Firewall_DHCP_DE.fls" : {
+    "documentation" : 9,
+    "kinds" : {
+      "networkSwitch" : 3,
+      "notebook" : 4,
+      "pc" : 6,
+      "router" : 7
+    },
+    "links" : 19,
+    "nodes" : 20,
+    "residual" : 0,
+    "skipped" : 5,
+    "version" : "Filius version: 2.9.4 (20.07.2025)",
+    "warnings" : [
+      "Skipped FILIUS node with missing bounds coordinates",
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS node with missing bounds coordinates",
+      "Skipped FILIUS node with missing bounds coordinates",
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped malformed Java GUIDocuItem with missing type or geometry.",
+      "Skipped malformed Java GUIDocuItem with missing type or geometry.",
+      "Skipped malformed Java GUIDocuItem with missing type or geometry.",
+      "Skipped FILIUS cable 2: unresolved port references 'Port2' and 'Port6'",
+      "Skipped FILIUS cable 13: unresolved port references 'Port34' and 'Port33'",
+      "Skipped FILIUS cable 14: unresolved port references 'Port35' and 'Port39'",
+      "Skipped FILIUS cable 15: unresolved port references 'Port36' and 'Port40'",
+      "Skipped FILIUS cable 19: unresolved port references 'Port44' and 'Port7'",
+      "Skipped FILIUS cable 20: unresolved port references 'Port45' and 'Port5'",
+      "Skipped FILIUS cable 26: unresolved port references 'Port51' and 'Port32'"
+    ]
+  },
+  "java-examples\/internetwork_komplett.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 4,
+      "notebook" : 3,
+      "pc" : 3,
+      "router" : 3
+    },
+    "links" : 12,
+    "nodes" : 13,
+    "residual" : 0,
+    "skipped" : 1,
+    "version" : "Filius version: 2.1.0 (11.10.2022)",
+    "warnings" : [
+      "Skipped FILIUS node with missing bounds coordinates",
+      "Skipped FILIUS cable 1: unresolved port references 'Port17' and 'Port0'"
+    ]
+  },
+  "java-examples\/man-in-the-middle.fls" : {
+    "documentation" : 3,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 3,
+      "pc" : 3
+    },
+    "links" : 6,
+    "nodes" : 7,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 2.5.1 (23.10.2023)",
+    "warnings" : [
+
+    ]
+  },
+  "java-examples\/modem_beispiel.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "notebook" : 1,
+      "pc" : 1,
+      "remoteLink" : 2
+    },
+    "links" : 2,
+    "nodes" : 4,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.5.4 (08.12.2013)",
+    "warnings" : [
+      "Imported Java Modem 'Modem (Zugreifend)' as Remote Link pair 'java-modem-port-12345' (mode=CLIENT [2], ip=localhost, port=12345); host socket transport was replaced by deterministic in-project pairing by normalized port, and cross-host identity is not preserved.",
+      "Imported Java Modem 'Modem (Zugangspunkt)' as Remote Link pair 'java-modem-port-12345' (mode=SERVER [1], ip=localhost, port=12345); host socket transport was replaced by deterministic in-project pairing by normalized port, and cross-host identity is not preserved."
+    ]
+  },
+  "java-examples\/multicast_server.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 2,
+      "pc" : 1
+    },
+    "links" : 3,
+    "nodes" : 4,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 2.4.1 (07.06.2023)",
+    "warnings" : [
+
+    ]
+  },
+  "java-examples\/nat_with_mapped_port.fls" : {
+    "documentation" : 9,
+    "kinds" : {
+      "networkSwitch" : 4,
+      "notebook" : 3,
+      "pc" : 3,
+      "router" : 3
+    },
+    "links" : 10,
+    "nodes" : 13,
+    "residual" : 0,
+    "skipped" : 2,
+    "version" : "Filius version: 2.8.0 (15.03.2025)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS cable 8: unresolved port references 'Port2' and 'Port24'",
+      "Skipped FILIUS cable 9: unresolved port references 'Port23' and 'Port6'",
+      "Skipped FILIUS cable 10: unresolved port references 'Port19' and 'Port22'",
+      "Skipped FILIUS cable 11: unresolved port references 'Port21' and 'Port11'"
+    ]
+  },
+  "java-examples\/nat.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 1,
+      "pc" : 1
+    },
+    "links" : 1,
+    "nodes" : 3,
+    "residual" : 0,
+    "skipped" : 1,
+    "version" : "Filius version: 2.5.1 (23.10.2023)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS cable 1: unresolved port references 'Port2' and 'Port1'",
+      "Skipped FILIUS cable 2: unresolved port references 'Port0' and 'Port4'"
+    ]
+  },
+  "java-examples\/private_and_public_network.fls" : {
+    "documentation" : 7,
+    "kinds" : {
+      "networkSwitch" : 2,
+      "notebook" : 2,
+      "pc" : 1
+    },
+    "links" : 3,
+    "nodes" : 5,
+    "residual" : 0,
+    "skipped" : 1,
+    "version" : "Filius version: 2.5.1 (23.10.2023)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS cable 1: unresolved port references 'Port0' and 'Port6'",
+      "Skipped FILIUS cable 2: unresolved port references 'Port7' and 'Port5'"
+    ]
+  },
+  "java-examples\/private_und_public_networks_mit_provider_DE.fls" : {
+    "documentation" : 10,
+    "kinds" : {
+      "networkSwitch" : 2,
+      "notebook" : 2,
+      "pc" : 3,
+      "router" : 2
+    },
+    "links" : 7,
+    "nodes" : 9,
+    "residual" : 0,
+    "skipped" : 1,
+    "version" : "Filius version: 2.9.4 (20.07.2025)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS cable 1: unresolved port references 'Port0' and 'Port6'",
+      "Skipped FILIUS cable 2: unresolved port references 'Port7' and 'Port5'"
+    ]
+  },
+  "java-examples\/Public_and_Private_Networks_2_EN.fls" : {
+    "documentation" : 12,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 2,
+      "pc" : 2,
+      "router" : 1
+    },
+    "links" : 4,
+    "nodes" : 6,
+    "residual" : 0,
+    "skipped" : 1,
+    "version" : "Filius version: 2.9.4 (20.07.2025)",
+    "warnings" : [
+      "Skipped unsupported FILIUS node type 'Heimrouter' in konfiguration.xml",
+      "Skipped FILIUS cable 1: unresolved port references 'Port1' and 'Port3'",
+      "Skipped FILIUS cable 4: unresolved port references 'Port9' and 'Port2'"
+    ]
+  },
+  "java-examples\/webserver.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 1,
+      "notebook" : 1,
+      "pc" : 1
+    },
+    "links" : 2,
+    "nodes" : 3,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.5.1 (13.02.2013)",
+    "warnings" : [
+
+    ]
+  },
+  "java-examples\/zwei_rechnernetze_komplett.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 2,
+      "notebook" : 2,
+      "pc" : 1,
+      "router" : 1
+    },
+    "links" : 5,
+    "nodes" : 6,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.3.1.3 (29. Januar 2011)",
+    "warnings" : [
+
+    ]
+  },
+  "java-tests\/einfaches_rechnernetz_komplett.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+      "networkSwitch" : 3,
+      "notebook" : 4,
+      "pc" : 5
+    },
+    "links" : 11,
+    "nodes" : 12,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.4.5 (04.11.2012)",
+    "warnings" : [
+
+    ]
+  },
+  "java-tests\/empty.fls" : {
+    "documentation" : 0,
+    "kinds" : {
+
+    },
+    "links" : 0,
+    "nodes" : 0,
+    "residual" : 0,
+    "skipped" : 0,
+    "version" : "Filius version: 1.9.0 (02.05.2020)",
+    "warnings" : [
+
+    ]
+  }
+}
diff --git a/corpus/ipad-fixtures/Public_and_Private_Networks_2_EN.fls b/corpus/ipad-fixtures/Public_and_Private_Networks_2_EN.fls
new file mode 100644
index 0000000..113c240
Binary files /dev/null and b/corpus/ipad-fixtures/Public_and_Private_Networks_2_EN.fls differ
diff --git a/corpus/ipad-fixtures/dns_server.fls b/corpus/ipad-fixtures/dns_server.fls
new file mode 100644
index 0000000..764f41e
Binary files /dev/null and b/corpus/ipad-fixtures/dns_server.fls differ
diff --git a/corpus/ipad-fixtures/zwei_rechnernetze_komplett.fls b/corpus/ipad-fixtures/zwei_rechnernetze_komplett.fls
new file mode 100644
index 0000000..1d48ce0
Binary files /dev/null and b/corpus/ipad-fixtures/zwei_rechnernetze_komplett.fls differ
diff --git a/corpus/java-examples/Internet_Complete_with_e-Mail_Webserver_Intranet_Portforwarding_Firewall_DHCP_EN.fls b/corpus/java-examples/Internet_Complete_with_e-Mail_Webserver_Intranet_Portforwarding_Firewall_DHCP_EN.fls
new file mode 100644
index 0000000..b9be011
Binary files /dev/null and b/corpus/java-examples/Internet_Complete_with_e-Mail_Webserver_Intranet_Portforwarding_Firewall_DHCP_EN.fls differ
diff --git a/corpus/java-examples/Internet_Komplett_mit_eMail_Webserver_Intranet_Portforwarding_Firewall_DHCP_DE.fls b/corpus/java-examples/Internet_Komplett_mit_eMail_Webserver_Intranet_Portforwarding_Firewall_DHCP_DE.fls
new file mode 100644
index 0000000..0055af2
Binary files /dev/null and b/corpus/java-examples/Internet_Komplett_mit_eMail_Webserver_Intranet_Portforwarding_Firewall_DHCP_DE.fls differ
diff --git a/corpus/java-examples/Public_and_Private_Networks_2_EN.fls b/corpus/java-examples/Public_and_Private_Networks_2_EN.fls
new file mode 100644
index 0000000..113c240
Binary files /dev/null and b/corpus/java-examples/Public_and_Private_Networks_2_EN.fls differ
diff --git a/corpus/java-examples/anwendung_komplett.fls b/corpus/java-examples/anwendung_komplett.fls
new file mode 100644
index 0000000..38ad78c
Binary files /dev/null and b/corpus/java-examples/anwendung_komplett.fls differ
diff --git a/corpus/java-examples/dhcp_test_scenario.fls b/corpus/java-examples/dhcp_test_scenario.fls
new file mode 100644
index 0000000..406cd14
Binary files /dev/null and b/corpus/java-examples/dhcp_test_scenario.fls differ
diff --git a/corpus/java-examples/dns_server.fls b/corpus/java-examples/dns_server.fls
new file mode 100644
index 0000000..764f41e
Binary files /dev/null and b/corpus/java-examples/dns_server.fls differ
diff --git a/corpus/java-examples/einfaches_rechnernetz_komplett.fls b/corpus/java-examples/einfaches_rechnernetz_komplett.fls
new file mode 100644
index 0000000..cfddffe
Binary files /dev/null and b/corpus/java-examples/einfaches_rechnernetz_komplett.fls differ
diff --git a/corpus/java-examples/email_komplett.fls b/corpus/java-examples/email_komplett.fls
new file mode 100644
index 0000000..6c8190a
Binary files /dev/null and b/corpus/java-examples/email_komplett.fls differ
diff --git a/corpus/java-examples/internetwork_komplett.fls b/corpus/java-examples/internetwork_komplett.fls
new file mode 100644
index 0000000..53dcc39
Binary files /dev/null and b/corpus/java-examples/internetwork_komplett.fls differ
diff --git a/corpus/java-examples/man-in-the-middle.fls b/corpus/java-examples/man-in-the-middle.fls
new file mode 100644
index 0000000..1c0ebfa
Binary files /dev/null and b/corpus/java-examples/man-in-the-middle.fls differ
diff --git a/corpus/java-examples/modem_beispiel.fls b/corpus/java-examples/modem_beispiel.fls
new file mode 100644
index 0000000..bdf4a55
Binary files /dev/null and b/corpus/java-examples/modem_beispiel.fls differ
diff --git a/corpus/java-examples/multicast_server.fls b/corpus/java-examples/multicast_server.fls
new file mode 100644
index 0000000..3d718d6
Binary files /dev/null and b/corpus/java-examples/multicast_server.fls differ
diff --git a/corpus/java-examples/nat.fls b/corpus/java-examples/nat.fls
new file mode 100644
index 0000000..26f625a
Binary files /dev/null and b/corpus/java-examples/nat.fls differ
diff --git a/corpus/java-examples/nat_with_mapped_port.fls b/corpus/java-examples/nat_with_mapped_port.fls
new file mode 100644
index 0000000..7e9b25c
Binary files /dev/null and b/corpus/java-examples/nat_with_mapped_port.fls differ
diff --git a/corpus/java-examples/private_and_public_network.fls b/corpus/java-examples/private_and_public_network.fls
new file mode 100644
index 0000000..92999b8
Binary files /dev/null and b/corpus/java-examples/private_and_public_network.fls differ
diff --git a/corpus/java-examples/private_und_public_networks_mit_provider_DE.fls b/corpus/java-examples/private_und_public_networks_mit_provider_DE.fls
new file mode 100644
index 0000000..92ce2a0
Binary files /dev/null and b/corpus/java-examples/private_und_public_networks_mit_provider_DE.fls differ
diff --git a/corpus/java-examples/webserver.fls b/corpus/java-examples/webserver.fls
new file mode 100644
index 0000000..1fa285c
Binary files /dev/null and b/corpus/java-examples/webserver.fls differ
diff --git a/corpus/java-examples/zwei_rechnernetze_komplett.fls b/corpus/java-examples/zwei_rechnernetze_komplett.fls
new file mode 100644
index 0000000..1d48ce0
Binary files /dev/null and b/corpus/java-examples/zwei_rechnernetze_komplett.fls differ
diff --git a/corpus/java-tests/einfaches_rechnernetz_komplett.fls b/corpus/java-tests/einfaches_rechnernetz_komplett.fls
new file mode 100644
index 0000000..cfddffe
Binary files /dev/null and b/corpus/java-tests/einfaches_rechnernetz_komplett.fls differ
diff --git a/corpus/java-tests/empty.fls b/corpus/java-tests/empty.fls
new file mode 100644
index 0000000..922444d
Binary files /dev/null and b/corpus/java-tests/empty.fls differ
diff --git a/tools/swift-oracle/Sources/Oracle/main.swift b/tools/swift-oracle/Sources/Oracle/main.swift
index e89a26c..5037862 100644
--- a/tools/swift-oracle/Sources/Oracle/main.swift
+++ b/tools/swift-oracle/Sources/Oracle/main.swift
@@ -257,8 +257,50 @@ func run(_ scenario: Scenario) -> JSON {
     ]
 }
 
+// MARK: - .fls corpus
+
+/// Imports every .fls under `root` and summarizes what the Swift reader made of it.
+func readCorpus(root: URL) throws -> JSON {
+    var result: JSON = [:]
+    let enumerator = FileManager.default.enumerator(at: root, includingPropertiesForKeys: nil)
+    var files: [URL] = []
+    while let item = enumerator?.nextObject() as? URL {
+        if item.pathExtension == "fls" { files.append(item) }
+    }
+    for file in files.sorted(by: { $0.path < $1.path }) {
+        let name = String(file.path.dropFirst(root.path.count + 1))
+        do {
+            let imported = try TopologyProjectStore.importFiliusArchive(Data(contentsOf: file))
+            let state = imported.state
+            var kinds: [String: Int] = [:]
+            for node in state.graph.nodes { kinds[node.kind.rawValue, default: 0] += 1 }
+            result[name] = [
+                "version": imported.report.filiusVersion ?? NSNull(),
+                "nodes": imported.report.importedNodeCount,
+                "links": imported.report.importedLinkCount,
+                "documentation": imported.report.importedDocumentationItemCount,
+                "skipped": imported.report.skippedNodeCount,
+                "warnings": imported.report.warnings,
+                "residual": imported.opaqueContent.residualCount,
+                "kinds": kinds,
+            ] as JSON
+        } catch {
+            result[name] = ["error": String(describing: error)] as JSON
+        }
+    }
+    return result
+}
+
 // MARK: - Main
 
+if CommandLine.arguments.count == 4, CommandLine.arguments[1] == "--corpus" {
+    let summary = try readCorpus(root: URL(fileURLWithPath: CommandLine.arguments[2]))
+    let data = try JSONSerialization.data(withJSONObject: summary, options: [.prettyPrinted, .sortedKeys])
+    try (data + Data("\n".utf8)).write(to: URL(fileURLWithPath: CommandLine.arguments[3]))
+    print("corpus: \(summary.count) files")
+    exit(0)
+}
+
 let directory = URL(fileURLWithPath: CommandLine.arguments.dropFirst().first ?? ".")
 let files = try FileManager.default.contentsOfDirectory(at: directory, includingPropertiesForKeys: nil)
     .filter { $0.lastPathComponent.hasSuffix(".scenario.json") }
diff --git a/tools/swift-oracle/core.191 b/tools/swift-oracle/core.191
new file mode 100644
index 0000000..6bcc668
Binary files /dev/null and b/tools/swift-oracle/core.191 differ
diff --git a/tools/swift-oracle/core.7 b/tools/swift-oracle/core.7
new file mode 100644
index 0000000..7d37f31
Binary files /dev/null and b/tools/swift-oracle/core.7 differ
diff --git a/tools/swift-oracle/run.sh b/tools/swift-oracle/run.sh
index 413e0d8..a2df364 100755
--- a/tools/swift-oracle/run.sh
+++ b/tools/swift-oracle/run.sh
@@ -6,5 +6,9 @@ set -eu
 here="$(cd "$(dirname "$0")" && pwd)"
 root="$(cd "$here/../.." && pwd)"
 [ -d "$here/Sources/FiliusCore" ] || "$here/fetch-upstream.sh"
-docker run --rm -v "$root:/work" -w /work/tools/swift-oracle swift:6.1-jammy \
-    sh -c 'swift build -q 2>&1 | grep -v "Sendable\|^ *|\|^ *\`" ; .build/debug/Oracle /work/packages/core/test/scenarios'
+# A failed build must stop here: a stale binary would write stale references.
+docker run --rm -v "$root:/work" -w /work/tools/swift-oracle swift:6.1-jammy sh -c '
+    set -e
+    swift build -q
+    .build/debug/Oracle /work/packages/core/test/scenarios
+    .build/debug/Oracle --corpus /work/corpus /work/corpus/corpus.swift.json'