diff --git a/.gitattributes b/.gitattributes
index 9e2b4945..1c544085 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -5,3 +5,17 @@ launcher-rust/fixtures/** text eol=lf
 launcher-rust/assets/i18n.json text eol=lf
 # Snapshot references are images compared pixel by pixel: never touched as text.
 launcher-rust/snapshots/** binary
+# The runner fixtures: text outputs are LF, every input and output that is bytes is never touched as text.
+launcher-rust/fixtures/runner/**/*.json text eol=lf
+launcher-rust/fixtures/runner/**/*.xml text eol=lf
+launcher-rust/fixtures/runner/**/*.ini text eol=lf
+launcher-rust/fixtures/runner/**/*.bin binary
+launcher-rust/fixtures/runner/**/*.dds binary
+launcher-rust/fixtures/runner/**/*.dxt1 binary
+launcher-rust/fixtures/runner/**/*.dxt5 binary
+launcher-rust/fixtures/runner/**/*.png binary
+launcher-rust/fixtures/runner/**/*.bmp binary
+launcher-rust/fixtures/runner/**/*.WAD binary
+launcher-rust/fixtures/runner/**/*.prx binary
+launcher-rust/fixtures/runner/**/*.sfo binary
+launcher-rust/fixtures/runner/**/*.elf binary
diff --git a/README.md b/README.md
index a5fee56a..31c4390f 100644
--- a/README.md
+++ b/README.md
@@ -481,6 +481,7 @@ cargo test
 The page snapshots under `launcher-rust/snapshots/` are compared pixel by pixel on Windows only.
 `python -m unittest discover -s tests -p "test_launcher_parity_doc.py"` checks that every Python
 launcher test has its row in `docs/specs/2026-10-21-rust-launcher-parity.md`.
+`tools/runner_fixtures.py` generates `launcher-rust/fixtures/runner/`, the inputs and the files the Python runner's modules write over them, for the Rust runner's parity tests.
 
 ### Windows C++ tests (MSYS2 CLANG64)
 
diff --git a/launcher-rust/fixtures/runner/content/expected/full/content-profile.json b/launcher-rust/fixtures/runner/content/expected/full/content-profile.json
new file mode 100644
index 00000000..72c1ed0a
--- /dev/null
+++ b/launcher-rust/fixtures/runner/content/expected/full/content-profile.json
@@ -0,0 +1,13 @@
+{
+  "title_id": "CUSA01623",
+  "sku": "full",
+  "sku_source": "explicit probe setting",
+  "user_params": [
+    13,
+    0,
+    7,
+    4294967295
+  ],
+  "mounted_addons": [],
+  "boot_attr": 0
+}
diff --git a/launcher-rust/fixtures/runner/content/expected/full/content.bin b/launcher-rust/fixtures/runner/content/expected/full/content.bin
new file mode 100644
index 00000000..9750054c
Binary files /dev/null and b/launcher-rust/fixtures/runner/content/expected/full/content.bin differ
diff --git a/launcher-rust/fixtures/runner/content/expected/trial/content-profile.json b/launcher-rust/fixtures/runner/content/expected/trial/content-profile.json
new file mode 100644
index 00000000..f46a8b72
--- /dev/null
+++ b/launcher-rust/fixtures/runner/content/expected/trial/content-profile.json
@@ -0,0 +1,13 @@
+{
+  "title_id": "CUSA01623",
+  "sku": "trial",
+  "sku_source": "explicit probe setting",
+  "user_params": [
+    13,
+    0,
+    7,
+    4294967295
+  ],
+  "mounted_addons": [],
+  "boot_attr": 0
+}
diff --git a/launcher-rust/fixtures/runner/content/expected/trial/content.bin b/launcher-rust/fixtures/runner/content/expected/trial/content.bin
new file mode 100644
index 00000000..e9b967d4
Binary files /dev/null and b/launcher-rust/fixtures/runner/content/expected/trial/content.bin differ
diff --git a/launcher-rust/fixtures/runner/content/input/param.sfo b/launcher-rust/fixtures/runner/content/input/param.sfo
new file mode 100644
index 00000000..34361ccc
Binary files /dev/null and b/launcher-rust/fixtures/runner/content/input/param.sfo differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/alpha.dxt1 b/launcher-rust/fixtures/runner/dxt/expected/alpha.dxt1
new file mode 100644
index 00000000..2447e4d3
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/alpha.dxt1 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/alpha.dxt5 b/launcher-rust/fixtures/runner/dxt/expected/alpha.dxt5
new file mode 100644
index 00000000..34a4810d
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/alpha.dxt5 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/edges.dxt1 b/launcher-rust/fixtures/runner/dxt/expected/edges.dxt1
new file mode 100644
index 00000000..3010c7eb
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/edges.dxt1 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/edges.dxt5 b/launcher-rust/fixtures/runner/dxt/expected/edges.dxt5
new file mode 100644
index 00000000..661bad4e
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/edges.dxt5 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/flat.dxt1 b/launcher-rust/fixtures/runner/dxt/expected/flat.dxt1
new file mode 100644
index 00000000..d6d23e4a
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/flat.dxt1 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/flat.dxt5 b/launcher-rust/fixtures/runner/dxt/expected/flat.dxt5
new file mode 100644
index 00000000..1cf48edc
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/flat.dxt5 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/gradient.dxt1 b/launcher-rust/fixtures/runner/dxt/expected/gradient.dxt1
new file mode 100644
index 00000000..603eef05
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/gradient.dxt1 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/gradient.dxt5 b/launcher-rust/fixtures/runner/dxt/expected/gradient.dxt5
new file mode 100644
index 00000000..3a849cce
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/gradient.dxt5 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/noise.dxt1 b/launcher-rust/fixtures/runner/dxt/expected/noise.dxt1
new file mode 100644
index 00000000..69f9779b
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/noise.dxt1 differ
diff --git a/launcher-rust/fixtures/runner/dxt/expected/noise.dxt5 b/launcher-rust/fixtures/runner/dxt/expected/noise.dxt5
new file mode 100644
index 00000000..fc5f455e
Binary files /dev/null and b/launcher-rust/fixtures/runner/dxt/expected/noise.dxt5 differ
diff --git a/launcher-rust/fixtures/runner/graphics/expected/good/environment.json b/launcher-rust/fixtures/runner/graphics/expected/good/environment.json
new file mode 100644
index 00000000..a2697dee
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/good/environment.json
@@ -0,0 +1,5 @@
+{
+  "SPARTAN_DEFERRED_READBACK": "1",
+  "SPARTAN_STALE_READBACK": "1",
+  "SPARTAN_ASYNC_SHADERS": "1"
+}
diff --git a/launcher-rust/fixtures/runner/graphics/expected/good/graphics_state.json b/launcher-rust/fixtures/runner/graphics/expected/good/graphics_state.json
new file mode 100644
index 00000000..ed8feee9
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/good/graphics_state.json
@@ -0,0 +1,10 @@
+{
+  "last_good": {
+    "render_resolution": "1440p",
+    "engine_fps": "120",
+    "deferred_readback": "1",
+    "stale_readback": "1",
+    "async_shaders": "1"
+  },
+  "attempt": false
+}
\ No newline at end of file
diff --git a/launcher-rust/fixtures/runner/graphics/expected/good/spartanport.ini b/launcher-rust/fixtures/runner/graphics/expected/good/spartanport.ini
new file mode 100644
index 00000000..1350879c
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/good/spartanport.ini
@@ -0,0 +1,2 @@
+render_resolution=1440p
+engine_fps=120
diff --git a/launcher-rust/fixtures/runner/graphics/expected/reverted/environment.json b/launcher-rust/fixtures/runner/graphics/expected/reverted/environment.json
new file mode 100644
index 00000000..a2697dee
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/reverted/environment.json
@@ -0,0 +1,5 @@
+{
+  "SPARTAN_DEFERRED_READBACK": "1",
+  "SPARTAN_STALE_READBACK": "1",
+  "SPARTAN_ASYNC_SHADERS": "1"
+}
diff --git a/launcher-rust/fixtures/runner/graphics/expected/reverted/graphics_state.json b/launcher-rust/fixtures/runner/graphics/expected/reverted/graphics_state.json
new file mode 100644
index 00000000..ed8feee9
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/reverted/graphics_state.json
@@ -0,0 +1,10 @@
+{
+  "last_good": {
+    "render_resolution": "1440p",
+    "engine_fps": "120",
+    "deferred_readback": "1",
+    "stale_readback": "1",
+    "async_shaders": "1"
+  },
+  "attempt": false
+}
\ No newline at end of file
diff --git a/launcher-rust/fixtures/runner/graphics/expected/reverted/spartanport.ini b/launcher-rust/fixtures/runner/graphics/expected/reverted/spartanport.ini
new file mode 100644
index 00000000..8681e6b1
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/reverted/spartanport.ini
@@ -0,0 +1,6 @@
+render_resolution=1440p
+engine_fps=120
+restart_unconfirmed=0
+deferred_readback=1
+stale_readback=1
+async_shaders=1
diff --git a/launcher-rust/fixtures/runner/graphics/expected/tried/environment.json b/launcher-rust/fixtures/runner/graphics/expected/tried/environment.json
new file mode 100644
index 00000000..a2697dee
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/tried/environment.json
@@ -0,0 +1,5 @@
+{
+  "SPARTAN_DEFERRED_READBACK": "1",
+  "SPARTAN_STALE_READBACK": "1",
+  "SPARTAN_ASYNC_SHADERS": "1"
+}
diff --git a/launcher-rust/fixtures/runner/graphics/expected/tried/graphics_state.json b/launcher-rust/fixtures/runner/graphics/expected/tried/graphics_state.json
new file mode 100644
index 00000000..4d329057
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/tried/graphics_state.json
@@ -0,0 +1,10 @@
+{
+  "last_good": {
+    "render_resolution": "1440p",
+    "engine_fps": "120",
+    "deferred_readback": "1",
+    "stale_readback": "1",
+    "async_shaders": "1"
+  },
+  "attempt": true
+}
\ No newline at end of file
diff --git a/launcher-rust/fixtures/runner/graphics/expected/tried/spartanport.ini b/launcher-rust/fixtures/runner/graphics/expected/tried/spartanport.ini
new file mode 100644
index 00000000..b23c9fbd
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/expected/tried/spartanport.ini
@@ -0,0 +1,3 @@
+render_resolution=4K
+engine_fps=240
+restart_unconfirmed=1
diff --git a/launcher-rust/fixtures/runner/graphics/input/edit.json b/launcher-rust/fixtures/runner/graphics/input/edit.json
new file mode 100644
index 00000000..b0ca0d4c
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/input/edit.json
@@ -0,0 +1,5 @@
+{
+  "render_resolution": "4K",
+  "engine_fps": "240",
+  "restart_unconfirmed": "1"
+}
diff --git a/launcher-rust/fixtures/runner/graphics/input/graphics_state.json b/launcher-rust/fixtures/runner/graphics/input/graphics_state.json
new file mode 100644
index 00000000..0967ef42
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/input/graphics_state.json
@@ -0,0 +1 @@
+{}
diff --git a/launcher-rust/fixtures/runner/graphics/input/spartanport.ini b/launcher-rust/fixtures/runner/graphics/input/spartanport.ini
new file mode 100644
index 00000000..1350879c
--- /dev/null
+++ b/launcher-rust/fixtures/runner/graphics/input/spartanport.ini
@@ -0,0 +1,2 @@
+render_resolution=1440p
+engine_fps=120
diff --git a/launcher-rust/fixtures/runner/icon/expected/window_icon.bmp b/launcher-rust/fixtures/runner/icon/expected/window_icon.bmp
new file mode 100644
index 00000000..9349350d
Binary files /dev/null and b/launcher-rust/fixtures/runner/icon/expected/window_icon.bmp differ
diff --git a/launcher-rust/fixtures/runner/isa/expected/isa-rewrite.bin b/launcher-rust/fixtures/runner/isa/expected/isa-rewrite.bin
new file mode 100644
index 00000000..8edb6d5f
Binary files /dev/null and b/launcher-rust/fixtures/runner/isa/expected/isa-rewrite.bin differ
diff --git a/launcher-rust/fixtures/runner/isa/expected/sites.json b/launcher-rust/fixtures/runner/isa/expected/sites.json
new file mode 100644
index 00000000..62d3e890
--- /dev/null
+++ b/launcher-rust/fixtures/runner/isa/expected/sites.json
@@ -0,0 +1,122 @@
+[
+  {
+    "offset": 0,
+    "length": 5,
+    "kind": "BLSR",
+    "width": 32,
+    "mode": "JMP",
+    "registers": {
+      "dst": 1,
+      "src1": 1,
+      "src2": 255,
+      "base": 255,
+      "index": 255
+    },
+    "mem_slot": 0,
+    "scale": 0,
+    "mem_flags": 0,
+    "disp": 0,
+    "original": "c4e270f3c9",
+    "relocated": ""
+  },
+  {
+    "offset": 5,
+    "length": 4,
+    "kind": "MOVBE_STORE",
+    "width": 32,
+    "mode": "JMP_RELOCATE",
+    "registers": {
+      "dst": 255,
+      "src1": 1,
+      "src2": 255,
+      "base": 0,
+      "index": 255
+    },
+    "mem_slot": 1,
+    "scale": 1,
+    "mem_flags": 0,
+    "disp": 0,
+    "original": "0f38f108",
+    "relocated": "90"
+  },
+  {
+    "offset": 10,
+    "length": 9,
+    "kind": "BEXTR",
+    "width": 32,
+    "mode": "JMP",
+    "registers": {
+      "dst": 0,
+      "src1": 255,
+      "src2": 1,
+      "base": 255,
+      "index": 255
+    },
+    "mem_slot": 2,
+    "scale": 1,
+    "mem_flags": 1,
+    "disp": 31,
+    "original": "c4e270f7050c000000",
+    "relocated": ""
+  },
+  {
+    "offset": 19,
+    "length": 5,
+    "kind": "LZCNT",
+    "width": 16,
+    "mode": "JMP",
+    "registers": {
+      "dst": 0,
+      "src1": 1,
+      "src2": 255,
+      "base": 255,
+      "index": 255
+    },
+    "mem_slot": 0,
+    "scale": 0,
+    "mem_flags": 0,
+    "disp": 0,
+    "original": "66f30fbdc1",
+    "relocated": ""
+  },
+  {
+    "offset": 24,
+    "length": 5,
+    "kind": "TZCNT",
+    "width": 64,
+    "mode": "JMP",
+    "registers": {
+      "dst": 0,
+      "src1": 1,
+      "src2": 255,
+      "base": 255,
+      "index": 255
+    },
+    "mem_slot": 0,
+    "scale": 0,
+    "mem_flags": 0,
+    "disp": 0,
+    "original": "f3480fbcc1",
+    "relocated": ""
+  },
+  {
+    "offset": 29,
+    "length": 4,
+    "kind": "MOVBE_STORE",
+    "width": 32,
+    "mode": "INT3",
+    "registers": {
+      "dst": 255,
+      "src1": 1,
+      "src2": 255,
+      "base": 0,
+      "index": 255
+    },
+    "mem_slot": 1,
+    "scale": 1,
+    "mem_flags": 0,
+    "disp": 0,
+    "original": "0f38f108",
+    "relocated": ""
+  }
+]
diff --git a/launcher-rust/fixtures/runner/isa/input/boot-linked.bin b/launcher-rust/fixtures/runner/isa/input/boot-linked.bin
new file mode 100644
index 00000000..4d2b8da2
Binary files /dev/null and b/launcher-rust/fixtures/runner/isa/input/boot-linked.bin differ
diff --git a/launcher-rust/fixtures/runner/link/expected/boot-libc.bin b/launcher-rust/fixtures/runner/link/expected/boot-libc.bin
new file mode 100644
index 00000000..22e7fa6f
Binary files /dev/null and b/launcher-rust/fixtures/runner/link/expected/boot-libc.bin differ
diff --git a/launcher-rust/fixtures/runner/link/expected/boot-linked.bin b/launcher-rust/fixtures/runner/link/expected/boot-linked.bin
new file mode 100644
index 00000000..32752dbc
Binary files /dev/null and b/launcher-rust/fixtures/runner/link/expected/boot-linked.bin differ
diff --git a/launcher-rust/fixtures/runner/link/expected/libc-link.json b/launcher-rust/fixtures/runner/link/expected/libc-link.json
new file mode 100644
index 00000000..b55954ee
--- /dev/null
+++ b/launcher-rust/fixtures/runner/link/expected/libc-link.json
@@ -0,0 +1,37 @@
+{
+  "base": "0x10000",
+  "size": 4096,
+  "sha256": "16bcdb5c0a28f581da21dc76c9e73ed1e8ec35398b85be38352691f4ff4cba33",
+  "init": "0x10010",
+  "bindings": 1,
+  "tls_module_id": 2,
+  "fs_loads_patched": 2,
+  "main_tls": {
+    "vaddr": 3072,
+    "filesz": 16,
+    "memsz": 48,
+    "align": 16
+  },
+  "tls_relocations": 1,
+  "tls_template_bytes": 16,
+  "tls_memory_bytes": 48,
+  "imports": [
+    "bzQExy189ZI#q#q",
+    "AAAAAAAAAAA#q#q",
+    "DDDDDDDDDDD#q#q"
+  ],
+  "relocation_counts": {
+    "8": 1,
+    "16": 1,
+    "1": 1,
+    "6": 1,
+    "7": 1
+  },
+  "symbol_bindings": [
+    {
+      "import_name": "bzQExy189ZI#q#q",
+      "address": "0x10010",
+      "kind": 1
+    }
+  ]
+}
diff --git a/launcher-rust/fixtures/runner/link/expected/link.json b/launcher-rust/fixtures/runner/link/expected/link.json
new file mode 100644
index 00000000..ac24c23a
--- /dev/null
+++ b/launcher-rust/fixtures/runner/link/expected/link.json
@@ -0,0 +1,43 @@
+{
+  "modules": [
+    {
+      "file": "libc.prx",
+      "base": "0x10000",
+      "size": 4096,
+      "init": "0x10010",
+      "tls_address": "0x10500",
+      "tls_memsz": 48,
+      "tls_filesz": 16,
+      "tls_module": 2,
+      "tls_relocations": 1,
+      "exports": 3,
+      "sha256": "16bcdb5c0a28f581da21dc76c9e73ed1e8ec35398b85be38352691f4ff4cba33"
+    },
+    {
+      "file": "libSceFios2.prx",
+      "base": "0x20000",
+      "size": 2048,
+      "init": "0x20000",
+      "tls_address": "0x0",
+      "tls_memsz": 0,
+      "tls_filesz": 0,
+      "tls_module": 0,
+      "tls_relocations": 0,
+      "exports": 1,
+      "sha256": "a7ae78118c4fcb8dd27129c2b8059fbcf2e0d685b4ad8b40038fa43f4d93e4f2"
+    }
+  ],
+  "bindings": 2,
+  "imports": 4,
+  "fs_loads_patched": 4,
+  "main_tls": {
+    "vaddr": 3072,
+    "filesz": 16,
+    "memsz": 48,
+    "align": 16
+  },
+  "unresolved_imports": [
+    "AAAAAAAAAAA#libc",
+    "DDDDDDDDDDD#libc"
+  ]
+}
diff --git a/launcher-rust/fixtures/runner/link/input/boot.bin b/launcher-rust/fixtures/runner/link/input/boot.bin
new file mode 100644
index 00000000..52118313
Binary files /dev/null and b/launcher-rust/fixtures/runner/link/input/boot.bin differ
diff --git a/launcher-rust/fixtures/runner/link/input/eboot.bin b/launcher-rust/fixtures/runner/link/input/eboot.bin
new file mode 100644
index 00000000..e1c1d5ed
Binary files /dev/null and b/launcher-rust/fixtures/runner/link/input/eboot.bin differ
diff --git a/launcher-rust/fixtures/runner/link/input/sce_module/libSceFios2.prx b/launcher-rust/fixtures/runner/link/input/sce_module/libSceFios2.prx
new file mode 100644
index 00000000..c7cafc1e
Binary files /dev/null and b/launcher-rust/fixtures/runner/link/input/sce_module/libSceFios2.prx differ
diff --git a/launcher-rust/fixtures/runner/link/input/sce_module/libc.prx b/launcher-rust/fixtures/runner/link/input/sce_module/libc.prx
new file mode 100644
index 00000000..d1ab1bb0
Binary files /dev/null and b/launcher-rust/fixtures/runner/link/input/sce_module/libc.prx differ
diff --git a/launcher-rust/fixtures/runner/patches/expected/patch_status.json b/launcher-rust/fixtures/runner/patches/expected/patch_status.json
new file mode 100644
index 00000000..f1652f37
--- /dev/null
+++ b/launcher-rust/fixtures/runner/patches/expected/patch_status.json
@@ -0,0 +1 @@
+{"sha256": "ffed585c6a2b513546eba7f283c45ad27382a8e31cf54fe03b4e1c0ca63195d5", "applied": ["Found", "Call", "Data"], "skipped": {"Missing": "signature not found"}}
\ No newline at end of file
diff --git a/launcher-rust/fixtures/runner/patches/expected/patches-merged.xml b/launcher-rust/fixtures/runner/patches/expected/patches-merged.xml
new file mode 100644
index 00000000..0366f3d0
--- /dev/null
+++ b/launcher-rust/fixtures/runner/patches/expected/patches-merged.xml
@@ -0,0 +1,44 @@
+<?xml version='1.0' encoding='utf-8'?>
+<Patch>
+  <TitleID>
+    <ID>CUSA01623</ID>
+  </TitleID>
+  <Metadata Name="Found" AppVer="01.02">
+    <PatchList>
+      <Line Type="bytes" Address="0x401004" Value="9090" Pattern="11 22 ?? 44 55 66" At="1" />
+    </PatchList>
+  </Metadata>
+  <Metadata Name="Call" AppVer="01.02">
+    <PatchList>
+      <Line Type="bytes" Address="0x401010" Value="e8{rel:there:0}" Pattern="aa bb cc dd ee" At="0" />
+    </PatchList>
+    <Target Name="there" Address="0x401100" Pattern="e9 ?? ?? ?? ?? 77 88" At="1" Ref="1" />
+  </Metadata>
+  <Metadata Name="Missing" AppVer="01.02">
+    <PatchList>
+      <Line Type="bytes" Address="0x401004" Value="9090" Pattern="11 22 ?? 44 55 66" At="1" />
+      <Line Type="bytes" Address="0x401020" Value="90" Pattern="de ad be ef" At="0" />
+    </PatchList>
+  </Metadata>
+  <Metadata Name="Data" AppVer="01.02">
+    <PatchList>
+      <Line Type="bytes32" Address="0x402000" Target="variable" Value="0x2" />
+    </PatchList>
+    <Target Name="variable" Address="0x402000" Pattern="44 89 35 ?? ?? ?? ?? c6" At="3" Ref="1" />
+  </Metadata>
+  <Metadata Name="Resolution Patch - 3440x1440" Note="Requires setting DMEM to 4608 MB or more." AppVer="01.02" AppElf="eboot.bin" isEnabled="false">
+    <PatchList>
+      <Line Type="bytes" Address="0x00401000" Value="9090" />
+    </PatchList>
+  </Metadata>
+  <Metadata Name="Resolution Patch - 2560x1080" AppVer="01.02" AppElf="eboot.bin" isEnabled="false">
+    <PatchList>
+      <Line Type="bytes" Address="0x00401000" Value="9090" />
+    </PatchList>
+  </Metadata>
+  <Metadata Name="Skip Any Video With X Button" Note="replaced by the mod" AppVer="01.02" AppElf="eboot.bin" isEnabled="true">
+    <PatchList>
+      <Line Type="bytes" Address="0x00401002" Value="90" />
+    </PatchList>
+  </Metadata>
+</Patch>
\ No newline at end of file
diff --git a/launcher-rust/fixtures/runner/patches/expected/patches.bin b/launcher-rust/fixtures/runner/patches/expected/patches.bin
new file mode 100644
index 00000000..bdf3d8d6
Binary files /dev/null and b/launcher-rust/fixtures/runner/patches/expected/patches.bin differ
diff --git a/launcher-rust/fixtures/runner/patches/input/eboot.bin b/launcher-rust/fixtures/runner/patches/input/eboot.bin
new file mode 100644
index 00000000..9895ccd9
--- /dev/null
+++ b/launcher-rust/fixtures/runner/patches/input/eboot.bin
@@ -0,0 +1 @@
+synthetic eboot.bin of the patches case
diff --git a/launcher-rust/fixtures/runner/patches/input/eboot.elf b/launcher-rust/fixtures/runner/patches/input/eboot.elf
new file mode 100644
index 00000000..36bb9e2f
Binary files /dev/null and b/launcher-rust/fixtures/runner/patches/input/eboot.elf differ
diff --git a/launcher-rust/fixtures/runner/patches/input/mod.xml b/launcher-rust/fixtures/runner/patches/input/mod.xml
new file mode 100644
index 00000000..087b4410
--- /dev/null
+++ b/launcher-rust/fixtures/runner/patches/input/mod.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0"?>
+<Patch>
+  <TitleID><ID>CUSA01623</ID></TitleID>
+  <Metadata Name="Resolution Patch - 3440x1440" Note="Requires setting DMEM to 4608 MB or more." AppVer="01.02" AppElf="eboot.bin" isEnabled="false">
+    <PatchList><Line Type="bytes" Address="0x00401000" Value="9090"/></PatchList>
+  </Metadata>
+  <Metadata Name="Resolution Patch - 2560x1080" AppVer="01.02" AppElf="eboot.bin" isEnabled="false">
+    <PatchList><Line Type="bytes" Address="0x00401000" Value="9090"/></PatchList>
+  </Metadata>
+  <Metadata Name="Skip Any Video With X Button" Note="replaced by the mod" AppVer="01.02" AppElf="eboot.bin" isEnabled="true">
+    <PatchList><Line Type="bytes" Address="0x00401002" Value="90"/></PatchList>
+  </Metadata>
+</Patch>
\ No newline at end of file
diff --git a/launcher-rust/fixtures/runner/patches/input/param.sfo b/launcher-rust/fixtures/runner/patches/input/param.sfo
new file mode 100644
index 00000000..331ffa86
Binary files /dev/null and b/launcher-rust/fixtures/runner/patches/input/param.sfo differ
diff --git a/launcher-rust/fixtures/runner/patches/input/patches.xml b/launcher-rust/fixtures/runner/patches/input/patches.xml
new file mode 100644
index 00000000..1d67a4be
--- /dev/null
+++ b/launcher-rust/fixtures/runner/patches/input/patches.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<Patch>
+  <TitleID><ID>CUSA01623</ID></TitleID>
+  <Metadata Name="Found" AppVer="01.02">
+    <PatchList><Line Type="bytes" Address="0x401004" Value="9090" Pattern="11 22 ?? 44 55 66" At="1"/></PatchList>
+  </Metadata>
+  <Metadata Name="Call" AppVer="01.02">
+    <PatchList><Line Type="bytes" Address="0x401010" Value="e8{rel:there:0}" Pattern="aa bb cc dd ee" At="0"/></PatchList>
+    <Target Name="there" Address="0x401100" Pattern="e9 ?? ?? ?? ?? 77 88" At="1" Ref="1"/>
+  </Metadata>
+  <Metadata Name="Missing" AppVer="01.02">
+    <PatchList>
+      <Line Type="bytes" Address="0x401004" Value="9090" Pattern="11 22 ?? 44 55 66" At="1"/>
+      <Line Type="bytes" Address="0x401020" Value="90" Pattern="de ad be ef" At="0"/>
+    </PatchList>
+  </Metadata>
+  <Metadata Name="Data" AppVer="01.02">
+    <PatchList><Line Type="bytes32" Address="0x402000" Target="variable" Value="0x2"/></PatchList>
+    <Target Name="variable" Address="0x402000" Pattern="44 89 35 ?? ?? ?? ?? c6" At="3" Ref="1"/>
+  </Metadata>
+</Patch>
\ No newline at end of file
diff --git a/launcher-rust/fixtures/runner/prepare/expected/analysis.json b/launcher-rust/fixtures/runner/prepare/expected/analysis.json
new file mode 100644
index 00000000..4d56ea28
--- /dev/null
+++ b/launcher-rust/fixtures/runner/prepare/expected/analysis.json
@@ -0,0 +1,142 @@
+{
+  "source_sha256": "138b11e351ce338943e47f76805cfba5380996355ea098c97be4fd586002d96c",
+  "source_bytes": 5400,
+  "sfo": {
+    "APP_VER": "01.02",
+    "CONTENT_ID": "EP9000-CUSA01623_00-GOW3REMASTERED00",
+    "TITLE": "ゴッド・オブ・ウォーIII リマスタード",
+    "TITLE_ID": "CUSA01623",
+    "USER_DEFINED_PARAM_1": 13,
+    "USER_DEFINED_PARAM_2": 0,
+    "USER_DEFINED_PARAM_3": 7,
+    "USER_DEFINED_PARAM_4": 4294967295
+  },
+  "entry": "0x10",
+  "image_bytes": 4096,
+  "program_headers": [
+    {
+      "type": 1,
+      "flags": 5,
+      "offset": 4096,
+      "vaddr": 0,
+      "paddr": 0,
+      "filesz": 2048,
+      "memsz": 2048,
+      "align": 16384
+    },
+    {
+      "type": 1,
+      "flags": 6,
+      "offset": 6144,
+      "vaddr": 2048,
+      "paddr": 2048,
+      "filesz": 2048,
+      "memsz": 2048,
+      "align": 16384
+    },
+    {
+      "type": 2,
+      "flags": 4,
+      "offset": 8192,
+      "vaddr": 0,
+      "paddr": 0,
+      "filesz": 192,
+      "memsz": 0,
+      "align": 8
+    },
+    {
+      "type": 1627389952,
+      "flags": 4,
+      "offset": 8448,
+      "vaddr": 0,
+      "paddr": 0,
+      "filesz": 344,
+      "memsz": 0,
+      "align": 8
+    },
+    {
+      "type": 1627389953,
+      "flags": 4,
+      "offset": 8960,
+      "vaddr": 128,
+      "paddr": 128,
+      "filesz": 0,
+      "memsz": 64,
+      "align": 8
+    },
+    {
+      "type": 7,
+      "flags": 4,
+      "offset": 7168,
+      "vaddr": 3072,
+      "paddr": 3072,
+      "filesz": 16,
+      "memsz": 48,
+      "align": 16
+    }
+  ],
+  "self_segments": [
+    {
+      "flags": "0x800",
+      "offset": 768,
+      "size": 2048
+    },
+    {
+      "flags": "0x100800",
+      "offset": 2816,
+      "size": 2048
+    },
+    {
+      "flags": "0x200800",
+      "offset": 4864,
+      "size": 192
+    },
+    {
+      "flags": "0x300800",
+      "offset": 5056,
+      "size": 344
+    }
+  ],
+  "unavailable_metadata_headers": [],
+  "needed": [
+    "libc.prx"
+  ],
+  "relocation_counts": {
+    "8": 1,
+    "6": 2,
+    "1": 1,
+    "7": 2
+  },
+  "import_count": 2,
+  "imports": [
+    "bzQExy189ZI#q#q",
+    "AAAAAAAAAAA#q#q"
+  ],
+  "import_name_hints": {
+    "bzQExy189ZI#q#q": "_init_env"
+  },
+  "libc_evidence": {
+    "sha256": "16bcdb5c0a28f581da21dc76c9e73ed1e8ec35398b85be38352691f4ff4cba33",
+    "init_env_is_ret": true,
+    "symbol": "bzQExy189ZI#C#A",
+    "address": "0x10",
+    "size": 1,
+    "bytes": "c3",
+    "ios_base_init": {
+      "symbol": "sqWytnhYdEg#C#A",
+      "address": "0x20",
+      "size": 3,
+      "code_sha256": "251447ee91a9067dcd6ab96703133f617565974cd6c4819021760c4688c91abf",
+      "name": "_ZNSt8ios_base4InitC1Ev"
+    }
+  },
+  "bundled_modules": [
+    "libc.prx"
+  ],
+  "resources": {
+    "PART1.WAD": 1,
+    "sound": 1
+  },
+  "resource_bytes": 132,
+  "status": "Prepared only; execution and Vulkan are tested separately."
+}
diff --git a/launcher-rust/fixtures/runner/prepare/expected/boot.bin b/launcher-rust/fixtures/runner/prepare/expected/boot.bin
new file mode 100644
index 00000000..2f5242ca
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/expected/boot.bin differ
diff --git a/launcher-rust/fixtures/runner/prepare/expected/eboot.elf b/launcher-rust/fixtures/runner/prepare/expected/eboot.elf
new file mode 100644
index 00000000..4e828a14
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/expected/eboot.elf differ
diff --git a/launcher-rust/fixtures/runner/prepare/expected/entry.bin b/launcher-rust/fixtures/runner/prepare/expected/entry.bin
new file mode 100644
index 00000000..7a13f328
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/expected/entry.bin differ
diff --git a/launcher-rust/fixtures/runner/prepare/input/dvdroot_ps4/PART1.WAD b/launcher-rust/fixtures/runner/prepare/input/dvdroot_ps4/PART1.WAD
new file mode 100644
index 00000000..edf1f4a8
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/input/dvdroot_ps4/PART1.WAD differ
diff --git a/launcher-rust/fixtures/runner/prepare/input/dvdroot_ps4/sound/music.bin b/launcher-rust/fixtures/runner/prepare/input/dvdroot_ps4/sound/music.bin
new file mode 100644
index 00000000..eeb57607
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/input/dvdroot_ps4/sound/music.bin differ
diff --git a/launcher-rust/fixtures/runner/prepare/input/eboot.bin b/launcher-rust/fixtures/runner/prepare/input/eboot.bin
new file mode 100644
index 00000000..e1c1d5ed
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/input/eboot.bin differ
diff --git a/launcher-rust/fixtures/runner/prepare/input/sce_module/libc.prx b/launcher-rust/fixtures/runner/prepare/input/sce_module/libc.prx
new file mode 100644
index 00000000..d1ab1bb0
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/input/sce_module/libc.prx differ
diff --git a/launcher-rust/fixtures/runner/prepare/input/sce_sys/param.sfo b/launcher-rust/fixtures/runner/prepare/input/sce_sys/param.sfo
new file mode 100644
index 00000000..d6c3bc74
Binary files /dev/null and b/launcher-rust/fixtures/runner/prepare/input/sce_sys/param.sfo differ
diff --git a/tests/test_runner_generators.py b/tests/test_runner_generators.py
new file mode 100644
index 00000000..23ff3100
--- /dev/null
+++ b/tests/test_runner_generators.py
@@ -0,0 +1,58 @@
+"""The Rust runner's parity fixtures: what tools/runner_fixtures.py wrote from the Python modules."""
+import unittest
+
+from paths import ROOT
+
+FIXTURES = ROOT / 'launcher-rust/fixtures/runner'
+DXT_NAMES = ('gradient', 'edges', 'alpha', 'noise', 'flat')
+
+# case -> (input files, expected files), relative to the case folder's input/ and expected/.
+CASES = {
+    'prepare': (['eboot.bin', 'sce_module/libc.prx', 'sce_sys/param.sfo', 'dvdroot_ps4/PART1.WAD'],
+                ['boot.bin', 'eboot.elf', 'entry.bin', 'analysis.json']),
+    'link': (['boot.bin', 'eboot.bin', 'sce_module/libc.prx', 'sce_module/libSceFios2.prx'],
+             ['boot-libc.bin', 'libc-link.json', 'boot-linked.bin', 'link.json']),
+    'isa': (['boot-linked.bin'], ['isa-rewrite.bin', 'sites.json']),
+    'content': (['param.sfo'], ['full/content.bin', 'full/content-profile.json',
+                                'trial/content.bin', 'trial/content-profile.json']),
+    'patches': (['eboot.elf', 'eboot.bin', 'param.sfo', 'patches.xml', 'mod.xml'],
+                ['patches-merged.xml', 'patches.bin', 'patch_status.json']),
+    'graphics': (['spartanport.ini', 'graphics_state.json', 'edit.json'],
+                 [f'{state}/{name}' for state in ('good', 'tried', 'reverted')
+                  for name in ('spartanport.ini', 'graphics_state.json', 'environment.json')]),
+    'dxt': ([f'{name}.png' for name in DXT_NAMES],
+            [f'{name}.{fmt}' for name in DXT_NAMES for fmt in ('dxt1', 'dxt5')]),
+    'icon': ([], ['window_icon.bmp']),
+}
+
+
+class RunnerFixtures(unittest.TestCase):
+    def test_every_case_has_its_files(self):
+        for case, (inputs, expected) in CASES.items():
+            for folder, names in (('input', inputs), ('expected', expected)):
+                for name in names:
+                    path = FIXTURES / case / folder / name
+                    self.assertTrue(path.is_file(), f'{case}/{folder}/{name}')
+
+    def test_dxt_strips_are_whole_blocks(self):
+        for name in DXT_NAMES:
+            # 64 x 64 pixels are 16 x 16 blocks of 8 (DXT1) and 16 (DXT5) bytes.
+            dxt1 = (FIXTURES / 'dxt/expected' / f'{name}.dxt1').read_bytes()
+            dxt5 = (FIXTURES / 'dxt/expected' / f'{name}.dxt5').read_bytes()
+            self.assertEqual((len(dxt1) % 8, len(dxt1)), (0, 16 * 16 * 8), name)
+            self.assertEqual((len(dxt5) % 16, len(dxt5)), (0, 16 * 16 * 16), name)
+
+    def test_content_profile_is_twenty_eight_bytes(self):
+        for sku in ('full', 'trial'):
+            data = (FIXTURES / 'content/expected' / sku / 'content.bin').read_bytes()
+            self.assertEqual(len(data), 28, sku)
+            self.assertEqual(data[:8], b'G3CONT01', sku)
+
+    def test_isa_table_of_the_c_loader_fixture_is_reproduced(self):
+        # The isa input is a G3PROBE5 image holding isa_fixture.bin's code: its table is that file.
+        table = (FIXTURES / 'isa/expected/isa-rewrite.bin').read_bytes()
+        self.assertEqual(table, (ROOT / 'tests/data/isa_fixture.bin').read_bytes())
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/tools/runner_fixtures.py b/tools/runner_fixtures.py
new file mode 100644
index 00000000..61a60734
--- /dev/null
+++ b/tools/runner_fixtures.py
@@ -0,0 +1,492 @@
+"""One-off: runs the Python runner's own modules (scripts/*.py) over synthetic inputs and stores what they
+write in launcher-rust/fixtures/runner/<case>/{input,expected}/, for the Rust runner's byte-for-byte parity tests.
+
+Run from anywhere: python tools/runner_fixtures.py   (needs Pillow and iced_x86)
+
+Every case folder holds input/ (what the module reads) and expected/ (what it wrote). A game folder keeps its
+own layout inside input/ (eboot.bin, sce_module/*.prx, sce_sys/param.sfo, dvdroot_ps4/...), so a test can
+copy input/ as it is. Text outputs are written with LF; no expected file holds the temporary folder (the
+generator stops when one does).
+
+  prepare   input: a synthetic eboot.bin SELF (two PT_LOAD, dynamic, library blob with imports and the four
+            relocation kinds, TLS) with sce_module/libc.prx (its _init_env is RET), sce_sys/param.sfo and a
+            dvdroot_ps4 folder. expected: boot.bin, eboot.elf, entry.bin, analysis.json (scripts/prepare.py).
+  link      input: the same eboot.bin, libc.prx and libSceFios2.prx, and boot.bin from tests/test_probe.package
+            (a freshly prepared G3PROBE2 image with the eboot's imports). expected: boot-libc.bin and
+            libc-link.json (link_libc.py), boot-linked.bin and link.json (link_modules.py).
+  isa       input: boot-linked.bin, a G3PROBE5 image (tests/test_isa_rewrite.boot_linked) whose one executable
+            segment is isa_rewrite.fixture_code(). expected: isa-rewrite.bin (equal to tests/data/isa_fixture.bin)
+            and sites.json, one entry per site: offset, length, kind and mode names, width, registers
+            (dst, src1, src2, base, index; 255 is none), mem_slot, scale, mem_flags, disp, original and
+            relocated bytes as hex.
+  content   input: param.sfo with the four user-defined parameters. expected: full/ and trial/ with
+            content.bin and content-profile.json (content_profile.py).
+  patches   input: eboot.elf holding the signatures of tests/test_patches.SignatureTests in its one PT_LOAD,
+            eboot.bin and param.sfo (CUSA01623, 01.02: the game folder patches.py looks the profile up in),
+            patches.xml (SignatureTests.XML with a TitleID so the mod file merges in) and mod.xml
+            (ModPatchTests.MOD). patches.py main() runs with --mod-patches mod.xml --extra "Found;Call;Missing;Data"
+            and SPARTAN_PATCHES_ONLY=1. expected: patches-merged.xml, patches.bin, patch_status.json (Missing is
+            skipped: its second signature is absent).
+  graphics  input: spartanport.ini, graphics_state.json ({}) and edit.json, the keys written between the
+            launches. graphics_options.prepare runs three times, as in
+            test_unconfirmed_restart_is_tried_once_then_reverted; expected/<good|tried|reverted>/ holds the ini,
+            the state file and environment.json after each launch.
+  dxt       input: gradient, edges, alpha, noise and flat, 64 x 64 RGBA PNGs (noise from a fixed seed).
+            expected: <name>.dxt1 and <name>.dxt5, the 4-row strips of glyphs.encode_region concatenated with
+            each DDS header (128 bytes) stripped (RGB for DXT1, RGBA for DXT5).
+  icon      expected: window_icon.bmp, launcher/spartanport.png as run.py makes it (RGBA, 64 x 64 LANCZOS, BMP)."""
+import contextlib
+import io
+import json
+import os
+import random
+import shutil
+import struct
+import sys
+import tempfile
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parent.parent
+FIXTURES = ROOT / 'launcher-rust' / 'fixtures' / 'runner'
+WORK = Path(tempfile.mkdtemp(prefix='runner_fixtures_'))
+
+sys.path.insert(0, str(ROOT / 'tests'))
+sys.path.insert(0, str(ROOT / 'scripts'))
+import content_profile  # noqa: E402
+import glyphs  # noqa: E402
+import graphics_options  # noqa: E402
+import isa_rewrite  # noqa: E402
+import link_libc  # noqa: E402
+import link_modules  # noqa: E402
+import patches  # noqa: E402
+import prepare as prepare_module  # noqa: E402
+from PIL import Image  # noqa: E402
+from test_isa_rewrite import boot_linked  # noqa: E402
+from test_patches import ModPatchTests, SignatureTests  # noqa: E402
+from test_probe import package  # noqa: E402
+
+FS_LOAD = bytes.fromhex('64488b042500000000')  # mov rax, fs:[0]: what the linkers rewrite to GS
+PARAMS = {'USER_DEFINED_PARAM_1': 13, 'USER_DEFINED_PARAM_2': 0, 'USER_DEFINED_PARAM_3': 7,
+          'USER_DEFINED_PARAM_4': 0xffffffff}
+EDIT = {'render_resolution': '4K', 'engine_fps': '240', 'restart_unconfirmed': '1'}
+
+
+# -- Synthetic files ----------------------------------------------------------------------------------------
+
+def sfo_bytes(values):
+    """A param.sfo (PSF 1.1): strings (0x204) and unsigned integers (0x404), keys sorted."""
+    keys, data, entries = b'', b'', []
+    for key, value in sorted(values.items()):
+        if isinstance(value, int):
+            fmt, raw, capacity = 0x404, struct.pack('<I', value), 4
+        else:
+            raw = value.encode('utf-8') + b'\0'
+            fmt, capacity = 0x204, (len(raw) + 3) // 4 * 4
+        entries.append((len(keys), fmt, len(raw), capacity, len(data)))
+        keys += key.encode() + b'\0'
+        data += raw.ljust(capacity, b'\0')
+    key_table = 20 + 16 * len(entries)
+    data_table = (key_table + len(keys) + 3) // 4 * 4
+    head = struct.pack('<4sIIII', b'\0PSF', 0x101, key_table, data_table, len(entries))
+    return (head + b''.join(struct.pack('<HHIII', *e) for e in entries)
+            + keys.ljust(data_table - key_table, b'\0') + data)
+
+
+class Strings:
+    """A string table: an empty string at offset 0, then each text once."""
+
+    def __init__(self):
+        self.data, self.at = bytearray(b'\0'), {}
+
+    def add(self, text):
+        if text not in self.at:
+            self.at[text] = len(self.data)
+            self.data += text.encode() + b'\0'
+        return self.at[text]
+
+
+def symbol(strings, name, info, section=0, value=0, size=0):
+    return struct.pack('<IBBHQQ', strings.add(name) if name else 0, info, 0, section, value, size)
+
+
+def relocation(target, kind, sym=0, addend=0):
+    return struct.pack('<QQq', target, (sym << 32) | kind, addend)
+
+
+def identifier(ident, version, name_offset):
+    """A library or module dynamic tag value: id in the top 16 bits, version, name offset."""
+    return (ident << 48) | (version << 32) | name_offset
+
+
+def library_blob(strings, symbols, rela, plt):
+    """The 0x61000000 segment (strings, symbols, relocation tables) and the dynamic tags that locate them."""
+    tags, blob = {}, b''
+    for names, content in ((('str', 0x61000035, 0x61000037), bytes(strings.data)),
+                           (('sym', 0x61000039, 0x6100003f), b''.join(symbols)),
+                           (('rela', 0x61000029, 0x6100002d), b''.join(rela)),
+                           (('plt', 0x6100002f, 0x61000031), b''.join(plt))):
+        tags[names[1]], tags[names[2]] = len(blob), len(content)
+        blob += content.ljust((len(content) + 7) // 8 * 8, b'\0')
+    return blob, [(tag, value) for tag, value in tags.items()]
+
+
+def dynamic_bytes(tags):
+    return b''.join(struct.pack('<QQ', *t) for t in tags + [(0, 0)])
+
+
+def make_self(segments, e_type, entry=0):
+    """A SELF around an ELF with these program headers. A segment is a dict: type, flags, vaddr, memsz, align,
+    data (its file bytes), covered (stored in the SELF; the others are metadata the unpacker reports as
+    unavailable) and, for a segment inside another one's bytes, inside (its index) and at (offset in it)."""
+    cursor = 0x1000
+    for s in segments:
+        if 'inside' in s:
+            s['offset'] = segments[s['inside']]['offset'] + s['at']
+        else:
+            s['offset'] = cursor
+            cursor = (cursor + len(s['data']) + 0xff) // 0x100 * 0x100
+    phdrs = b''.join(struct.pack('<IIQQQQQQ', s['type'], s['flags'], s['offset'], s['vaddr'], s['vaddr'],
+                                 len(s['data']), s['memsz'], s['align']) for s in segments)
+    elf_head = struct.pack('<16sHHIQQQIHHHHHH', b'\x7fELF\x02\x01\x01\x09', e_type, 62, 1, entry, 64, 0, 0,
+                           64, 56, len(segments), 0, 0, 0) + phdrs
+    stored = [(i, s) for i, s in enumerate(segments) if s.get('covered') and s['data']]
+    base = 32 + 32 * len(stored)
+    position = (base + len(elf_head) + 0xff) // 0x100 * 0x100
+    table, payload = b'', b''
+    for i, s in stored:
+        table += struct.pack('<QQQQ', 0x800 | (i << 20), position + len(payload), len(s['data']), len(s['data']))
+        payload += s['data']
+    head = (b'O\x15=\x1d' + bytes(20) + struct.pack('<H', len(stored))).ljust(32, b'\0')
+    return (head + table + elf_head).ljust(position, b'\0') + payload
+
+
+def load(vaddr, flags, data, memsz, **extra):
+    return dict(type=1, flags=flags, vaddr=vaddr, memsz=memsz, align=0x4000, data=data, covered=True, **extra)
+
+
+def code_page(size, pieces):
+    page = bytearray(size)
+    for at, code in pieces:
+        page[at:at + len(code)] = code
+    return bytes(page)
+
+
+def eboot_parts():
+    """(SELF bytes, import names, code): the synthetic eboot of the prepare and link cases. It imports _init_env
+    (a function the libc exports), an unknown function and data object, and defines one symbol of its own."""
+    nid = prepare_module.nid
+    strings = Strings()
+    needed, libc = strings.add('libc.prx'), strings.add('libc')
+    names = [nid('_init_env') + '#q#q', 'AAAAAAAAAAA#q#q']
+    symbols = [symbol(strings, '', 0),
+               symbol(strings, names[0], 0x12),                       # import, function
+               symbol(strings, names[1], 0x11),                       # import, object
+               symbol(strings, 'BBBBBBBBBBB#q#q', 0x12, 1, 0x40, 8),  # defined here
+               symbol(strings, 'CCCCCCCCCCC#q#q', 0x11, 0xfff1, 0x1234)]  # absolute
+    rela = [relocation(0x800, 8, 0, 0x40), relocation(0x808, 6, 3, 0x10), relocation(0x810, 1, 4, 4)]
+    plt = [relocation(0x818, 7, 1), relocation(0x820, 6, 2), relocation(0x828, 7, 1)]
+    blob, tags = library_blob(strings, symbols, rela, plt)
+    tags = [(1, needed), (0x61000013, identifier(42, 1, libc)), (0x6100000d, identifier(42, 1, libc))] + tags
+    code = code_page(0x800, [(0x10, bytes.fromhex('31c0c3')), (0x20, FS_LOAD + b'\x90'), (0x40, FS_LOAD + b'\xc3')])
+    data = bytes(i & 255 for i in range(0x800))
+    segments = [load(0, 5, code, 0x800), load(0x800, 6, data, 0x800),
+                dict(type=2, flags=4, vaddr=0, memsz=0, align=8, data=dynamic_bytes(tags), covered=True),
+                dict(type=0x61000000, flags=4, vaddr=0, memsz=0, align=8, data=blob, covered=True),
+                dict(type=0x61000001, flags=4, vaddr=0x80, memsz=0x40, align=8, data=b''),
+                dict(type=7, flags=4, vaddr=0xc00, memsz=0x30, align=16, data=data[0x400:0x410],
+                     inside=1, at=0x400)]
+    return make_self(segments, 0xfe10, 0x10), names, code
+
+
+def libc_self():
+    """A libc.prx: _init_env is RET, one more function, one object, a TLS template, base-relative, TLS, import
+    and defined-symbol relocations and an init function (dynamic tag 12)."""
+    nid = prepare_module.nid
+    strings = Strings()
+    name = strings.add('libc')
+    symbols = [symbol(strings, '', 3),
+               symbol(strings, nid('_init_env') + '#C#A', 0x12, 1, 0x10, 1),
+               symbol(strings, 'DDDDDDDDDDD#C#A', 0x12),
+               symbol(strings, nid('_ZNSt8ios_base4InitC1Ev') + '#C#A', 0x12, 1, 0x20, 3),
+               symbol(strings, 'EEEEEEEEEEE#C#A', 0x11, 1, 0x600, 8)]
+    rela = [relocation(0x400, 8, 0, 0x10), relocation(0x408, 16), relocation(0x410, 1, 1), relocation(0x418, 6, 2)]
+    plt = [relocation(0x420, 7, 2)]
+    blob, tags = library_blob(strings, symbols, rela, plt)
+    tags = [(12, 0x10), (0x61000013, identifier(2, 1, name)), (0x6100000d, identifier(0, 1, name))] + tags
+    code = code_page(0x800, [(0x10, b'\xc3'), (0x20, bytes.fromhex('31c0c3')), (0x30, FS_LOAD + b'\xc3')])
+    segments = [load(0, 5, code, 0x1000),
+                dict(type=2, flags=4, vaddr=0, memsz=0, align=8, data=dynamic_bytes(tags), covered=True),
+                dict(type=0x61000000, flags=4, vaddr=0, memsz=0, align=8, data=blob, covered=True),
+                dict(type=7, flags=4, vaddr=0x500, memsz=0x30, align=16, data=bytes(range(16)),
+                     inside=0, at=0x500)]
+    return make_self(segments, 0xfe18)
+
+
+def fios_self():
+    """A libSceFios2.prx: one export, a weak undefined module_start, an import served by libc's same-NID export
+    (library libSceLibcInternal), a defined-symbol and a base-relative relocation; no TLS."""
+    strings = Strings()
+    fios, internal = strings.add('libSceFios2'), strings.add('libSceLibcInternal')
+    symbols = [symbol(strings, '', 0),
+               symbol(strings, 'Ov1r5aKFXlE#D#B', 0x12, 1, 0x10, 1),
+               symbol(strings, 'module_start', 0x20),
+               symbol(strings, prepare_module.nid('_init_env') + '#E#F', 0x12)]
+    rela = [relocation(0x200, 8, 0, 0x20), relocation(0x208, 1, 2), relocation(0x210, 7, 3), relocation(0x218, 6, 1)]
+    blob, tags = library_blob(strings, symbols, rela, [])
+    tags = [(0x61000013, identifier(3, 1, fios)), (0x61000013, identifier(4, 1, internal)),
+            (0x6100000d, identifier(1, 1, fios)), (0x6100000d, identifier(5, 1, internal))] + tags
+    code = code_page(0x400, [(0x10, b'\xc3'), (0x30, FS_LOAD + b'\xc3')])
+    segments = [load(0, 5, code, 0x800),
+                dict(type=2, flags=4, vaddr=0, memsz=0, align=8, data=dynamic_bytes(tags), covered=True),
+                dict(type=0x61000000, flags=4, vaddr=0, memsz=0, align=8, data=blob, covered=True)]
+    return make_self(segments, 0xfe18)
+
+
+# -- Helpers ------------------------------------------------------------------------------------------------
+
+def put(path, data):
+    path.parent.mkdir(parents=True, exist_ok=True)
+    path.write_bytes(data)
+    return path
+
+
+def text(value):
+    return json.dumps(value, indent=2, ensure_ascii=False) + '\n'
+
+
+def lf(path):
+    """A text file as the module wrote it, with LF: Windows text-mode writes give CRLF, the Rust runner writes \\n."""
+    return path.read_bytes().replace(b'\r\n', b'\n')
+
+
+def quiet(function, *args):
+    """function(*args) without its progress lines on the console."""
+    with contextlib.redirect_stdout(io.StringIO()):
+        return function(*args)
+
+
+def case_folder(name):
+    folder = FIXTURES / name
+    shutil.rmtree(folder, ignore_errors=True)
+    return folder / 'input', folder / 'expected'
+
+
+def stage(game, files):
+    """Writes {relative path: bytes} under game."""
+    for relative, data in files.items():
+        put(game / relative, data)
+    return game
+
+
+# -- Cases --------------------------------------------------------------------------------------------------
+
+EBOOT, IMPORT_NAMES, EBOOT_CODE = eboot_parts()
+LIBC, FIOS = libc_self(), fios_self()
+PARAM_SFO = sfo_bytes({'TITLE_ID': 'CUSA01623', 'TITLE': 'ゴッド・オブ・ウォーIII リマスタード', 'APP_VER': '01.02',
+                       'CONTENT_ID': 'EP9000-CUSA01623_00-GOW3REMASTERED00', **PARAMS})
+GAME_FILES = {'eboot.bin': EBOOT, 'sce_module/libc.prx': LIBC, 'sce_sys/param.sfo': PARAM_SFO,
+              'dvdroot_ps4/PART1.WAD': b'WAD3' + bytes(range(28)), 'dvdroot_ps4/sound/music.bin': bytes(100)}
+
+
+def case_prepare():
+    inputs, expected = case_folder('prepare')
+    stage(inputs, GAME_FILES)
+    out = WORK / 'prepare-out'
+    quiet(prepare_module.prepare, inputs, out)
+    for name in ('boot.bin', 'eboot.elf', 'entry.bin'):
+        put(expected / name, (out / name).read_bytes())
+    put(expected / 'analysis.json', lf(out / 'analysis.json'))
+    return out
+
+
+def case_link(prepared):
+    inputs, expected = case_folder('link')
+    stage(inputs, {'eboot.bin': EBOOT, 'sce_module/libc.prx': LIBC, 'sce_module/libSceFios2.prx': FIOS})
+    relocs = [(0x800, 0, 0x40, 0), (0x818, 1, 0, 0), (0x820, 2, 1, 0)]
+    boot = package(EBOOT_CODE, relocs, IMPORT_NAMES, capabilities=1)
+    put(inputs / 'boot.bin', boot)
+    for linker, outputs in ((link_libc, ('boot-libc.bin', 'libc-link.json')),
+                            (link_modules, ('boot-linked.bin', 'link.json'))):
+        out = WORK / f'{linker.__name__}-out'
+        put(out / 'boot.bin', boot)
+        quiet(linker.link, inputs, out)
+        for name in outputs:
+            put(expected / name, lf(out / name) if name.endswith('.json') else (out / name).read_bytes())
+
+
+def site_entry(site):
+    kinds = {value: name[5:] for name, value in vars(isa_rewrite).items() if name.startswith('KIND_')}
+    modes = {value: name[5:] for name, value in vars(isa_rewrite).items() if name.startswith('MODE_')}
+    return dict(offset=site.offset, length=site.length, kind=kinds[site.kind], width=site.width,
+                mode=modes[site.mode],
+                registers=dict(dst=site.dst, src1=site.src1, src2=site.src2, base=site.base, index=site.index),
+                mem_slot=site.mem_slot, scale=site.scale, mem_flags=site.mem_flags, disp=site.disp,
+                original=site.original.hex(), relocated=site.relocated.hex())
+
+
+def case_isa():
+    inputs, expected = case_folder('isa')
+    code = isa_rewrite.fixture_code()
+    boot = put(inputs / 'boot-linked.bin', boot_linked([(code, len(code), 5)]))
+    out = WORK / 'isa-out'
+    out.mkdir()
+    if quiet(isa_rewrite.main, [str(boot), '--out', str(out)]) != 0:
+        raise SystemExit('isa: the rewrite table could not be made')
+    table = (out / 'isa-rewrite.bin').read_bytes()
+    if table != (ROOT / 'tests/data/isa_fixture.bin').read_bytes():
+        raise SystemExit('isa: the table differs from tests/data/isa_fixture.bin')
+    put(expected / 'isa-rewrite.bin', table)
+    put(expected / 'sites.json', text([site_entry(s) for s in isa_rewrite.scan_segment(code, 0)]).encode())
+
+
+def case_content():
+    inputs, expected = case_folder('content')
+    sfo = put(inputs / 'param.sfo', sfo_bytes({'TITLE_ID': 'CUSA01623', 'APP_VER': '01.02', **PARAMS}))
+    game = stage(WORK / 'content-game', {'sce_sys/param.sfo': sfo.read_bytes()})
+    for sku in ('full', 'trial'):
+        out = WORK / f'content-{sku}'
+        quiet(content_profile.prepare, game, out, sku)
+        put(expected / sku / 'content.bin', (out / 'content.bin').read_bytes())
+        put(expected / sku / 'content-profile.json', lf(out / 'content-profile.json'))
+
+
+def case_patches():
+    inputs, expected = case_folder('patches')
+    tests = SignatureTests('test_sites_found_anywhere_and_rel32_recomputed')
+    tests.setUp()  # the image with the signatures planted; its temporary folder goes at once
+    image = tests.image
+    tests.doCleanups()
+    # One PT_LOAD at file offset 0x100, virtual address 0, as patches.eboot_segments/eboot_image read it.
+    head = struct.pack('<16sHHIQQQIHHHHHH', b'\x7fELF\x02\x01\x01\x09', 2, 62, 1, 0, 64, 0, 0, 64, 56, 1, 0, 0, 0)
+    head += struct.pack('<IIQQQQQQ', 1, 5, 0x100, 0, 0, len(image), len(image), 0x1000)
+    put(inputs / 'eboot.elf', head.ljust(0x100, b'\0') + image)
+    put(inputs / 'eboot.bin', b'synthetic eboot.bin of the patches case\n')
+    put(inputs / 'param.sfo', sfo_bytes({'TITLE_ID': 'CUSA01623', 'APP_VER': '01.02', 'TITLE': 'God of War III'}))
+    xml = SignatureTests.XML.replace('<Patch>', '<Patch>\n  <TitleID><ID>CUSA01623</ID></TitleID>', 1)
+    put(inputs / 'patches.xml', xml.encode())
+    put(inputs / 'mod.xml', ModPatchTests.MOD.encode())
+
+    game = stage(WORK / 'patches-game', {'eboot.bin': (inputs / 'eboot.bin').read_bytes(),
+                                         'sce_sys/param.sfo': (inputs / 'param.sfo').read_bytes()})
+    out = WORK / 'patches-out'
+    put(out / 'eboot.elf', (inputs / 'eboot.elf').read_bytes())
+    saved = patches.GAMES, sys.argv, os.environ.get('SPARTAN_PATCHES_ONLY')
+    patches.GAMES = [({'CUSA01623'}, WORK / 'patches.xml', '01.02', 'God of War III')]
+    put(WORK / 'patches.xml', xml.encode())
+    os.environ['SPARTAN_PATCHES_ONLY'] = '1'
+    sys.argv = ['patches.py', '--out', str(out), '--game-dir', str(game), '--mod-patches', str(inputs / 'mod.xml'),
+                '--extra', 'Found;Call;Missing;Data']
+    try:
+        quiet(patches.main)
+    finally:
+        patches.GAMES, sys.argv = saved[0], saved[1]
+        if saved[2] is None:
+            del os.environ['SPARTAN_PATCHES_ONLY']
+        else:
+            os.environ['SPARTAN_PATCHES_ONLY'] = saved[2]
+    put(expected / 'patches-merged.xml', lf(out / 'patches-merged.xml'))
+    put(expected / 'patches.bin', (out / 'patches.bin').read_bytes())
+    put(expected / 'patch_status.json', lf(out / 'patch_status.json'))
+
+
+def case_graphics():
+    inputs, expected = case_folder('graphics')
+    put(inputs / 'spartanport.ini', b'render_resolution=1440p\nengine_fps=120\n')
+    put(inputs / 'graphics_state.json', b'{}\n')
+    put(inputs / 'edit.json', text(EDIT).encode())
+    work = WORK / 'graphics'
+    work.mkdir()
+    ini, state = work / 'spartanport.ini', work / 'graphics_state.json'
+    shutil.copyfile(inputs / 'spartanport.ini', ini)
+    shutil.copyfile(inputs / 'graphics_state.json', state)
+    for step in ('good', 'tried', 'reverted'):
+        if step == 'tried':
+            graphics_options.write_keys(ini, EDIT)  # the in-game menu asking for a restart
+        options, _ = graphics_options.prepare(ini, state)
+        put(expected / step / 'spartanport.ini', lf(ini))
+        put(expected / step / 'graphics_state.json', lf(state))
+        put(expected / step / 'environment.json', text(graphics_options.environment(options)).encode())
+
+
+def test_images():
+    """The five 64 x 64 RGBA test images."""
+    size = 64
+    noise = random.Random(20260101)
+    drawings = {
+        'gradient': lambda x, y: (x * 4, y * 4, (x + y) * 2, 255),
+        'edges': lambda x, y: ((255, 255, 255, 255) if ((x + 1) // 5 + (y + 3) // 7 + (x == y) * 2) % 2 == 0
+                               else (20, 30, 40, 255)),
+        'alpha': lambda x, y: (230, 90 + y * 2, 40, x * 4),
+        'noise': lambda x, y: tuple(noise.randrange(256) for _ in range(4)),
+        'flat': lambda x, y: (200, 100, 50, 255),
+    }
+    images = {}
+    for name, draw in drawings.items():
+        image = Image.new('RGBA', (size, size))
+        image.putdata([draw(x, y) for y in range(size) for x in range(size)])
+        images[name] = image
+    return images
+
+
+def strips(image, fourcc):
+    """glyphs.encode_region's 4-row strips of the whole picture, DDS headers stripped, concatenated."""
+    image = image.convert('RGBA' if fourcc == 'DXT5' else 'RGB')
+    width, height = image.size
+    encoded = b''
+    for y in range(0, height, 4):
+        strip = io.BytesIO()
+        image.crop((0, y, width, min(y + 4, height))).save(strip, 'DDS', pixel_format=fourcc)
+        encoded += strip.getvalue()[128:]
+    return encoded
+
+
+def encode_region_blocks(image, fourcc):
+    """The same bytes through glyphs.encode_region itself, over a texture holding just the top level."""
+    block = 16 if fourcc == 'DXT5' else 8
+    width, height = image.size
+    data = bytearray(128 + (width // 4) * (height // 4) * block)
+    struct.pack_into('<II', data, 12, height, width)
+    glyphs.encode_region(data, 0, len(data), image, fourcc, (0, 0, width, height))
+    return bytes(data[128:])
+
+
+def case_dxt():
+    inputs, expected = case_folder('dxt')
+    for name, image in test_images().items():
+        inputs.mkdir(parents=True, exist_ok=True)
+        image.save(inputs / f'{name}.png')
+        for fourcc in ('DXT1', 'DXT5'):
+            blocks = strips(image, fourcc)
+            if blocks != encode_region_blocks(image, fourcc):
+                raise SystemExit(f'dxt: {name} {fourcc} differs from glyphs.encode_region')
+            put(expected / f'{name}.{fourcc.lower()}', blocks)
+
+
+def case_icon():
+    _, expected = case_folder('icon')
+    expected.mkdir(parents=True)
+    with Image.open(ROOT / 'launcher' / 'spartanport.png') as icon:  # run.py: the window icon
+        icon.convert('RGBA').resize((64, 64), Image.LANCZOS).save(expected / 'window_icon.bmp')
+
+
+def check_no_temp_folder():
+    for path in FIXTURES.rglob('*'):
+        if path.is_file():
+            data = path.read_bytes()
+            for spelling in {str(WORK), str(WORK).replace('\\', '/'), WORK.name}:
+                if spelling.encode() in data:
+                    raise SystemExit(f'{path.relative_to(ROOT)} holds the temporary folder {spelling}')
+
+
+if __name__ == '__main__':
+    try:
+        FIXTURES.mkdir(parents=True, exist_ok=True)
+        prepared = case_prepare()
+        for case in (lambda: case_link(prepared), case_isa, case_content, case_patches, case_graphics, case_dxt,
+                     case_icon):
+            case()
+        check_no_temp_folder()
+        for folder in sorted(p for p in FIXTURES.iterdir() if p.is_dir()):
+            print('wrote', folder.relative_to(ROOT))
+    finally:
+        shutil.rmtree(WORK, ignore_errors=True)