diff --git a/host/tests/fixtures/esbuild/app.tsx b/host/tests/fixtures/esbuild/app.tsx
new file mode 100644
index 0000000..1d75aa5
--- /dev/null
+++ b/host/tests/fixtures/esbuild/app.tsx
@@ -0,0 +1,8 @@
+// This fixture checks TSX, package resolution, and browser rendering.
+import { render } from 'preact';
+
+const message: string = 'Hello from WASI';
+function App() {
+  return <main><h1>{message}</h1><p>Preact + TypeScript</p></main>;
+}
+render(<App />, document.getElementById('app')!);
diff --git a/host/tests/fixtures/esbuild/package-lock.json b/host/tests/fixtures/esbuild/package-lock.json
new file mode 100644
index 0000000..a25435d
--- /dev/null
+++ b/host/tests/fixtures/esbuild/package-lock.json
@@ -0,0 +1,210 @@
+{
+  "name": "s6-esbuild-fixture",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "s6-esbuild-fixture",
+      "dependencies": {
+        "linkedom": "0.18.12",
+        "preact": "10.27.2"
+      }
+    },
+    "node_modules/boolbase": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/boolbase/-/boolbase-1.0.0.tgz",
+      "integrity": "sha512-JZOSA7Mo9sNGB8+UjSgzdLtokWAky1zbztM3WRLCbZ70/3cTANmQmOdR7y2g+J0e2WXywy1yS468tY+IruqEww==",
+      "license": "ISC"
+    },
+    "node_modules/css-select": {
+      "version": "5.2.2",
+      "resolved": "https://registry.npmjs.org/css-select/-/css-select-5.2.2.tgz",
+      "integrity": "sha512-TizTzUddG/xYLA3NXodFM0fSbNizXjOKhqiQQwvhlspadZokn1KDy0NZFS0wuEubIYAV5/c1/lAr0TaaFXEXzw==",
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "boolbase": "^1.0.0",
+        "css-what": "^6.1.0",
+        "domhandler": "^5.0.2",
+        "domutils": "^3.0.1",
+        "nth-check": "^2.0.1"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/fb55"
+      }
+    },
+    "node_modules/css-what": {
+      "version": "6.2.2",
+      "resolved": "https://registry.npmjs.org/css-what/-/css-what-6.2.2.tgz",
+      "integrity": "sha512-u/O3vwbptzhMs3L1fQE82ZSLHQQfto5gyZzwteVIEyeaY5Fc7R4dapF/BvRoSYFeqfBk4m0V1Vafq5Pjv25wvA==",
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">= 6"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/fb55"
+      }
+    },
+    "node_modules/cssom": {
+      "version": "0.5.0",
+      "resolved": "https://registry.npmjs.org/cssom/-/cssom-0.5.0.tgz",
+      "integrity": "sha512-iKuQcq+NdHqlAcwUY0o/HL69XQrUaQdMjmStJ8JFmUaiiQErlhrmuigkg/CU4E2J0IyUKUrMAgl36TvN67MqTw==",
+      "license": "MIT"
+    },
+    "node_modules/dom-serializer": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/dom-serializer/-/dom-serializer-2.0.0.tgz",
+      "integrity": "sha512-wIkAryiqt/nV5EQKqQpo3SToSOV9J0DnbJqwK7Wv/Trc92zIAYZ4FlMu+JPFW1DfGFt81ZTCGgDEabffXeLyJg==",
+      "license": "MIT",
+      "dependencies": {
+        "domelementtype": "^2.3.0",
+        "domhandler": "^5.0.2",
+        "entities": "^4.2.0"
+      },
+      "funding": {
+        "url": "https://github.com/cheeriojs/dom-serializer?sponsor=1"
+      }
+    },
+    "node_modules/domelementtype": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/domelementtype/-/domelementtype-2.3.0.tgz",
+      "integrity": "sha512-OLETBj6w0OsagBwdXnPdN0cnMfF9opN69co+7ZrbfPGrdpPVNBUj02spi6B1N7wChLQiPn4CSH/zJvXw56gmHw==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/fb55"
+        }
+      ],
+      "license": "BSD-2-Clause"
+    },
+    "node_modules/domhandler": {
+      "version": "5.0.3",
+      "resolved": "https://registry.npmjs.org/domhandler/-/domhandler-5.0.3.tgz",
+      "integrity": "sha512-cgwlv/1iFQiFnU96XXgROh8xTeetsnJiDsTc7TYCLFd9+/WNkIqPTxiM/8pSd8VIrhXGTf1Ny1q1hquVqDJB5w==",
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "domelementtype": "^2.3.0"
+      },
+      "engines": {
+        "node": ">= 4"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/domhandler?sponsor=1"
+      }
+    },
+    "node_modules/domutils": {
+      "version": "3.2.2",
+      "resolved": "https://registry.npmjs.org/domutils/-/domutils-3.2.2.tgz",
+      "integrity": "sha512-6kZKyUajlDuqlHKVX1w7gyslj9MPIXzIFiz/rGu35uC1wMi+kMhQwGhl4lt9unC9Vb9INnY9Z3/ZA3+FhASLaw==",
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "dom-serializer": "^2.0.0",
+        "domelementtype": "^2.3.0",
+        "domhandler": "^5.0.3"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/domutils?sponsor=1"
+      }
+    },
+    "node_modules/entities": {
+      "version": "4.5.0",
+      "resolved": "https://registry.npmjs.org/entities/-/entities-4.5.0.tgz",
+      "integrity": "sha512-V0hjH4dGPh9Ao5p0MoRY6BVqtwCjhz6vI5LT8AJ55H+4g9/4vbHx1I54fS0XuclLhDHArPQCiMjDxjaL8fPxhw==",
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=0.12"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/entities?sponsor=1"
+      }
+    },
+    "node_modules/html-escaper": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/html-escaper/-/html-escaper-3.0.3.tgz",
+      "integrity": "sha512-RuMffC89BOWQoY0WKGpIhn5gX3iI54O6nRA0yC124NYVtzjmFWBIiFd8M0x+ZdX0P9R4lADg1mgP8C7PxGOWuQ==",
+      "license": "MIT"
+    },
+    "node_modules/htmlparser2": {
+      "version": "10.1.0",
+      "resolved": "https://registry.npmjs.org/htmlparser2/-/htmlparser2-10.1.0.tgz",
+      "integrity": "sha512-VTZkM9GWRAtEpveh7MSF6SjjrpNVNNVJfFup7xTY3UpFtm67foy9HDVXneLtFVt4pMz5kZtgNcvCniNFb1hlEQ==",
+      "funding": [
+        "https://github.com/fb55/htmlparser2?sponsor=1",
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/fb55"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "domelementtype": "^2.3.0",
+        "domhandler": "^5.0.3",
+        "domutils": "^3.2.2",
+        "entities": "^7.0.1"
+      }
+    },
+    "node_modules/htmlparser2/node_modules/entities": {
+      "version": "7.0.1",
+      "resolved": "https://registry.npmjs.org/entities/-/entities-7.0.1.tgz",
+      "integrity": "sha512-TWrgLOFUQTH994YUyl1yT4uyavY5nNB5muff+RtWaqNVCAK408b5ZnnbNAUEWLTCpum9w6arT70i1XdQ4UeOPA==",
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=0.12"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/entities?sponsor=1"
+      }
+    },
+    "node_modules/linkedom": {
+      "version": "0.18.12",
+      "resolved": "https://registry.npmjs.org/linkedom/-/linkedom-0.18.12.tgz",
+      "integrity": "sha512-jalJsOwIKuQJSeTvsgzPe9iJzyfVaEJiEXl+25EkKevsULHvMJzpNqwvj1jOESWdmgKDiXObyjOYwlUqG7wo1Q==",
+      "license": "ISC",
+      "dependencies": {
+        "css-select": "^5.1.0",
+        "cssom": "^0.5.0",
+        "html-escaper": "^3.0.3",
+        "htmlparser2": "^10.0.0",
+        "uhyphen": "^0.2.0"
+      },
+      "engines": {
+        "node": ">=16"
+      },
+      "peerDependencies": {
+        "canvas": ">= 2"
+      },
+      "peerDependenciesMeta": {
+        "canvas": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/nth-check": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/nth-check/-/nth-check-2.1.1.tgz",
+      "integrity": "sha512-lqjrjmaOoAnWfMmBPL+XNnynZh2+swxiX3WUE0s4yEHI6m+AwrK2UZOimIRl3X/4QctVqS8AiZjFqyOGrMXb/w==",
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "boolbase": "^1.0.0"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/nth-check?sponsor=1"
+      }
+    },
+    "node_modules/preact": {
+      "version": "10.27.2",
+      "resolved": "https://registry.npmjs.org/preact/-/preact-10.27.2.tgz",
+      "integrity": "sha512-5SYSgFKSyhCbk6SrXyMpqjb5+MQBgfvEKE/OC+PujcY34sOpqtr+0AZQtPYx5IA6VxynQ7rUPCtKzyovpj9Bpg==",
+      "license": "MIT",
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/preact"
+      }
+    },
+    "node_modules/uhyphen": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/uhyphen/-/uhyphen-0.2.0.tgz",
+      "integrity": "sha512-qz3o9CHXmJJPGBdqzab7qAYuW8kQGKNEuoHFYrBwV6hWIMcpAmxDLXojcHfFr9US1Pe6zUswEIJIbLI610fuqA==",
+      "license": "ISC"
+    }
+  }
+}
diff --git a/host/tests/fixtures/esbuild/package.json b/host/tests/fixtures/esbuild/package.json
new file mode 100644
index 0000000..983e56a
--- /dev/null
+++ b/host/tests/fixtures/esbuild/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "s6-esbuild-fixture",
+  "private": true,
+  "type": "module",
+  "dependencies": {
+    "preact": "10.27.2",
+    "linkedom": "0.18.12"
+  }
+}
diff --git a/host/tests/fixtures/shell/corpus.sh b/host/tests/fixtures/shell/corpus.sh
new file mode 100644
index 0000000..14e3c18
--- /dev/null
+++ b/host/tests/fixtures/shell/corpus.sh
@@ -0,0 +1,18 @@
+cd work
+printf 'pwd=%s\n' "$(pwd)"
+printf 'upper=%s\n' "$(cat f | tr a-z A-Z)"
+ls *.txt | wc -l
+( cd sub && pwd )
+cat <<'EOF'
+$HOME stays literal
+EOF
+cat missing 2>/dev/null >> log
+cat f 2>/dev/null >> log
+cat log
+wc -l < file
+for f in *; do printf 'entry=%s\n' "$f"; done
+false || echo ok
+false
+echo $?
+( cd sub && cd ../../other && pwd && cd ../work && pwd )
+yes | head -n 2
diff --git a/host/tests/it/process.rs b/host/tests/it/process.rs
index 1c35792..38110c8 100644
--- a/host/tests/it/process.rs
+++ b/host/tests/it/process.rs
@@ -182,7 +182,7 @@ mod features {
             7
         );
         for name in ["app.tsx", "package.json", "package-lock.json"] {
-            std::fs::copy(repo().join("spikes/s6-esbuild").join(name), root.join(name)).unwrap();
+            std::fs::copy(repo().join("host/tests/fixtures/esbuild").join(name), root.join(name)).unwrap();
         }
         assert!(
             std::process::Command::new("cp")
@@ -566,7 +566,7 @@ async fn corpus_matches_bash() {
     warm(&runtime).await;
     let native = tempfile::tempdir().unwrap();
     fixture(native.path());
-    let script = std::fs::read_to_string(repo().join("spikes/s2-shell/corpus.sh")).unwrap();
+    let script = std::fs::read_to_string(repo().join("host/tests/fixtures/shell/corpus.sh")).unwrap();
     let result = std::process::Command::new("bash")
         .args(["--noprofile", "--norc", "-c", &script])
         .current_dir(native.path())