diff --git a/package-lock.json b/package-lock.json
index cf6e191..e6d5dae 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,18 +1,20 @@
 {
   "name": "context-compression-engine",
-  "version": "1.3.0",
+  "version": "1.4.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "context-compression-engine",
-      "version": "1.3.0",
+      "version": "1.4.0",
       "license": "AGPL-3.0-only",
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         "@eslint/js": "^10.0.1",
         "@google/genai": "^1.46.0",
+        "@types/better-sqlite3": "^7.6.13",
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+        "better-sqlite3": "^12.8.0",
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         "eslint": "^10.0.2",
         "openai": "^6.25.0",
@@ -1291,6 +1293,16 @@
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+      "resolved": "https://registry.npmjs.org/@types/better-sqlite3/-/better-sqlite3-7.6.13.tgz",
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+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@types/chai": {
       "version": "5.2.3",
       "resolved": "https://registry.npmjs.org/@types/chai/-/chai-5.2.3.tgz",
@@ -1876,6 +1888,21 @@
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       "license": "MIT"
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+      "version": "12.8.0",
+      "resolved": "https://registry.npmjs.org/better-sqlite3/-/better-sqlite3-12.8.0.tgz",
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+      "dev": true,
+      "hasInstallScript": true,
+      "license": "MIT",
+      "dependencies": {
+        "bindings": "^1.5.0",
+        "prebuild-install": "^7.1.1"
+      },
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       "version": "9.3.1",
       "resolved": "https://registry.npmjs.org/bignumber.js/-/bignumber.js-9.3.1.tgz",
@@ -1886,6 +1913,28 @@
         "node": "*"
       }
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+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/bindings/-/bindings-1.5.0.tgz",
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+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "file-uri-to-path": "1.0.0"
+      }
+    },
+    "node_modules/bl": {
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+      "resolved": "https://registry.npmjs.org/bl/-/bl-4.1.0.tgz",
+      "integrity": "sha512-1W07cM9gS6DcLperZfFSj+bWLtaPGSOHWhPiGzXmvVJbRLdG82sH/Kn8EtW1VqWVA54AKf2h5k5BbnIbwF3h6w==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "buffer": "^5.5.0",
+        "inherits": "^2.0.4",
+        "readable-stream": "^3.4.0"
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       "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-5.0.3.tgz",
@@ -1899,6 +1948,31 @@
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+    "node_modules/buffer": {
+      "version": "5.7.1",
+      "resolved": "https://registry.npmjs.org/buffer/-/buffer-5.7.1.tgz",
+      "integrity": "sha512-EHcyIPBQ4BSGlvjB16k5KgAJ27CIsHY/2JBmCRReo48y9rQ3MaUzWX3KVlBa4U7MyX02HdVj0K7C3WaB3ju7FQ==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/feross"
+        },
+        {
+          "type": "patreon",
+          "url": "https://www.patreon.com/feross"
+        },
+        {
+          "type": "consulting",
+          "url": "https://feross.org/support"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "base64-js": "^1.3.1",
+        "ieee754": "^1.1.13"
+      }
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@@ -1943,6 +2017,13 @@
         "node": ">=10"
       }
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+    "node_modules/chownr": {
+      "version": "1.1.4",
+      "resolved": "https://registry.npmjs.org/chownr/-/chownr-1.1.4.tgz",
+      "integrity": "sha512-jJ0bqzaylmJtVnNgzTeSOs8DPavpbYgEr/b0YL8/2GO3xJEhInFmhKMUnEJQjZumK7KXGFhUy89PrsJWlakBVg==",
+      "dev": true,
+      "license": "ISC"
+    },
     "node_modules/cjs-module-lexer": {
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       "resolved": "https://registry.npmjs.org/cjs-module-lexer/-/cjs-module-lexer-1.4.3.tgz",
@@ -2080,6 +2161,32 @@
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       }
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+    "node_modules/decompress-response": {
+      "version": "6.0.0",
+      "resolved": "https://registry.npmjs.org/decompress-response/-/decompress-response-6.0.0.tgz",
+      "integrity": "sha512-aW35yZM6Bb/4oJlZncMH2LCoZtJXTRxES17vE3hoRiowU2kWHaJKFkSBDnDR+cm9J+9QhXmREyIfv0pji9ejCQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "mimic-response": "^3.1.0"
+      },
+      "engines": {
+        "node": ">=10"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/sindresorhus"
+      }
+    },
+    "node_modules/deep-extend": {
+      "version": "0.6.0",
+      "resolved": "https://registry.npmjs.org/deep-extend/-/deep-extend-0.6.0.tgz",
+      "integrity": "sha512-LOHxIOaPYdHlJRtCQfDIVZtfw/ufM8+rVj649RIHzcm/vGwQRXFt6OPqIFWsm2XEMrNIEtWR64sY1LEKD2vAOA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=4.0.0"
+      }
+    },
     "node_modules/deep-is": {
       "version": "0.1.4",
       "resolved": "https://registry.npmjs.org/deep-is/-/deep-is-0.1.4.tgz",
@@ -2121,6 +2228,16 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/end-of-stream": {
+      "version": "1.4.5",
+      "resolved": "https://registry.npmjs.org/end-of-stream/-/end-of-stream-1.4.5.tgz",
+      "integrity": "sha512-ooEGc6HP26xXq/N+GCGOT0JKCLDGrq2bQUZrQ7gyrJiZANJ/8YDTxTpQBXGMn+WbIQXNVpyWymm7KYVICQnyOg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "once": "^1.4.0"
+      }
+    },
     "node_modules/environment": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/environment/-/environment-1.1.0.tgz",
@@ -2368,6 +2485,16 @@
         "node": ">=0.10.0"
       }
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+    "node_modules/expand-template": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/expand-template/-/expand-template-2.0.3.tgz",
+      "integrity": "sha512-XYfuKMvj4O35f/pOXLObndIRvyQ+/+6AhODh+OKWj9S9498pHHn/IMszH+gt0fBCRWMNfk1ZSp5x3AifmnI2vg==",
+      "dev": true,
+      "license": "(MIT OR WTFPL)",
+      "engines": {
+        "node": ">=6"
+      }
+    },
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@@ -2468,6 +2595,13 @@
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       }
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+    "node_modules/file-uri-to-path": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/file-uri-to-path/-/file-uri-to-path-1.0.0.tgz",
+      "integrity": "sha512-0Zt+s3L7Vf1biwWZ29aARiVYLx7iMGnEUl9x33fbB/j3jR81u/O2LbqK+Bm1CDSNDKVtJ/YjwY7TUd5SkeLQLw==",
+      "dev": true,
+      "license": "MIT"
+    },
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       "resolved": "https://registry.npmjs.org/find-up/-/find-up-5.0.0.tgz",
@@ -2519,6 +2653,13 @@
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+    "node_modules/fs-constants": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/fs-constants/-/fs-constants-1.0.0.tgz",
+      "integrity": "sha512-y6OAwoSIf7FyjMIv94u+b5rdheZEjzR63GTyZJm5qh4Bi+2YgwLCcI/fPFZkL5PSixOt6ZNKm+w+Hfp/Bciwow==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/fsevents": {
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       "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-2.3.3.tgz",
@@ -2574,6 +2715,13 @@
         "node": "6.* || 8.* || >= 10.*"
       }
     },
+    "node_modules/github-from-package": {
+      "version": "0.0.0",
+      "resolved": "https://registry.npmjs.org/github-from-package/-/github-from-package-0.0.0.tgz",
+      "integrity": "sha512-SyHy3T1v2NUXn29OsWdxmK6RwHD+vkj3v8en8AOBZ1wBQ/hCAQ5bAQTD02kW4W9tUp/3Qh6J8r9EvntiyCmOOw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/glob-parent": {
       "version": "6.0.2",
       "resolved": "https://registry.npmjs.org/glob-parent/-/glob-parent-6.0.2.tgz",
@@ -2656,6 +2804,27 @@
         "node": ">= 14"
       }
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+    "node_modules/ieee754": {
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/ieee754/-/ieee754-1.2.1.tgz",
+      "integrity": "sha512-dcyqhDvX1C46lXZcVqCpK+FtMRQVdIMN6/Df5js2zouUsqG7I6sFxitIC+7KYK29KdXOLHdu9zL4sFnoVQnqaA==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/feross"
+        },
+        {
+          "type": "patreon",
+          "url": "https://www.patreon.com/feross"
+        },
+        {
+          "type": "consulting",
+          "url": "https://feross.org/support"
+        }
+      ],
+      "license": "BSD-3-Clause"
+    },
     "node_modules/ignore": {
       "version": "5.3.2",
       "resolved": "https://registry.npmjs.org/ignore/-/ignore-5.3.2.tgz",
@@ -2676,6 +2845,20 @@
         "node": ">=0.8.19"
       }
     },
+    "node_modules/inherits": {
+      "version": "2.0.4",
+      "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+      "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
+      "dev": true,
+      "license": "ISC"
+    },
+    "node_modules/ini": {
+      "version": "1.3.8",
+      "resolved": "https://registry.npmjs.org/ini/-/ini-1.3.8.tgz",
+      "integrity": "sha512-JV/yugV2uzW5iMRSiZAyDtQd+nxtUnjeLt0acNdw98kKLrvuRVyB80tsREOE7yvGVgalhZ6RNXCmEHkUKBKxew==",
+      "dev": true,
+      "license": "ISC"
+    },
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       "resolved": "https://registry.npmjs.org/is-extglob/-/is-extglob-2.1.1.tgz",
@@ -3220,6 +3403,19 @@
         "url": "https://github.com/chalk/chalk?sponsor=1"
       }
     },
+    "node_modules/mimic-response": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/mimic-response/-/mimic-response-3.1.0.tgz",
+      "integrity": "sha512-z0yWI+4FDrrweS8Zmt4Ej5HdJmky15+L2e6Wgn3+iK5fWzb6T3fhNFq2+MeTRb064c6Wr4N/wv0DzQTjNzHNGQ==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=10"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/sindresorhus"
+      }
+    },
     "node_modules/minimatch": {
       "version": "10.2.4",
       "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-10.2.4.tgz",
@@ -3236,6 +3432,23 @@
         "url": "https://github.com/sponsors/isaacs"
       }
     },
+    "node_modules/minimist": {
+      "version": "1.2.8",
+      "resolved": "https://registry.npmjs.org/minimist/-/minimist-1.2.8.tgz",
+      "integrity": "sha512-2yyAR8qBkN3YuheJanUpWC5U3bb5osDywNB8RzDVlDwDHbocAJveqqj1u8+SVD7jkWT4yvsHCpWqqWqAxb0zCA==",
+      "dev": true,
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/mkdirp-classic": {
+      "version": "0.5.3",
+      "resolved": "https://registry.npmjs.org/mkdirp-classic/-/mkdirp-classic-0.5.3.tgz",
+      "integrity": "sha512-gKLcREMhtuZRwRAfqP3RFW+TK4JqApVBtOIftVgjuABpAtpxhPGaDcfvbhNvD0B8iD1oUr/txX35NjcaY6Ns/A==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/mri": {
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       "resolved": "https://registry.npmjs.org/mri/-/mri-1.2.0.tgz",
@@ -3284,6 +3497,13 @@
         "node": "^10 || ^12 || ^13.7 || ^14 || >=15.0.1"
       }
     },
+    "node_modules/napi-build-utils": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/napi-build-utils/-/napi-build-utils-2.0.0.tgz",
+      "integrity": "sha512-GEbrYkbfF7MoNaoh2iGG84Mnf/WZfB0GdGEsM8wz7Expx/LlWf5U8t9nvJKXSp3qr5IsEbK04cBGhol/KwOsWA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/natural-compare": {
       "version": "1.4.0",
       "resolved": "https://registry.npmjs.org/natural-compare/-/natural-compare-1.4.0.tgz",
@@ -3291,6 +3511,19 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/node-abi": {
+      "version": "3.89.0",
+      "resolved": "https://registry.npmjs.org/node-abi/-/node-abi-3.89.0.tgz",
+      "integrity": "sha512-6u9UwL0HlAl21+agMN3YAMXcKByMqwGx+pq+P76vii5f7hTPtKDp08/H9py6DY+cfDw7kQNTGEj/rly3IgbNQA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "semver": "^7.3.5"
+      },
+      "engines": {
+        "node": ">=10"
+      }
+    },
     "node_modules/node-domexception": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/node-domexception/-/node-domexception-1.0.0.tgz",
@@ -3368,6 +3601,16 @@
       ],
       "license": "MIT"
     },
+    "node_modules/once": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
+      "integrity": "sha512-lNaJgI+2Q5URQBkccEKHTQOPaXdUxnZZElQTZY0MFUAuaEqe1E+Nyvgdz/aIyNi6Z9MzO5dv1H8n58/GELp3+w==",
+      "dev": true,
+      "license": "ISC",
+      "dependencies": {
+        "wrappy": "1"
+      }
+    },
     "node_modules/openai": {
       "version": "6.32.0",
       "resolved": "https://registry.npmjs.org/openai/-/openai-6.32.0.tgz",
@@ -3561,6 +3804,34 @@
         "node": "^10 || ^12 || >=14"
       }
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+    "node_modules/prebuild-install": {
+      "version": "7.1.3",
+      "resolved": "https://registry.npmjs.org/prebuild-install/-/prebuild-install-7.1.3.tgz",
+      "integrity": "sha512-8Mf2cbV7x1cXPUILADGI3wuhfqWvtiLA1iclTDbFRZkgRQS0NqsPZphna9V+HyTEadheuPmjaJMsbzKQFOzLug==",
+      "deprecated": "No longer maintained. Please contact the author of the relevant native addon; alternatives are available.",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "detect-libc": "^2.0.0",
+        "expand-template": "^2.0.3",
+        "github-from-package": "0.0.0",
+        "minimist": "^1.2.3",
+        "mkdirp-classic": "^0.5.3",
+        "napi-build-utils": "^2.0.0",
+        "node-abi": "^3.3.0",
+        "pump": "^3.0.0",
+        "rc": "^1.2.7",
+        "simple-get": "^4.0.0",
+        "tar-fs": "^2.0.0",
+        "tunnel-agent": "^0.6.0"
+      },
+      "bin": {
+        "prebuild-install": "bin.js"
+      },
+      "engines": {
+        "node": ">=10"
+      }
+    },
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@@ -3634,6 +3905,17 @@
         "url": "https://bjornlu.com/sponsor"
       }
     },
+    "node_modules/pump": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/pump/-/pump-3.0.4.tgz",
+      "integrity": "sha512-VS7sjc6KR7e1ukRFhQSY5LM2uBWAUPiOPa/A3mkKmiMwSmRFUITt0xuj+/lesgnCv+dPIEYlkzrcyXgquIHMcA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "end-of-stream": "^1.1.0",
+        "once": "^1.3.1"
+      }
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       "resolved": "https://registry.npmjs.org/punycode/-/punycode-2.3.1.tgz",
@@ -3644,6 +3926,37 @@
         "node": ">=6"
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+      "resolved": "https://registry.npmjs.org/rc/-/rc-1.2.8.tgz",
+      "integrity": "sha512-y3bGgqKj3QBdxLbLkomlohkvsA8gdAiUQlSBJnBhfn+BPxg4bc62d8TcBW15wavDfgexCgccckhcZvywyQYPOw==",
+      "dev": true,
+      "license": "(BSD-2-Clause OR MIT OR Apache-2.0)",
+      "dependencies": {
+        "deep-extend": "^0.6.0",
+        "ini": "~1.3.0",
+        "minimist": "^1.2.0",
+        "strip-json-comments": "~2.0.1"
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+      "bin": {
+        "rc": "cli.js"
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+    "node_modules/readable-stream": {
+      "version": "3.6.2",
+      "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-3.6.2.tgz",
+      "integrity": "sha512-9u/sniCrY3D5WdsERHzHE4G2YCXqoG5FTHUiCC4SIbr6XcLZBY05ya9EKjYek9O5xOAwjGq+1JdGBAS7Q9ScoA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "inherits": "^2.0.3",
+        "string_decoder": "^1.1.1",
+        "util-deprecate": "^1.0.1"
+      },
+      "engines": {
+        "node": ">= 6"
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@@ -3775,6 +4088,53 @@
       "dev": true,
       "license": "ISC"
     },
+    "node_modules/simple-concat": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/simple-concat/-/simple-concat-1.0.1.tgz",
+      "integrity": "sha512-cSFtAPtRhljv69IK0hTVZQ+OfE9nePi/rtJmw5UjHeVyVroEqJXP1sFztKUy1qU+xvz3u/sfYJLa947b7nAN2Q==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/feross"
+        },
+        {
+          "type": "patreon",
+          "url": "https://www.patreon.com/feross"
+        },
+        {
+          "type": "consulting",
+          "url": "https://feross.org/support"
+        }
+      ],
+      "license": "MIT"
+    },
+    "node_modules/simple-get": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/simple-get/-/simple-get-4.0.1.tgz",
+      "integrity": "sha512-brv7p5WgH0jmQJr1ZDDfKDOSeWWg+OVypG99A/5vYGPqJ6pxiaHLy8nxtFjBA7oMa01ebA9gfh1uMCFqOuXxvA==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/feross"
+        },
+        {
+          "type": "patreon",
+          "url": "https://www.patreon.com/feross"
+        },
+        {
+          "type": "consulting",
+          "url": "https://feross.org/support"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "decompress-response": "^6.0.0",
+        "once": "^1.3.1",
+        "simple-concat": "^1.0.0"
+      }
+    },
     "node_modules/skin-tone": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/skin-tone/-/skin-tone-2.0.0.tgz",
@@ -3812,6 +4172,16 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/string_decoder": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.3.0.tgz",
+      "integrity": "sha512-hkRX8U1WjJFd8LsDJ2yQ/wWWxaopEsABU1XfkM8A+j0+85JAGppt16cr1Whg6KIbb4okU6Mql6BOj+uup/wKeA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "safe-buffer": "~5.2.0"
+      }
+    },
     "node_modules/string-width": {
       "version": "4.2.3",
       "resolved": "https://registry.npmjs.org/string-width/-/string-width-4.2.3.tgz",
@@ -3850,6 +4220,16 @@
         "node": ">=8"
       }
     },
+    "node_modules/strip-json-comments": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-2.0.1.tgz",
+      "integrity": "sha512-4gB8na07fecVVkOI6Rs4e7T6NOTki5EmL7TUduTs6bu3EdnSycntVJ4re8kgZA+wx9IueI2Y11bfbgwtzuE0KQ==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=0.10.0"
+      }
+    },
     "node_modules/supports-color": {
       "version": "7.2.0",
       "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-7.2.0.tgz",
@@ -3880,6 +4260,36 @@
         "url": "https://github.com/chalk/supports-hyperlinks?sponsor=1"
       }
     },
+    "node_modules/tar-fs": {
+      "version": "2.1.4",
+      "resolved": "https://registry.npmjs.org/tar-fs/-/tar-fs-2.1.4.tgz",
+      "integrity": "sha512-mDAjwmZdh7LTT6pNleZ05Yt65HC3E+NiQzl672vQG38jIrehtJk/J3mNwIg+vShQPcLF/LV7CMnDW6vjj6sfYQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "chownr": "^1.1.1",
+        "mkdirp-classic": "^0.5.2",
+        "pump": "^3.0.0",
+        "tar-stream": "^2.1.4"
+      }
+    },
+    "node_modules/tar-stream": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/tar-stream/-/tar-stream-2.2.0.tgz",
+      "integrity": "sha512-ujeqbceABgwMZxEJnk2HDY2DlnUZ+9oEcb1KzTVfYHio0UE6dG71n60d8D2I4qNvleWrrXpmjpt7vZeF1LnMZQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "bl": "^4.0.3",
+        "end-of-stream": "^1.4.1",
+        "fs-constants": "^1.0.0",
+        "inherits": "^2.0.3",
+        "readable-stream": "^3.1.1"
+      },
+      "engines": {
+        "node": ">=6"
+      }
+    },
     "node_modules/thenify": {
       "version": "3.3.1",
       "resolved": "https://registry.npmjs.org/thenify/-/thenify-3.3.1.tgz",
@@ -3968,6 +4378,19 @@
       "license": "0BSD",
       "optional": true
     },
+    "node_modules/tunnel-agent": {
+      "version": "0.6.0",
+      "resolved": "https://registry.npmjs.org/tunnel-agent/-/tunnel-agent-0.6.0.tgz",
+      "integrity": "sha512-McnNiV1l8RYeY8tBgEpuodCC1mLUdbSN+CYBL7kJsJNInOP8UjDDEwdk6Mw60vdLLrr5NHKZhMAOSrR2NZuQ+w==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "safe-buffer": "^5.0.1"
+      },
+      "engines": {
+        "node": "*"
+      }
+    },
     "node_modules/type-check": {
       "version": "0.4.0",
       "resolved": "https://registry.npmjs.org/type-check/-/type-check-0.4.0.tgz",
@@ -4046,6 +4469,13 @@
         "punycode": "^2.1.0"
       }
     },
+    "node_modules/util-deprecate": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz",
+      "integrity": "sha512-EPD5q1uXyFxJpCrLnCc1nHnq3gOa6DZBocAIiI2TaSCA7VCJ1UJDMagCzIkXNsUYfD1daK//LTEQ8xiIbrHtcw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/validate-npm-package-name": {
       "version": "5.0.1",
       "resolved": "https://registry.npmjs.org/validate-npm-package-name/-/validate-npm-package-name-5.0.1.tgz",
@@ -4287,6 +4717,13 @@
         "url": "https://github.com/chalk/wrap-ansi?sponsor=1"
       }
     },
+    "node_modules/wrappy": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
+      "integrity": "sha512-l4Sp/DRseor9wL6EvV2+TuQn63dMkPjZ/sp9XkghTEbV9KlPS1xUsZ3u7/IQO4wxtcFB4bgpQPRcR3QCvezPcQ==",
+      "dev": true,
+      "license": "ISC"
+    },
     "node_modules/ws": {
       "version": "8.19.0",
       "resolved": "https://registry.npmjs.org/ws/-/ws-8.19.0.tgz",
diff --git a/package.json b/package.json
index ffc6e02..48858db 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "context-compression-engine",
-  "version": "1.3.0",
+  "version": "1.4.0",
   "description": "Lossless context compression engine for LLMs",
   "type": "module",
   "engines": {
@@ -67,11 +67,21 @@
   "bugs": {
     "url": "https://github.com/SimplyLiz/ContextCompressionEngine/issues"
   },
+  "peerDependencies": {
+    "better-sqlite3": ">=9.0.0"
+  },
+  "peerDependenciesMeta": {
+    "better-sqlite3": {
+      "optional": true
+    }
+  },
   "devDependencies": {
     "@arethetypeswrong/cli": "^0.18.2",
     "@eslint/js": "^10.0.1",
     "@google/genai": "^1.46.0",
+    "@types/better-sqlite3": "^7.6.13",
     "@vitest/coverage-v8": "^4.0.18",
+    "better-sqlite3": "^12.8.0",
     "esbuild": "^0.27.3",
     "eslint": "^10.0.2",
     "openai": "^6.25.0",
diff --git a/src/index.ts b/src/index.ts
index 1a75719..daf1a98 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -72,6 +72,10 @@ export { splitSentences, normalizeScores, combineScores } from './entropy.js';
 export { analyzeContradictions } from './contradiction.js';
 export type { ContradictionAnnotation } from './contradiction.js';
 
+// Persistence (optional peer dependency: better-sqlite3)
+export { SqliteStore } from './sqlite-store.js';
+export type { SqliteStoreLoadResult } from './sqlite-store.js';
+
 // Types
 export type {
   Classifier,
diff --git a/src/sqlite-store.ts b/src/sqlite-store.ts
new file mode 100644
index 0000000..724e9e5
--- /dev/null
+++ b/src/sqlite-store.ts
@@ -0,0 +1,172 @@
+import type BetterSqlite3 from 'better-sqlite3';
+import type { CompressResult, Message, VerbatimMap } from './types.js';
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+type DatabaseConstructor = new (path: string, options?: any) => BetterSqlite3.Database;
+
+async function loadBetterSqlite3(): Promise<DatabaseConstructor> {
+  try {
+    const mod = await import('better-sqlite3');
+    return (mod.default ?? mod) as unknown as DatabaseConstructor;
+  } catch {
+    throw new Error(
+      'SqliteStore requires "better-sqlite3" as a peer dependency. ' +
+        'Install it with: npm install better-sqlite3',
+    );
+  }
+}
+
+const SCHEMA = `
+  CREATE TABLE IF NOT EXISTS conversations (
+    conversation_id TEXT NOT NULL,
+    message_index   INTEGER NOT NULL,
+    message_json    TEXT NOT NULL,
+    PRIMARY KEY (conversation_id, message_index)
+  );
+
+  CREATE TABLE IF NOT EXISTS verbatim (
+    conversation_id TEXT NOT NULL,
+    message_id      TEXT NOT NULL,
+    message_json    TEXT NOT NULL,
+    PRIMARY KEY (conversation_id, message_id)
+  );
+`;
+
+export interface SqliteStoreLoadResult {
+  messages: Message[];
+  verbatim: VerbatimMap;
+}
+
+/**
+ * Persistent verbatim store backed by SQLite via better-sqlite3.
+ *
+ * Provides atomic save/load of CompressResult data (messages + verbatim)
+ * and a StoreLookup function for use with uncompress().
+ *
+ * Requires `better-sqlite3` as an optional peer dependency.
+ *
+ * ```ts
+ * const store = await SqliteStore.open(':memory:');
+ * store.save('conv-1', compressResult);
+ * const data = store.load('conv-1');
+ * const restored = uncompress(data.messages, store.lookup('conv-1'));
+ * store.close();
+ * ```
+ */
+export class SqliteStore {
+  private db: BetterSqlite3.Database;
+
+  private constructor(db: BetterSqlite3.Database) {
+    this.db = db;
+    db.exec(SCHEMA);
+  }
+
+  /**
+   * Open a SQLite store at the given path. Use `:memory:` for an in-memory database.
+   */
+  static async open(path: string): Promise<SqliteStore> {
+    const Database = await loadBetterSqlite3();
+    const db = new Database(path);
+    db.pragma('journal_mode = WAL');
+    return new SqliteStore(db);
+  }
+
+  /**
+   * Atomically save compressed messages and their verbatim originals.
+   *
+   * Messages are replaced entirely for the conversation. Verbatim entries
+   * are upserted — older entries from prior compression rounds are preserved
+   * so that recursive uncompress() works across multiple rounds.
+   */
+  save(conversationId: string, result: CompressResult): void {
+    const insertMsg = this.db.prepare(
+      'INSERT INTO conversations (conversation_id, message_index, message_json) VALUES (?, ?, ?)',
+    );
+    const upsertVerbatim = this.db.prepare(
+      'INSERT OR REPLACE INTO verbatim (conversation_id, message_id, message_json) VALUES (?, ?, ?)',
+    );
+    const deleteMessages = this.db.prepare('DELETE FROM conversations WHERE conversation_id = ?');
+
+    this.db.transaction(() => {
+      deleteMessages.run(conversationId);
+
+      for (let i = 0; i < result.messages.length; i++) {
+        insertMsg.run(conversationId, i, JSON.stringify(result.messages[i]));
+      }
+
+      for (const [id, msg] of Object.entries(result.verbatim)) {
+        upsertVerbatim.run(conversationId, id, JSON.stringify(msg));
+      }
+    })();
+  }
+
+  /**
+   * Load compressed messages and the full verbatim map for a conversation.
+   * Returns null if the conversation does not exist.
+   */
+  load(conversationId: string): SqliteStoreLoadResult | null {
+    const rows = this.db
+      .prepare(
+        'SELECT message_json FROM conversations WHERE conversation_id = ? ORDER BY message_index',
+      )
+      .all(conversationId) as Array<{ message_json: string }>;
+
+    if (rows.length === 0) return null;
+
+    const messages: Message[] = rows.map((r) => JSON.parse(r.message_json) as Message);
+
+    const verbatimRows = this.db
+      .prepare('SELECT message_id, message_json FROM verbatim WHERE conversation_id = ?')
+      .all(conversationId) as Array<{ message_id: string; message_json: string }>;
+
+    const verbatim: VerbatimMap = {};
+    for (const r of verbatimRows) {
+      verbatim[r.message_id] = JSON.parse(r.message_json) as Message;
+    }
+
+    return { messages, verbatim };
+  }
+
+  /**
+   * Return a StoreLookup function for use with uncompress().
+   *
+   * Each call executes a single-row SELECT — no need to load the
+   * entire verbatim map into memory.
+   */
+  lookup(conversationId: string): (id: string) => Message | undefined {
+    const stmt = this.db.prepare(
+      'SELECT message_json FROM verbatim WHERE conversation_id = ? AND message_id = ?',
+    );
+    return (id: string): Message | undefined => {
+      const row = stmt.get(conversationId, id) as { message_json: string } | undefined;
+      return row ? (JSON.parse(row.message_json) as Message) : undefined;
+    };
+  }
+
+  /**
+   * Delete a conversation and all its verbatim entries.
+   */
+  delete(conversationId: string): void {
+    this.db.transaction(() => {
+      this.db.prepare('DELETE FROM conversations WHERE conversation_id = ?').run(conversationId);
+      this.db.prepare('DELETE FROM verbatim WHERE conversation_id = ?').run(conversationId);
+    })();
+  }
+
+  /**
+   * List all stored conversation IDs.
+   */
+  list(): string[] {
+    const rows = this.db
+      .prepare('SELECT DISTINCT conversation_id FROM conversations ORDER BY conversation_id')
+      .all() as Array<{ conversation_id: string }>;
+    return rows.map((r) => r.conversation_id);
+  }
+
+  /**
+   * Close the database connection.
+   */
+  close(): void {
+    this.db.close();
+  }
+}
diff --git a/tests/sqlite-store.test.ts b/tests/sqlite-store.test.ts
new file mode 100644
index 0000000..a305b83
--- /dev/null
+++ b/tests/sqlite-store.test.ts
@@ -0,0 +1,225 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { SqliteStore } from '../src/sqlite-store.js';
+import { compress } from '../src/compress.js';
+import { uncompress } from '../src/expand.js';
+import type { Message } from '../src/types.js';
+
+function msg(id: string, index: number, role: string, content: string): Message {
+  return { id, index, role, content, metadata: {} };
+}
+
+function makeMessages(): Message[] {
+  return [
+    msg('1', 0, 'system', 'You are a helpful assistant.'),
+    msg('2', 1, 'user', 'Explain how caching works in distributed systems.'),
+    msg(
+      '3',
+      2,
+      'assistant',
+      'Caching in distributed systems involves storing frequently accessed data in a fast storage layer. ' +
+        'The cache invalidation strategy determines when stale entries are removed. ' +
+        'Common approaches include TTL-based expiration, write-through caching, and cache-aside patterns. ' +
+        'Each approach has different trade-offs for consistency, latency, and complexity. '.repeat(
+          3,
+        ),
+    ),
+    msg('4', 3, 'user', 'What about Redis specifically?'),
+    msg(
+      '5',
+      4,
+      'assistant',
+      'Redis is an in-memory data structure store that supports multiple data types including strings, hashes, lists, and sorted sets. ' +
+        'It provides built-in replication, Lua scripting, LRU eviction, and persistence options. '.repeat(
+          3,
+        ),
+    ),
+  ];
+}
+
+describe('SqliteStore', () => {
+  let store: SqliteStore;
+
+  beforeEach(async () => {
+    store = await SqliteStore.open(':memory:');
+  });
+
+  afterEach(() => {
+    try {
+      store.close();
+    } catch {
+      // already closed
+    }
+  });
+
+  it('opens an in-memory database', async () => {
+    const s = await SqliteStore.open(':memory:');
+    expect(s).toBeInstanceOf(SqliteStore);
+    s.close();
+  });
+
+  it('save and load roundtrip', () => {
+    const messages = makeMessages();
+    const result = compress(messages, { recencyWindow: 0 });
+
+    store.save('conv-1', result);
+    const loaded = store.load('conv-1');
+
+    expect(loaded).not.toBeNull();
+    expect(loaded!.messages).toEqual(result.messages);
+    expect(loaded!.verbatim).toEqual(result.verbatim);
+  });
+
+  it('load returns null for nonexistent conversation', () => {
+    expect(store.load('nonexistent')).toBeNull();
+  });
+
+  it('save replaces messages but accumulates verbatim', () => {
+    const messages = makeMessages();
+    const result1 = compress(messages, { recencyWindow: 0 });
+    store.save('conv-1', result1);
+
+    const verbatimCount1 = Object.keys(result1.verbatim).length;
+
+    // Second compression with different messages
+    const messages2 = [
+      msg(
+        '10',
+        0,
+        'user',
+        'New conversation content about deployment pipelines and CI/CD. '.repeat(5),
+      ),
+      msg(
+        '11',
+        1,
+        'assistant',
+        'Deployment pipelines automate the build, test, and release process. '.repeat(5),
+      ),
+    ];
+    const result2 = compress(messages2, { recencyWindow: 0 });
+    store.save('conv-1', result2);
+
+    const loaded = store.load('conv-1');
+    expect(loaded).not.toBeNull();
+
+    // Messages should be from the second save only
+    expect(loaded!.messages).toEqual(result2.messages);
+
+    // Verbatim should contain entries from both rounds
+    const totalVerbatim = Object.keys(loaded!.verbatim).length;
+    const verbatimCount2 = Object.keys(result2.verbatim).length;
+    expect(totalVerbatim).toBe(verbatimCount1 + verbatimCount2);
+  });
+
+  it('lookup returns a working StoreLookup function for uncompress', () => {
+    const messages = makeMessages();
+    const result = compress(messages, { recencyWindow: 0 });
+    store.save('conv-1', result);
+
+    const lookupFn = store.lookup('conv-1');
+    const expanded = uncompress(result.messages, lookupFn);
+
+    expect(expanded.missing_ids).toEqual([]);
+    expect(expanded.messages).toEqual(messages);
+  });
+
+  it('lookup returns undefined for missing IDs', () => {
+    const lookupFn = store.lookup('conv-1');
+    expect(lookupFn('nonexistent-id')).toBeUndefined();
+  });
+
+  it('delete removes conversation', () => {
+    const messages = makeMessages();
+    const result = compress(messages, { recencyWindow: 0 });
+    store.save('conv-1', result);
+
+    store.delete('conv-1');
+    expect(store.load('conv-1')).toBeNull();
+
+    // Verbatim should also be gone
+    const lookupFn = store.lookup('conv-1');
+    for (const id of Object.keys(result.verbatim)) {
+      expect(lookupFn(id)).toBeUndefined();
+    }
+  });
+
+  it('multiple conversations are isolated', () => {
+    const messages = makeMessages();
+    const result = compress(messages, { recencyWindow: 0 });
+    store.save('conv-a', result);
+
+    const other = [msg('20', 0, 'user', 'Different conversation entirely.')];
+    const result2 = compress(other, { recencyWindow: 0 });
+    store.save('conv-b', result2);
+
+    const loadedA = store.load('conv-a');
+    const loadedB = store.load('conv-b');
+
+    expect(loadedA!.messages).toEqual(result.messages);
+    expect(loadedB!.messages).toEqual(result2.messages);
+    expect(Object.keys(loadedA!.verbatim).length).toBe(Object.keys(result.verbatim).length);
+  });
+
+  it('list returns stored conversation IDs', () => {
+    const messages = makeMessages();
+    const result = compress(messages, { recencyWindow: 0 });
+    store.save('conv-b', result);
+    store.save('conv-a', result);
+
+    const ids = store.list();
+    expect(ids).toEqual(['conv-a', 'conv-b']);
+  });
+
+  it('list returns empty array when no conversations stored', () => {
+    expect(store.list()).toEqual([]);
+  });
+
+  it('messages with extra fields survive serialization', () => {
+    const messages: Message[] = [
+      {
+        id: '1',
+        index: 0,
+        role: 'assistant',
+        content: 'Test content that is long enough to trigger compression in the pipeline. '.repeat(
+          5,
+        ),
+        metadata: { custom: 'value' },
+        tool_calls: [{ id: 'tc1', function: { name: 'test', arguments: '{}' } }],
+        customField: 42,
+      },
+    ];
+    const result = compress(messages, { recencyWindow: 0 });
+    store.save('conv-1', result);
+
+    const loaded = store.load('conv-1');
+    expect(loaded).not.toBeNull();
+
+    // The messages array from compress might have modified the content,
+    // but all fields present in the result should survive the roundtrip
+    expect(loaded!.messages).toEqual(result.messages);
+  });
+
+  it('recursive uncompress works across multiple compression rounds', () => {
+    const messages = makeMessages();
+
+    // Round 1: compress
+    const round1 = compress(messages, { recencyWindow: 0 });
+    store.save('conv-1', round1);
+
+    // Round 2: compress the already-compressed messages again
+    const round2 = compress(round1.messages, { recencyWindow: 0 });
+    store.save('conv-1', round2);
+
+    // Recursive uncompress should restore originals through the chain
+    const lookupFn = store.lookup('conv-1');
+    const expanded = uncompress(round2.messages, lookupFn, { recursive: true });
+
+    // Should have no missing IDs — both rounds' verbatim entries are in the store
+    expect(expanded.missing_ids).toEqual([]);
+    expect(expanded.messages).toEqual(messages);
+  });
+
+  it('close prevents subsequent operations', () => {
+    store.close();
+    expect(() => store.list()).toThrow();
+  });
+});