Canonical: https://rom-weaver.com/docs/cheat-database # Cheat database reference ## Table of contents - [Supported systems](<#supported-systems>) - [Delivery classes](<#delivery-classes>) - [Match classes](<#match-classes>) - [Data source](<#data-source>) - [CLI database directory](<#cli-database-directory>) - [Storage and network behavior](<#storage-and-network-behavior>) - [Shard file](<#shard-file>) - [Preserved source fields](<#preserved-source-fields>) - [Bundles](<#bundles>) ## Supported systems | Database system | Rust decoders | | --- | --- | | Nintendo Entertainment System | Game Genie, Pro Action Replay | | Super Nintendo Entertainment System | Game Genie, Pro Action Replay | | Sega Genesis / Mega Drive | Game Genie, Pro Action Replay | | Sega 32X | Game Genie, Pro Action Replay | | Sega Master System | Game Genie, Pro Action Replay | | Sega Game Gear | Game Genie, Pro Action Replay | | Game Boy | Game Genie, GameShark | | Game Boy Color | Game Genie, GameShark | | Game Boy Advance | Xploder ROM-patch codes | rom-weaver does not offer database systems outside this table. ## Delivery classes | Class | Meaning | Output | | --- | --- | --- | | ROM cheat | Every subcode decodes to a cartridge ROM address | Ordered ROM write step | | Unsupported | The code cannot bake into the ROM | Disabled, with a reason | An unsupported row shows its reason and cannot be selected. Reasons include: the code targets runtime memory, some of its linked subcodes target runtime memory, the entry needs a parameter value, or the entry is a structured RetroArch memory entry rather than a native code. ## Match classes | Match | Meaning | | --- | --- | | Exact | A known checksum matched a canonical release record and its cheat set. | | Title | A normalized title matched, but the ROM checksum did not match. | | Manual | The user selected a game record. | | None | rom-weaver found no automatic game match. | Title and manual matches can target another region or revision. ## Data source The shards derive from the `cht/` directories of `libretro/libretro-database` at the same pinned revision as the identify packs. The identify index (`index.json`, `sources.libretro.revision`) records that revision, and the Cheats section shows it. Source [libretro/libretro-database]() License CC-BY-SA-4.0 The generated shards are an adapted database under CC-BY-SA-4.0. rom-weaver's code license does not replace that data license. ShareAlike applies to redistributed adaptations of this database. The distribution includes the full license text and the source revision in the third-party notices. Game titles and release checksums come from the same Libretro DAT files that build the platform's identify pack, so a cheat match and an identify match agree on the ROM. Before packaging, the build removes structured RetroArch entries, empty or placeholder codes, and entries whose every subcode has a known runtime-memory address. Mixed entries remain for the ROM-dependent decoder to classify; an entry remains unsupported if any subcode cannot bake. ## CLI database directory The CLI reads the same shards the webapp serves, from a directory on disk. | Path | Contents | | --- | --- | | `nintendo-nintendo-entertainment-system.json.br` | Nintendo Entertainment System shard. | | `nintendo-super-nintendo-entertainment-system.json.br` | Super Nintendo Entertainment System shard. | | `sega-mega-drive-genesis.json.br` | Sega Genesis / Mega Drive shard. | | `sega-master-system-mark-iii.json.br` | Sega Master System shard. | | `sega-game-gear.json.br` | Sega Game Gear shard. | | `sega-32x.json.br` | Sega 32X shard. | | `nintendo-game-boy.json.br` | Game Boy shard. | | `nintendo-game-boy-color.json.br` | Game Boy Color shard. | | `nintendo-game-boy-advance.json.br` | Game Boy Advance shard. | | `manifest.json` | Source name, source revision, source URL, and license. Optional. | Each shard may also be a plain `.json`, or carry the `cheats-` prefix the repository's own data directory uses. When several forms are present the CLI reads the `.json.br` copy. The directory comes from `--cheat-database DIR`, then `$ROM_WEAVER_CHEAT_DATABASE`, then `cheats` inside the [identify database directory](). `ROM_WEAVER_DATA_DIR` moves the base the same way it moves the identify data. `rom-weaver setup` installs the shards there along with the identify packs; they travel in the same archive. A missing shard is an error naming the file it looked for and the command that installs it. [ROM identify data]() documents how to build the identify packs and cheat shards from their pinned sources. ## Storage and network behavior Each shard is one identify data asset (`assets/identify-cheats-.json`) listed in the identify index with its size and SHA-256. The app loads only the detected or selected platform. A shard belongs to the same pack group as its platform's identify pack. The background warm-up downloads the default group, the Settings page installs optional groups, and the CLI `identify database install-group` installs the same shards natively. An uncached shard is fetched on demand when the Cheats section opens. All nine shards are in the default group. Together they add about 2 MB to the default group download and about 17 MB of decoded JSON to the browser's cache storage. The service worker verifies each shard's SHA-256 before it stores it, and the parsing worker verifies it again before use. A shard that fails either check reports the database as unavailable. A dedicated browser worker parses each shard and restores the fields the file leaves out (see [Shard file](<#shard-file>)). The initial JavaScript bundle does not contain the database. The hosted app requests shards only from its own origin. It makes no runtime request to Libretro. ## Shard file A shard is one JSON document: `schemaVersion`, `system`, `sourceRevision`, and `games`. Each game carries its `id`, `title`, `normalizedTitle`, `regions`, `revisions`, `sourceFiles`, `checksums`, and `cheats`. The file stores each cheat record without the values a reader derives. The CLI and the browser worker restore them the same way: | Record field | Source in the file | | --- | --- | | `system` | the shard's `system` | | `gameId` | the game's `id` | | `sourceRevision` | the shard's `sourceRevision` | | `sourceFile` | `sourceFiles[sourceFile]` of the game (the file stores an index) | | `description` | stored when the source record has a `desc` field, else `Cheat ` | | `rawFields.desc`, `rawFields.code` | `description` and `rawCode` | | `rawFields.enable` | stored only when it is not `false` | | `id` | `cheat_` plus the first 24 hex digits of SHA-256 over `system`, `gameId`, `codeKind`, and the raw fields without `enable`, as key-sorted JSON, joined by NUL bytes | Record IDs do not depend on the file layout, so a bundle written against an earlier layout still names the same records. ## Preserved source fields Each imported record keeps the original code, every `cheatN_*` value, unknown fields, source file, source index, and source revision. A source record without a `cheatN_enable` line reads as `enable = false`. rom-weaver does not synthesize RetroArch memory handlers. It only decodes the native code fields the source record already carries. ## Bundles A bundle's optional top-level `cheats` array records a selection: each entry carries the record `id`, the `source` database and `revision`, the `description`, and a `code` snapshot. `bundle create --cheat` and `patch apply --emit-bundle` write the array. Applying the bundle resolves each entry by `id` against the database at `--cheat-database`, and falls back to its `code` snapshot when the database is absent. An unresolvable entry fails the apply unless it is marked `optional`. For the field list, see [CLI reference](). For the CLI task, see [Bake cheat codes into a ROM](). For the browser task, see [Use cheats in the browser](). For the baking model, see [ROM cheats]().