Addon Development

Addon Development

Auto Storage exposes a bounded NeoForge addon SDK for deterministic stations, recipes, typed resources, transfers, transforms, and station variants. Addons use the same public registries as Auto Storage's bundled compatibility modules. Storage, planning, validation, and mutation remain server-authoritative.

This document is the authoritative addon guide. The GitHub Wiki copy must match it at every SDK release; edit this file first. The Wiki page is intentionally not listed in the player-manual Home contents or sidebar.

Start with Compat Kit

Use the Auto Storage Compat Kit before writing a bundled integration or independent addon. It scans one reproducible target jar/source revision, creates an explicit reviewed recipe contract, generates either a deliberately RED SDK-only scaffold or reviewed mechanical registration, and runs the contract's verification gates. It does not infer consumption, catalysts, outputs, units, station costs, or determinism. Every scaffold/verify command also loads the committed source audit. The exact audited recipe-candidate set, target identity, artifact SHA, and inventory digest must match the contract, so recomputing a contract-only field cannot hide an omitted candidate. Candidate records must also remain in the bucket computed by the current scanner; changing a recipe into a station/resource record is rejected. When source is supplied, at least one classified candidate must map to a tracked, non-ignored Java file in that Git module; ignored build output or an unrelated clean checkout cannot contribute its revision as target evidence. Candidate-source suffixes match only at path-segment boundaries, and risk evidence must remain owned by an audited recipe candidate. The scanner also rehashes the target after inspection, so an atomically replaced jar cannot mix two artifacts in one audit.

tools/compat-kit/compat-kit scan --help
tools/compat-kit/compat-kit decide --help
tools/compat-kit/compat-kit migrate-contract --help
tools/compat-kit/compat-kit validate-probe --help
tools/compat-kit/compat-kit generate --help
tools/compat-kit/compat-kit conformance --help
tools/compat-kit/compat-kit resource-scaffold --help
tools/compat-kit/compat-kit scaffold --help
tools/compat-kit/compat-kit verify --help

generate accepts only a completed contract plus a reviewed plan bound to its exact digest. It emits direct typed station/family registration for bounded safe shapes and rate bindings; a handwritten provider still owns exact typed selection, catalysts/tools/remainders, and costs. Unsupported semantics remain an explicit RED boundary. Dynamic rate accessors are reviewed as integral and converted exactly; families sharing a descriptor must share the same reviewed definition. Each generated family also declares its runtime registration_id; the audit family key is evidence identity and is not assumed to be a registry path. Family-derived Java names use a collision-free family$ prefix for digit-leading or reserved IDs and shared identifier validation. conformance requires a batch of at least 2, rejects happy-delta × batch signed-long overflow, and generates repeated snapshot/delta/rollback assertions around addon-supplied operations rather than trusting booleans returned by the addon. resource-scaffold generates only public-API custom-resource boundaries, sample-keyed persistence/transfer assertions, and rejects built-in Item, Fluid, and NeoForge Energy support. Valid digit-leading resource IDs are normalized through one collision-checked Java-name derivation that prefixes _ where required. None of these commands add runtime reflection or make the client authoritative. Repository tests regenerate and compile the committed generated-scaffold fixture against the public API jar.

Supply the target's complete non-JDK compile ancestry through repeatable --classpath for scan and every complete consumer; every unresolved external superclass or interface fails instead of silently hiding a structural recipe family, including classes whose names look like client viewers, builders, or datagen helpers. The audit records only exact classpath artifact SHA/size evidence, and each ancestry jar is rehashed after all inherited-bytecode inspection so an in-flight replacement fails. A structurally discovered recipe inspects implementation classes along its target/classpath hierarchy and attributes compact inherited risks to the concrete recipe. Completed contracts separately bind the recipe-class inventory and effective recipe-data/data-pack digest. Runtime probe JSON must pass validate-probe with the same audit and optional plan; schema validation alone does not prove those cross-file identities. Every complete generation, conformance, resource, scaffold, and verification command also receives the exact target jar. Compat Kit rehashes it and rebuilds the complete sorted class/metadata inventory instead of trusting an edited audit's self-consistent count or digest. It also rebuilds the target jar recipe source count and, when no external data root contributed recipes, requires the entire recorded recipe inventory to match those jar bytes. Generated addon CI uses stageCompatKitTargetArtifact plus stageCompatKitAncestryArtifacts, then passes build/compat-kit/target.jar to verify --jar and every staged ancestry jar through repeatable --classpath. The generated ancestry task searches the target's transitive dependency graph and NeoForge's additional runtime classpath, then stages only SHA/size matches from the audit. If the target publishes optional compile APIs non-transitively, the task fails with their missing SHA values; add those reviewed coordinates to compatKitAncestryArtifacts rather than weakening or removing the exact gate. Complete consumers reopen every supplied ancestry jar and reconstruct the reachable external metadata graph, so editing classpath-owned graph records cannot remove structural recipe candidates while preserving a self-consistent JSON audit.

The scanner first verifies that resolved javap belongs to a JDK whose release metadata and actual javap -version both report major version 21, then accepts platform ancestry only when the class is present in that JDK's module inventory. Package prefixes such as javax.* do not bypass missing classpath evidence. It uses class-file SourceFile, InnerClasses, and EnclosingMethod metadata for source ownership and nested classes. Thus a top-level or named class whose identifier contains $ remains auditable while local, anonymous, and synthetic classes stay excluded. When SourceFile is absent, a supplied source checkout fails as unavailable rather than guessing a same-named compilation unit. Format 15 stores binary and source-level Java names, each candidate's structural classification, a separate sorted top-level structural_hierarchy inventory, an artifact/classpath-bound structural candidate digest, and direct metadata for every target class plus reachable ancestry. The artifact also binds the complete target-class count and graph digest. Validation independently reconstructs each candidate from that graph, so removing both derived indirect-path copies cannot bypass review. Generated Java uses the source-level name for nested classes and preserves legal top-level $ identifiers. Direct public extends/implements declarations provide a second bucket cross-check; generic type bounds do not count as direct ancestry. Legacy formats 7 through 14 must be rescanned with migrate-audit. A class name that normalizes to no alphanumeric family ID uses deterministic class_<binary-name-hex> evidence. Explicit --data-root evidence binds all bounded tag JSON and bounded pack.mcmeta bytes while keeping recipe counts recipe-only; a root with a top-level data-pack filter or overlays field is rejected rather than misreporting filtered or overlay recipes as effective. Any ancestry artifact SHA/size change affects diff and reopens migrated family decisions even when target public signatures are stable. Each ancestry class must have exactly one jar owner. The scanner rejects duplicate definitions even when their hierarchy declarations match, validates JDK 21 before a cache hit, and invalidates the cache when the selected JDK module identity changes. Recipe risks traverse the complete non-JDK superclass and interface graph, not only the hierarchy path that established Recipe classification.

Complete contracts use lowercase resource locations for recipe types, station descriptor IDs, and station variant items. Generated rate bindings are one-to-one with those station items; duplicate descriptor variants and duplicate rate bindings are rejected. registry_block_method bindings name their block ID separately from the representative station item. The generated single_item_to_item path accepts only the documented one-input/one-primary output selectors and exact amount expressions, and method bindings reject Java keywords; all other shapes need a reviewed provider. Generated custom-resource tests verify that their sample key and amount were seeded, that clear() removes that key, and that load() restores the exact snapshot before exercising the remaining persistence boundaries. worker-package runs every declared Gradle task without replacing the worker's JDK environment, so the target's authoritative GameTest remains part of a delegated worker gate. Worker instructions identify targets only by validated mod ID; free-form display metadata is retained as escaped, explicitly untrusted JSON evidence.

Add the SDK

Every GitHub release contains:

• auto_storage-<version>.jar — the player/runtime mod;
• auto_storage-<version>-api.jar — the compile-only SDK;
• auto_storage-<version>-api-sources.jar;
• auto_storage-<version>-api-javadoc.jar.

The public GitHub release can be consumed without copying a jar into libs/:

def autoStorageVersion = "0.3.0"

repositories {
    ivy {
        name = "AutoStorageReleases"
        url = uri(
                "https://github.com/swear01/Auto_Storage/releases/download/"
                        + "v${autoStorageVersion}")
        patternLayout {
            artifact("[artifact]-[revision](-[classifier]).[ext]")
        }
        metadataSources {
            artifact()
        }
    }
}

dependencies {
    compileOnly(
            "com.swear.autostorage:auto_storage:${autoStorageVersion}:api")
    runtimeOnly(
            "com.swear.autostorage:auto_storage:${autoStorageVersion}")
}

Use normal NeoForge dependency metadata to require Auto Storage. If the addon integrates another mod, declare that target dependency in the addon's own metadata as well. Do not pin player installations to Auto Storage's representative CI fixture versions.

Compat Kit contracts list every target Maven repository as an explicit HTTPS URL. The generated addon copies those repositories into build.gradle; it does not infer Modrinth, Curse Maven, or an upstream repository from a dependency coordinate. Keep this list minimal, ordered, and reviewable; declaration order is preserved because it can change which repository serves a coordinate. Reviewed repositories are emitted before defaults and restricted to target/runtime groups. Explicit runtime groups cannot fall back to Maven Central even when the reviewed repository list is empty; the target can fall back only under its exact SHA check. Fixed repository filters reserve Patchouli and Auto Storage for BlameJared and the release Ivy repository. The generated build also copies every explicit target.runtime_dependencies entry, so required libraries such as GuideME do not depend on transitive metadata or an undocumented post-scaffold edit. Target and explicit runtime dependencies are non-transitive on both target compile and runtime classpaths, so every required companion must be listed. The generated build resolves the reviewed target dependency separately and checks its exact jar SHA against source_audit_sha256 during both build and runGameTestServer; it also copies the reviewed audit to compat/audit.json. Reviewed repository URLs, dependency coordinates, and group filters are serialized as literal Groovy strings rather than interpolated text. Maven coordinates must use exact group:name:version structure and cannot contain control characters. Because Auto Storage requires Patchouli on both sides, the generated GameTest runtime includes the matching Patchouli artifact and its repository. A different target artifact or source audit fails before compatibility evidence can pass. Verification regenerates the expected build.gradle, settings.gradle, gradle.properties, gradlew, gradlew.bat, and Gradle wrapper jar/properties from the reviewed contract and generator before comparing each with both the file and manifest. An addon therefore cannot replace the launcher or artifact gate and authorize that edit by updating its own manifest hash. Scaffold generation preflights all destinations and parent directories before its first write. Existing conflicting files, symlinked roots/ancestors/targets, or a file-valued src ancestor fail without leaving workflow, manifest, wrapper fragments, or writes outside the output root. This includes existing symlink ancestors above a not-yet-created output root, and lexical .. segments are normalized before that preflight. Byte-identical reruns repair both generated launchers to mode 0755.

An independent-addon contract uses fixture main, declares exactly build and runGameTestServer, and maps every evidence record to one of those actual tasks. Published completed-contract schemas require that non-null fixture, GameTest count in 1..2147483647, authoritative task, nonempty task list, all twelve exact checks, and every evidence mapping; unresolved RED drafts may keep those fields empty. A runGameTestServer evidence marker must live inside the annotated GameTest method that executes the assertion; file-level constants, comments, and detached helpers are rejected. Runtime probes require an explicit --game-test-namespace; conformance and resource plans require the same exact game_test_namespace, and every generated class emits it in @GameTestHolder. An addon's holder must resolve to the addon's enabled <target_mod_id>_auto_storage namespace; a test compiled in another namespace is not evidence. Referenced holder constants are resolved by their actual declaring class, not the source file stem. Comments inside the method do not count, while executable string arguments may carry assertion markers. Eligible Java Unicode escapes are rejected before evidence parsing so they cannot create comments or method boundaries before tokenization. Its fresh-world cleanup rejects a symlinked lexical addon root, every ancestor of that root, run, or world, plus resolved paths outside the addon root before deletion. Bundled task names are not translated or treated as equivalent. GameTest output must contain exactly one success summary with the reviewed count; conflicting summaries fail even when one count matches. A published passing report must carry the strict target identity, all twelve mandated check records, and exactly the addon build and runGameTestServer command records. Commented or string-literal @GameTest text is ignored by both source counting and method-body evidence extraction; intermediate annotation initializers are skipped until the real method body, escaped triple quotes stay inside Java text blocks, and every GameTest evidence file must belong to the fixture source set executed by its declared task.

Register through one facade

Create addon-owned DeferredRegister instances with the focused API classes, then wire all of them to the addon's mod event bus in one call:

public ExampleAddon(IEventBus modBus) {
    AutoStorageAddon.register(MOD_ID, modBus, addon -> addon
            .machineDescriptors(MACHINES)
            .recipeFamilies(RECIPES)
            .resourceKinds(RESOURCE_KINDS)
            .containerStrategies(CONTAINERS)
            .blockStrategies(BLOCKS)
            .transformProviders(TRANSFORMS)
            .machineVariantContributors(VARIANTS));
}

The complete compilable example is examples/addon/src/main/java/example/autostorage/ExampleAddon.java. ./gradlew compileAddonExampleJava compiles it against only the generated API jar and NeoForge/Minecraft dependencies, not Auto Storage's implementation output.

The facade verifies:

• every register targets the expected Auto Storage custom registry;
• every DeferredRegister uses the addon's namespace;
• the same register is not wired twice;
• at least one Auto Storage registry is contributed;
• reload-hook IDs belong to the addon namespace.

Registry entries and reload hooks are registration-time contracts. Runtime hot registration is unsupported. Call the facade from the addon's mod constructor: Auto Storage closes the registration window at NeoForge's first registry event, and a later call fails immediately instead of attaching listeners that can no longer run.

Extension points

Stations

Use MachineDescriptorApi.createDeferredRegister(MOD_ID) and register one stable descriptor per logical station family. A descriptor can represent one station item or multiple exact variants with different rational work rates. Choose MachineCategory.PROCESS, INSTANT, or TRANSFORM; addon code does not depend on the internal MachineEnergyTable. See Machine Descriptor API.

Deterministic recipe families

Use RecipeFamilyApi.createDeferredRegister(MOD_ID). One entry covers one exact recipe class plus exact RecipeType, not individual recipe IDs.

• singleItemToItem covers one consumed item and one deterministic item output.
• deterministicResources covers bounded exact item/fluid/energy/chemical/addon inputs, catalysts, tools, remainders, multiple outputs, and station costs.
• deterministicResourceVariants covers a bounded set of complete deterministic plans selected from exact available stacks.

See Recipe Family API.

Typed resources

Register a StorageResourceKind for a stable kind ID. Add StorageResourceContainerStrategy entries for item-container deposit/withdraw and StorageResourceBlockStrategy entries for sided world capabilities. Multi-key Core mutation uses one StorageResourceTransaction.

If the registered representative item is not enough to render an exact resource variant, register a client-only icon renderer during client setup:

TerminalResourceRendererApi.register(
        MY_RESOURCE_KIND,
        GuiGraphics.class,
        (graphics, key, amount, x, y, partialTick) -> {
            renderExactResource(graphics, key, amount, x, y, partialTick);
            return true;
        });

The generic context keeps auto_storage-<version>-api.jar free of net.minecraft.client bytecode references while still giving client modules a typed GuiGraphics lambda. Never call this hook from common or dedicated-server initialization. IDs are bounded and unique; duplicate renderers fail explicitly. Client renderer registration closes before menu screens are registered; later calls fail instead of mutating a live terminal. Returning false asks the terminal to render the resource kind's registered representative item instead.

See Typed Resource Storage.

Transform providers

Create a DeferredRegister<TransformProvider> through TransformProviderApi.createDeferredRegister(MOD_ID). Each provider resolves one exact inserted item into a positive typed output and, optionally, a matching station-work cost. Resolvers must be deterministic and side-effect free.

Auto mode only discovers matching uses. The server revalidates the exact input, selected provider, output capacity, and station work before one simulate-then-commit mutation.

Existing-station variants

Create a DeferredRegister<MachineVariantContributor> through MachineVariantContributorApi.createDeferredRegister(MOD_ID). A contribution adds exact station items and rates to an existing logical descriptor without replacing its ID or recipe family. The target descriptor must exist when Auto Storage materializes the registry snapshot. A misspelled or removed target fails with both the contribution ID and descriptor ID instead of being ignored.

Capabilities and recipe reload data

The facade also exposes the two bounded lifecycle hooks required by current integrations:

private static final BlockCapability<MyResourceView, Direction> CAPABILITY =
        BlockCapability.createSided(id("resource_view"), MyResourceView.class);

AutoStorageAddon.register(MOD_ID, modBus, addon -> addon
        .resourceKinds(RESOURCE_KINDS)
        .capabilities(event ->
                AutoStorageCapabilityApi.registerSidedResourceCapability(
                        event,
                        CAPABILITY,
                        (resources, side) -> new MyResourceView(resources)))
        .recipeReload(id("runtime_recipes"), MyRecipes::refresh));

capabilities receives NeoForge's RegisterCapabilitiesEvent. AutoStorageCapabilityApi.registerSidedResourceCapability(...) exposes only a server-owned StorageResourceHandler for the Core, Import Bus, and Export Bus; it does not expose their implementation block entities. The returned wrapper must obey the same simulation, exact accepted-amount, and side rules as every other typed-resource handler. recipeReload runs at server start and after a global datapack reload. Hooks run in stable ID order and freeze before gameplay; duplicate, foreign, or late hooks fail explicitly. Auto Storage runs every hook before invalidating and rebuilding the shared Craftable catalog, so one reload cannot retain a pre-hook cache. Arbitrary tick, player, world, or mutation callbacks are not part of the SDK.

Failure and safety contract

Addon code must provide complete deterministic contracts. Auto Storage does not infer recipes through reflection, generic Recipe#getIngredients(), EMI widgets, serializer names, or machine names. It does not send resources into an external machine and wait for world state.

The reviewed contract must preserve every scanner risk attached to each recipe family. Process station variants use positive work rates; Instant variants use zero rates. Accepted families keep an explicit costs list, which may be empty only for a reviewed runtime family that is genuinely free. A bundled contract's GameTest task must be the task derived from its fixture name; another fixture with the same expected count cannot provide its runtime evidence. Compat Kit rejects drift before generating code that runtime descriptor validation would reject.

Registration, linkage, or validation failures are startup errors. Auto Storage does not silently skip a loaded but incompatible integration. Runtime crafting uses current server recipe holders, checked long arithmetic, joint reservation, capacity planning, and one atomic storage transaction. Client UI and EMI are presentation/input surfaces only.

Bundled compatibility modules

The player still installs one Auto Storage jar. Bundled integrations live in isolated src/compat/<mod-id> source sets. Each module owns one src/compat/<mod-id>/compat-module.json descriptor containing its entrypoint, required mods, source-set/fixture names, and representative compile dependencies. Gradle validates every descriptor and deterministically generates the runtime index. Descriptor expectedTests is a positive JSON integer; fractional or wider numeric values fail instead of being truncated. The generated META-INF/auto_storage/compat-modules.json has no second hand-written central module list. The loader checks every required mod ID before resolving the module class. A present module uses AutoStorageCompatModule plus the same registration facade available to external addons. Every bundled entry must declare at least one required target mod; an empty requirement list is rejected before classloading. Compat Kit descriptors also carry the reviewed target repositories and artifact SHA, so a non-central Maven target resolves through contract-owned configuration rather than a root-build guess. Compat Kit rejects target IDs that would become Java reserved package segments instead of emitting uncompilable source. Before scaffold writes, the generated module ID, entrypoint, source set, and fixture are compared with all existing descriptors so normalized Java/Gradle identifier collisions fail closed.

External addons do not add entries to Auto Storage's bundled module index. They are ordinary NeoForge mods with their own entrypoint and dependency metadata.

API stability

The API artifact version equals the Auto Storage mod version.

• Before Auto Storage 1.0, the SDK is alpha. Breaking API changes require a minor-version increase and release-note migration section.
• Patch releases must remain source- and binary-compatible with the preceding release in the same minor line.
• Compat Kit therefore generates a current-minor dependency range; version 0.3.0 produces [0.3.0,0.4), not an open-ended pre-1.0 range.
• Compat Kit publication receives the authoritative Gradle mod_version and fails if it differs from the tool version. Its addon example and ten machine-readable schemas use explicit tracked allowlists, never recursive or globbed local-output scans.
• Registry IDs and persisted resource/descriptor IDs are data contracts and must not be reused for different semantics.
• Optional target-mod versions in CI are representative evidence only. Addons should declare semantic ranges they actually support and report incompatible target changes clearly.

CI compiles a different-package fixture and the example against only the classified API jar, compares its public javap output with api/api-surface.txt, scans API bytecode for client/optional-mod links, builds each bundled module against the API jar plus only its target dependencies, and runs isolated plus all-mod GameTest gates. Any intentional API change must review and update that snapshot in the same change.