Kiln

Annotate a data class. Rebuild. Get a complete, type-safe SQLite repository.

No SQL to write. No version numbers to track. No migration files to maintain.

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• Compile-time generation

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  KSP reads your annotations and generates the full repository before your code compiles. Zero runtime reflection, zero overhead.

• Version-less auto-migration

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  Add, rename, or remove a property. Just rebuild — Kiln diffs the live schema and migrates automatically.

• Reactive by default

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  observeAll() and observeWhere() return Flow<List<T>> that re-emits after every write. No polling, no manual refresh.

• Type-safe DSL

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  findWhere { TaskColumns.status eq "DONE" } — queries are compile-time checked with no raw SQL strings.

• Kotlin Multiplatform

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  Define entities in commonMain. Works on Android and iOS from a single source of truth.

• One-line Gradle setup

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  The io.github.sufarook.kiln plugin applies KSP and wires all source sets automatically.

• Relations & transactions

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  @Relation generates typed FK helpers (findByParent, deleteByParent). withTransaction wraps multi-step writes in a single atomic commit.

How it works

// You write this:
@DbEntity(tableName = "tasks")
data class Task(
    @PrimaryKey(autoGenerate = true) val id: Long = 0,
    @Column(name = "project_id", index = true) val projectId: Long,
    val title: String,
    val status: String = "TODO"
)

Kiln generates TaskRepository at compile time with:

Method	Description
createTable()	Creates the table and auto-migrates on every launch
insert(task)	suspend — inserts a row
update(task)	suspend — updates by primary key
delete(id)	suspend — deletes by primary key
findById(id)	suspend — returns Task?
findAll()	suspend — returns List<Task>
findWhere { … }	suspend — type-safe DSL filter
observeAll()	Returns Flow<List<Task>>
observeWhere { … }	Reactive + filtered Flow<List<Task>>
deleteWhere { … }	suspend — bulk delete by predicate
count { … }	suspend — returns Long
insertAll(items)	suspend — bulk insert inside a single transaction
findBy<Parent>(id)	suspend — returns List<T> for a FK parent (requires @Relation)
observeBy<Parent>(id)	Returns Flow<List<T>> filtered by FK parent
deleteBy<Parent>(id)	suspend — deletes all rows belonging to a FK parent

Why Kiln

	Room	SQLDelight	Kiln
SQL you write	@Query annotations	.sq files	None
Migration	Version numbers + SQL files	Manual SQL	Automatic
Reactive Flow	Extra setup	Manual listener	Built-in
Type-safe queries	Partial	Yes	Yes
Kotlin Multiplatform	Android only	Yes	Yes

Quick start

// 1. Apply the plugin in build.gradle.kts
//    id("io.github.sufarook.kiln") version "1.0.0-alpha04"

// 2. Annotate a data class
@DbEntity(tableName = "notes")
data class Note(
    @PrimaryKey(autoGenerate = true) val id: Long = 0,
    val title: String,
    val body: String = ""
)

// 3. Initialize once (e.g. Application.onCreate)
val driver = AndroidDatabaseDriverFactory(context).create("app.db")
val noteRepo = NoteRepository(driver).also { it.createTable() }

// 4. Observe and write
lifecycleScope.launch {
    noteRepo.observeAll().collect { notes -> adapter.submitList(notes) }
}
lifecycleScope.launch {
    noteRepo.insert(Note(title = "First note"))
}

Get started View on GitHub