Distillation

Date: Sep 14, 2026

• 🟡 (09:04) /home/byk/Code/opencode/packages/core/script/migration.ts is a 196-line Bun migration generator/checker using packages/core/schema.json as the Drizzle snapshot, packages/core/src/database/migration for generated TypeScript migrations, packages/core/src/database/migration.gen.ts for the registry, and packages/core/src/database/schema.gen.ts for the full baseline schema.
• 🟡 (09:04) /home/byk/Code/opencode/packages/core/script/migration.ts accepts --check as a boolean and --name as a string. --check runs check() and exits; otherwise it runs generate().
• 🟡 (09:04) generate() creates a temporary opencode-core-migration- directory with incremental and full outputs. For incremental generation it copies schema.json to incremental/baseline/snapshot.json, runs Drizzle with the optional --name, rejects more than one generated migration, writes a new migration to packages/core/src/database/migration/${name}.ts, rejects an already-existing target, and updates packages/core/schema.json from the generated snapshot.
• 🟡 (09:04) After incremental generation, generate() creates a full migration named schema, regenerates /home/byk/Code/opencode/packages/core/src/database/schema.gen.ts from its SQL, and regenerates /home/byk/Code/opencode/packages/core/src/database/migration.gen.ts from sorted *.ts migration names. Its temporary directory is removed recursively with force: true in finally.
• 🟡 (09:04) check() creates a temporary opencode-core-migration-check- workspace and validates three generated artifacts: 1. no incremental migration remains, otherwise "Core schema has ungenerated database migrations. Run \bun script/migration.ts` from packages/core."; 2. schema.gen.tsexactly matches the formatted full-schema rendering, otherwise"Current database schema is stale. Run `bun script/migration.ts` from packages/core."; 3. migration.gen.tsexactly matches the formatted registry, otherwise"Database migration registry is stale. Run `bun script/migration.ts` from packages/core."`.
• 🟡 (09:04) The migration script’s drizzle() writes a temporary config importing packages/core/drizzle.config.ts, overrides out, and runs bun drizzle-kit generate --config ${config} with optional ["--name", name] from the packages/core working directory.
• 🟡 (09:04) generatedMigrations(directory) scans */migration.sql, extracts and sorts directory names; generatedSql(directory) requires exactly one full-schema migration and throws Expected one full schema migration, found ${generated.length}. otherwise; typescriptMigrations() scans *.ts under the migration directory, strips extensions, and sorts names.
• 🟡 (09:04) renderMigration(name, sql) emits an Effect-based default object with id: name and up(tx) satisfying DatabaseMigration.Migration; renderSchema(sql) emits the same shape without id, satisfying Omit<DatabaseMigration.Migration, "id">.
• 🟡 (09:04) renderStatements(sql) splits Drizzle SQL on "--> statement-breakpoint", trims and removes empty statements, then renders each as yield* tx.run(...). Multiline SQL is indented; tabs become two spaces; and escapeTemplate() escapes backslashes, backticks, and ${.
• 🟡 (09:04) formatTypescript(input) dynamically imports Prettier’s TypeScript and Estree plugins and formats with parser: "typescript", semi: false, and printWidth: 120. renderRegistry(names) generates concurrent dynamic imports via Promise.all([...]), maps each module to module.default, and constrains the result with satisfies DatabaseMigration.Migration[].
• 🟡 (09:04) /home/byk/Code/opencode/packages/schema/src/event.ts defines branded event IDs as strings beginning with evt_; Event.ID.create() produces "evt_" + ascending().
• 🟡 (09:04) Event.Definition includes type, a data codec, and optional durable metadata { version: number, aggregate: string }. Event.Payload includes required id, type, and data, plus optional durable payload metadata { aggregateID: string, seq: number, version: number }, optional Location.Ref, and optional Record<string, unknown> metadata.
• 🟡 (09:04) Event.define() builds an Effect Schema struct containing id, optional metadata, a literal type, optional runtime durable fields { aggregateID: Schema.String, seq: Schema.Int, version: Schema.Int }, optional location, and structured data; it annotates the schema with the event type identifier and exposes static type, data, and definition-level durable metadata when supplied.
• 🟡 (09:04) Event.inventory(...definitions) returns a frozen definitions array. Event.latest(definitions) indexes definitions by unversioned event type, selects the greater durable version when both definitions are durable and versions differ, and throws Duplicate latest event definition for ${definition.type} when distinct definitions remain ambiguous.
• 🟡 (09:04) Event.versionedType(type, version) returns ${type}.${version}. Event.durable(definitions) omits nondurable definitions, indexes durable ones by versioned type, and throws Duplicate durable event definition for ${key} for duplicate durable keys.
• 🟡 (09:04) readonlyMap() in /home/byk/Code/opencode/packages/schema/src/event.ts exposes a frozen ReadonlyMap facade implementing size, entries, forEach, get, has, keys, values, and [Symbol.iterator] over a private mutable Map.
• 🟡 (09:04) /home/byk/Code/opencode/packages/schema/src/prompt.ts defines Prompt.Source with finite-number start and end offsets plus required text, annotated as "Prompt.Source".
• 🟡 (09:04) Prompt.FileAttachment has required uri and mime, with optional name, description, and source. FileAttachment.create(input) reconstructs the value through schema.make() while preserving all five fields.
• 🟡 (09:04) Prompt.AgentAttachment contains required name and optional source, annotated as "Prompt.AgentAttachment".
• 🟡 (09:04) Prompt.Prompt contains required text and optional arrays files: FileAttachment[] and agents: AgentAttachment[]. Its statics expose equivalence: Schema.toEquivalence(schema) and fromUserMessage(), which always includes text and conditionally includes files and agents only when they are not undefined.
• 🟡 (09:05) The partially displayed V2 session API schema includes endpoints for listing sessions with cursor/query fields, retrieving active foreground session drains owned by the current OpenCode process, session operations including prompt, compact, idle waiting, reversible boundary staging/moving with optional file application, context retrieval, and durable-event SSE replay/continuation after an aggregate sequence.
• 🟡 (09:05) The displayed V2 session API details include session.compact at POST /api/session/:sessionID/compact, v2.session.context for context retrieval, a boundary payload containing messageID: SessionMessage.ID and optional files: Schema.Boolean, and durable event streaming via HttpApiSchema.StreamSse({ data: SessionEvent.Durable }).