Glossary

Prisma has its own vocabulary, and some of it has shifted with Prisma 7. Use this page to disambiguate terms before reading other pages.

Core concepts

Prisma schema (schema.prisma) — the user-facing schema file written in Prisma Schema Language (PSL). Contains datasource, generator, and model blocks. Parsed by the Wasm PSL parser in @prisma/prisma-schema-wasm.

prisma.config.ts — the project configuration file introduced in Prisma 7. Replaces datasource URLs / env() in the schema. Loaded by packages/config into a PrismaConfigInternal object that the rest of the toolkit reads.

PSL (Prisma Schema Language) — the DSL used in .prisma files. Has its own parser/validator/formatter, all in Rust, exposed through @prisma/prisma-schema-wasm.

DMMF (Datamodel Meta Format) — the AST representation of a Prisma schema, in JSON. Generated by getDMMF (which calls into the Wasm parser) and consumed by client generators. Defined in packages/dmmf. Note: DMMF is internal with no stability guarantees across minor versions.

Prisma Client — the type-safe query builder generated for each project. The runtime lives in packages/client; the code that emits a Client lives in packages/client-generator-ts (new) or packages/client-generator-js (legacy).

Prisma Migrate — the migrations toolchain (prisma migrate dev, prisma db push, etc.). Implementation in packages/migrate. Talks to the Schema Engine native binary.

Engine vocabulary

Prisma 7 has dropped the term "query engine" entirely. If you see it in older docs or code, mentally translate it to the new architecture below.

Schema Engine — a Rust binary (downloaded by @prisma/engines) that owns introspection, diffing, and migration application. Migrate spawns it as a subprocess and speaks JSON-RPC over stdio (packages/migrate/src/SchemaEngineCLI.ts). A Wasm transport variant exists in SchemaEngineWasm.ts.

Query compiler — the Wasm module from @prisma/query-compiler-wasm. Takes a JSON-protocol query and produces a query plan. Used by ClientEngine in packages/client/src/runtime/core/engines/client/.

Query plan — the intermediate representation produced by the query compiler and consumed by the Query interpreter in packages/client-engine-runtime/src/interpreter/query-interpreter.ts. Type defined in packages/client-engine-runtime/src/query-plan.ts.

ClientEngine — the orchestrator inside Prisma Client that runs query compilation and execution. Lives in packages/client/src/runtime/core/engines/client/ClientEngine.ts. Has two executor implementations: LocalExecutor (driver adapter, direct DB) and RemoteExecutor (Accelerate / Data Proxy).

Driver adapters

Driver adapter — a small package that wraps an existing JS database driver (pg, @neondatabase/serverless, @libsql/client, mssql, etc.) and exposes the SqlDriverAdapter contract from @prisma/driver-adapter-utils. The user passes one to new PrismaClient({ adapter }).

SqlQueryable — the lowest-level adapter interface (queryRaw, executeRaw). Defined in packages/driver-adapter-utils/src/types.ts. Composed into SqlDriverAdapter and Transaction interfaces.

MappedError — the normalized error shape adapters produce. Each adapter's errors.ts (e.g., packages/adapter-pg/src/errors.ts) maps DB-specific codes to a MappedError kind, which rethrowAsUserFacing in packages/client-engine-runtime/src/user-facing-error.ts turns into Prisma's P2xxx error codes.

Generators

prisma-client — the new generator implemented in packages/client-generator-ts. Produces TypeScript output suitable for modern bundlers and ESM, with Wasm-only runtime.

prisma-client-js — the legacy generator in packages/client-generator-js. Still supported and used by older user projects.

Generator registry — packages/client-generator-registry. Hosts the metadata needed to look up and dispatch generators by name.

Generator helper — packages/generator-helper. The IPC contract used by external (out-of-tree) generators. They speak JSON-RPC to the CLI, which is how third-party generators integrate.

Runtime types

Driver Adapter Utils (@prisma/driver-adapter-utils) — the package every adapter depends on. Defines Provider ('mysql' | 'postgres' | 'sqlite' | 'sqlserver'), SqlQuery, SqlQueryable, SqlDriverAdapter, Transaction, MappedError, and ConnectionInfo.

Client common (@prisma/client-common) — shared utilities used by both generators and the runtime.

Client runtime utils (@prisma/client-runtime-utils) — utility types and singletons used inside generated clients.

@prisma/ts-builders — fluent API for emitting TypeScript code. Used by generators to produce .d.ts and .ts output.

Operational vocabulary

Driver flavor — one of the CI test dimensions. Values include js_pg, js_neon, js_libsql, js_planetscale, js_d1, js_better_sqlite3, js_mssql, js_mariadb, js_pg_cockroachdb. Used to parameterize functional tests.

Provider — the database flavor declared in a Prisma schema's datasource block. Always one of postgresql, mysql, sqlite, sqlserver, mongodb, or cockroachdb. (At the driver-adapter layer the spelling is postgres/mysql/sqlite/sqlserver.)

Functional test matrix — the dimension product defined per test under packages/client/tests/functional/<test>/_matrix.ts. See Testing.

Sandbox project — one of the pre-wired example projects in sandbox/ (e.g., basic-sqlite) used as a starting point for reproductions.

integration tag — the npm dist-tag where pre-release builds end up when a branch starts with integration/ or a PR has /integration in its description. Documented in CONTRIBUTING.md and driven by .github/workflows/release-ci.yml.

Conventions

Wasm, not "WASM" — the codebase prefers the official capitalization. Fix incidental "WASM" you see while editing nearby code.

Kebab-case file names — new TypeScript files in this repo are kebab-cased (query-utils.ts, not QueryUtils.ts).

No barrel files — index.ts files that re-export from sibling modules are discouraged for new code. Import from the source file directly (unless an index.ts already exists in that directory).