GEPs for Groovy

Here you can find the GEPs for the Groovy programming language:

• GEP-1: Groovy Enhancement Proposal

  Status: Final

• GEP-2: AST Builder Support

  Status: Final | Target: Groovy 1.7 | Comment: Included in Groovy but somewhat _superseded by macros_

• GEP-3: Command Expression based DSL

  Status: Final | Target: Groovy 1.8 or 2.0 | Comment: Included in Groovy and has been further enhanced

• GEP-4: AstBuilder AST Templates

  Status: Rejected | Comment: The approach used in Groovy macros was pursued instead

• GEP-5: File extension dependent AST transformations

  Status: Rejected | Comment: Groovy 1.8 instead adopted a general compiler configuration mechanism

• GEP-6: NIO2 Support for Groovy

  Status: Final | Comment: Delivered in Groovy 2.3

• GEP-7: JSON Support

  Status: Final | Comment: Delivered in Groovy 1.8

• GEP-8: Static type checking

  Status: Final | Comment: Delivered in Groovy 2.0 and enhanced in later versions

• GEP-9: Modularization

  Status: Final | Comment: Parts incorporated in Groovy 2.0

• GEP-10: Static compilation

  Status: Final | Comment: Delivered in Groovy 2.0 and enhanced in later versions

• GEP-11: Groovy 3 semantics and new MOP

  Status: Draft | Last modification: 2018-10-28

• GEP-12: SAM coercion

  Status: Final

• GEP-13: Sealed Types

  Status: Final

• GEP-14: Record classes

  Status: Final

• GEP-15: Compound assignment operator overloading

  Status: Accepted

• GEP-16: val type placeholder for final declarations

  Status: Final

• GEP-17: Consistent handling of internal properties via @Internal

  Status: Draft | Last modification: 2026-04-14

• GEP-18: Integrated Concurrency and Parallel Processing

  Status: Final

• GEP-19: Structural Pattern Matching in switch

  Status: Draft | Last modification: 2026-04-25

• GEP-20: Multi-assignment Destructuring

  Status: Accepted

• GEP-21: Broadening AST transform awareness under joint compilation

  Status: Accepted

• GEP-22: Traits

  Status: Final | Comment: Reflects trait semantics as of Groovy 6

• GEP-23: Monadic comprehensions

  Status: Final | Comment: Delivered in Groovy 6.0 as an incubating feature via the `DO` macro; subject to refinement during the 6.x line

• GEP-24: Errors as values — compile-time Try without the wrapper

  Status: Draft | Last modification: 2026-05-21 | Comment: Targets Groovy 7.0; the spec-side checker (`@Raises` + `ExceptionChecker`) may incubate earlier in a Groovy 6.x point release

• GEP-25: Data-flow Security — Taint Tracking and Sensitive-data Redaction

  Status: Draft (placeholder)

• GEP-26: GINQ SQL Backend (Native and JOOQ Providers)

  Status: Draft | Last modification: 2026-07-04 | Target: Groovy 7.0 | Comment: Builds on the existing GINQ collection provider and the `groupby...into` group model; strictly additive and opt-in. Version 2 aligns the document with the reference implementation (see _Reference implementation_).

• GEP-27: Compact Closure and Lambda Compilation

  Status: Draft | Last modification: 2026-07-17 | Target: Groovy 6.0 (SAM lambdas merged; closure packing a stretch goal) and Groovy 7.0 (object elision, writer unification) | Comment: Reduces the per-closure/per-lambda generated-class explosion by hoisting bodies onto the enclosing class. The sound-by-construction SAM-lambda slice is merged for Groovy 6; closure packing (S1) is implemented and proposed as a Groovy 6 stretch goal (GROOVY-12151); object elision and writer unification remain for Groovy 7. Strictly additive; gated by a flag for back-out.

• GEP-28: Dot Shorthands (Context-Typed Member Access)

  Status: Draft | Last modification: 2026-07-25 | Target: Groovy 7.0 | Comment: A leading-dot shorthand (`.RED`) that resolves a member against the type expected by the surrounding context, following Dart 3.10's dot shorthands and Swift's implicit member expressions. Closes the remaining "enum values without imports" gaps that neither unqualified switch-case constants (GROOVY-8444) nor String-to-enum coercion can reach — method arguments, annotation attributes, `==` comparisons, typed collection literals, and dynamic-mode case labels — while adding compile-time member checking everywhere it is used. Strictly additive: every proposed form is a syntax error today.

In addition, smaller GEPs are tracked as issues in Jira:

• GROOVY-12126: Non-local control flow from closures (return / break / continue) (open)
• GROOVY-12122: Provide a Regex timeout facility
• GROOVY-12115: Reify a receiver's type argument as a Class parameter under @CompileStatic (@ClassTag) (open)
• GROOVY-11940: Provide an optional groovy-markdown module with a slurper
• GROOVY-11923: Provide a groovy-csv optional module
• GROOVY-11879: A very simple DSL over the JDK's HTTP client
• GROOVY-11166: JEP 445 compatibility
• GROOVY-10943: Treat multiple underscores as placeholders in multi-assignment statements and closure/lambda parameters
• GROOVY-9804: Support TOML
• GROOVY-9680: Groovy 4 should provide some pre-canned type checker extensions
• GROOVY-9671: Absorb GContracts project into Groovy project
• GROOVY-9442: GEP: Support for the new JDK14 string escape sequence (\s for single space)
• GROOVY-9381: Add native async/await support
• GROOVY-9365: Implement JavaShell to run Java code
• GROOVY-8794: Add optional groovy-yaml subproject to support parsing and building yaml
• GROOVY-8431: toDebugString method as a core concept (open)
• GROOVY-8258: [GEP] Create a LINQ-like DSL (basic cases)
• GROOVY-7957: Allow static compilation of builders that implement methodMissing / propertyMissing
• GROOVY-7956: Provide an AST transformation which improves named parameter support
• GROOVY-4384: Implement GEP-3: extended command expressions
• GROOVY-1884: GEP: Adding Bound Properties to GroovyBeans
• GROOVY-1709: GEP: Groovy Enhancement Proposal
• GROOVY-158: Multiple assignment