# Programming Languages and Compilers Development - Processes Backlog

This document contains researched programming languages and compilers development processes that can be adapted to the Babysitter SDK orchestration framework. Each process should be implemented in its own directory under `processes/[name]/`.

## Implementation Guidelines

### Directory Structure
```
processes/
├── [process-name]/
│   ├── README.md              # Overview and usage
│   ├── [process-name].js      # Main process workflow with embedded agentic or skill based tasks, breakpoints, etc.
│   └── examples/              # Example inputs/outputs
│       ├── examples.json
│       └── ...
```

### File Patterns
- **Main Process**: `processes/[name]/[name].js` or `processes/[name].js` (for single-file)
- **JSDoc Required**: `@process`, `@description`, `@inputs`, `@outputs`
- **Export Pattern**: `export async function process(inputs, ctx) { ... }`
- **Task Definitions**: Use `defineTask` from `@a5c-ai/babysitter-sdk`
- **Breakpoints**: Use `ctx.breakpoint()` for human approval gates
- **Parallel Execution**: Use `ctx.parallel.all()` for independent tasks

---

## Priority Matrix

### High Priority (Implement First)
**Core language implementation processes:**
1. **Language Grammar Design** - Formal grammar specification and validation
2. **Lexer Implementation** - Tokenization and lexical analysis
3. **Parser Development** - Syntax analysis and AST construction
4. **AST Design and Traversal** - Abstract syntax tree architecture
5. **Type System Implementation** - Type checking and inference

### Medium Priority (Strategic Processes)
6. **Semantic Analysis** - Name resolution, scope analysis, symbol tables
7. **IR Design and Optimization** - Intermediate representation design
8. **Code Generation (LLVM)** - LLVM-based code generation
9. **Interpreter Implementation** - Tree-walking or bytecode interpreter
10. **REPL Development** - Interactive read-eval-print loop

### Advanced Priority (Specialized Processes)
11. **Bytecode VM Implementation** - Stack or register-based virtual machine
12. **JIT Compiler Development** - Just-in-time compilation
13. **Garbage Collector Implementation** - Automatic memory management
14. **Memory Allocator Design** - Custom memory allocation strategies
15. **Concurrency Primitives** - Threading and synchronization support

### Operational Priority (Tooling Processes)
16. **LSP Server Implementation** - Language Server Protocol support
17. **Debugger Adapter Development** - Debug Adapter Protocol integration
18. **Error Message Enhancement** - Diagnostic quality improvement
19. **Source Map Generation** - Source location mapping
20. **FFI Implementation** - Foreign function interface design

### Extended Priority (Advanced Features)
21. **Macro System Implementation** - Hygienic macro expansion
22. **Module System Design** - Module resolution and loading
23. **Pattern Matching Implementation** - Pattern matching compilation
24. **Generics/Polymorphism** - Parametric polymorphism support
25. **Effect System Design** - Algebraic effects and handlers

---

## 1. Language Grammar Design

**Category**: Language Design
**Priority**: High
**Implementation Status**: Not Started
**Focus Area**: Syntax Specification

### Overview
A systematic process for designing and documenting formal grammars for programming languages. Covers context-free grammar design, disambiguation, and grammar validation.

### Key Principles
- **Unambiguous grammar**: Each valid program has exactly one parse tree
- **Readable syntax**: Balance between familiarity and innovation
- **Error recovery**: Grammar supports meaningful error messages
- **Tooling support**: Grammar amenable to efficient parsing
- **Evolution friendly**: Allow future language extensions

### Implementation Plan

**Directory**: `processes/language-grammar-design/`

**Files to Create**:
1. **`language-grammar-design.js`** - Main grammar design process
   - Syntax brainstorming
   - Grammar formalization
   - Ambiguity analysis
   - Grammar validation

### Process Steps

1. **Define Language Goals**
   - Identify target domain and use cases
   - Define programming paradigm (OOP, FP, procedural, etc.)
   - List desired syntactic features
   - Study similar language syntaxes
   - Output: Language design goals document

2. **Design Core Syntax**
   - Define expression syntax
   - Design statement syntax
   - Specify declaration syntax
   - Define type annotation syntax
   - Output: Informal syntax examples

3. **Formalize Grammar**
   - Convert examples to EBNF/BNF notation
   - Define lexical grammar (tokens)
   - Define syntactic grammar (productions)
   - Specify operator precedence and associativity
   - Output: Formal grammar specification

4. **Analyze Ambiguity**
   - Check for grammar conflicts
   - Identify ambiguous constructs
   - Apply disambiguation rules
   - Resolve dangling-else problems
   - Test with parser generator
   - Output: Unambiguous grammar

5. **Validate Grammar**
   - Test representative programs
   - Verify all language features parseable
   - Check error recovery behavior
   - Review with stakeholders
   - Output: Validated grammar

6. **Document Grammar**
   - Create grammar reference document
   - Add examples for each production
   - Document rationale for design choices
   - Output: Grammar documentation

### Inputs
- Language design goals
- Target use cases
- Reference languages for inspiration
- Parsing strategy (LL, LR, PEG)

### Outputs
- Formal grammar specification (EBNF/BNF)
- Lexical token definitions
- Operator precedence table
- Grammar documentation
- Example programs

### Breakpoints
- After core syntax design for team review
- After formalization for conflict analysis
- After validation for final approval

### SDK Integration Points
- `ctx.breakpoint()` for grammar review gates
- `defineTask` for each design phase
- Grammar validation automation
- Parser generator integration

---

## 2. Lexer Implementation

**Category**: Compiler Frontend
**Priority**: High
**Implementation Status**: Not Started
**Focus Area**: Lexical Analysis

### Overview
A comprehensive process for implementing a lexer (tokenizer) that converts source code into a stream of tokens. Covers both hand-written and generated lexers.

### Key Principles
- **Correctness**: Every valid token recognized correctly
- **Performance**: Efficient single-pass scanning
- **Unicode support**: Handle international characters
- **Position tracking**: Accurate source locations for errors
- **Error recovery**: Continue after invalid tokens

### Implementation Plan

**Directory**: `processes/lexer-implementation/`

**Files to Create**:
1. **`lexer-implementation.js`** - Main lexer implementation process
   - Token design
   - Lexer architecture
   - Unicode handling
   - Testing and validation

### Process Steps

1. **Define Token Types**
   - List all token categories (keywords, operators, literals, etc.)
   - Define token data structures
   - Specify token attributes (value, location, type)
   - Output: Token type enumeration

2. **Design Lexer Architecture**
   - Choose implementation approach (hand-written vs generated)
   - Define state machine (if applicable)
   - Plan lookahead requirements
   - Design error handling strategy
   - Output: Lexer architecture document

3. **Implement Core Scanner**
   - Implement character stream handling
   - Handle whitespace and comments
   - Implement keyword recognition
   - Implement identifier scanning
   - Output: Basic lexer implementation

4. **Implement Literal Scanning**
   - Implement number literals (int, float, hex, binary)
   - Implement string literals (escapes, multiline)
   - Implement character literals
   - Handle special literals (null, true, false)
   - Output: Complete literal handling

5. **Implement Operator Scanning**
   - Implement single-character operators
   - Implement multi-character operators
   - Handle operator ambiguity (e.g., `<` vs `<<` vs `<=`)
   - Output: Operator recognition

6. **Add Source Location Tracking**
   - Track line and column numbers
   - Handle Unicode character widths
   - Create source span structures
   - Output: Position tracking

7. **Implement Error Recovery**
   - Handle invalid characters
   - Recover from unterminated strings
   - Report meaningful error messages
   - Continue scanning after errors
   - Output: Error handling

8. **Test and Validate**
   - Unit tests for each token type
   - Edge case testing
   - Performance benchmarking
   - Fuzz testing
   - Output: Test suite

### Inputs
- Formal grammar specification
- Token definitions
- Unicode requirements
- Performance requirements

### Outputs
- Lexer implementation
- Token type definitions
- Test suite
- Performance benchmarks
- API documentation

### Breakpoints
- After token design for review
- After core implementation for validation
- After error handling for completeness review

### SDK Integration Points
- `ctx.breakpoint()` for implementation review
- `ctx.parallel.all()` for parallel literal implementations
- `defineTask` for each implementation phase
- Automated test execution

---

## 3. Parser Development

**Category**: Compiler Frontend
**Priority**: High
**Implementation Status**: Not Started
**Focus Area**: Syntax Analysis

### Overview
A systematic process for implementing a parser that converts token streams into abstract syntax trees. Covers recursive descent, LALR, and PEG parsing approaches.

### Key Principles
- **Grammar faithful**: Parse tree matches grammar specification
- **Error recovery**: Parse complete file despite errors
- **Performance**: Efficient parsing for large files
- **Extensibility**: Easy to add new grammar rules
- **Diagnostics**: Clear error messages with suggestions

### Implementation Plan

**Directory**: `processes/parser-development/`

**Files to Create**:
1. **`parser-development.js`** - Main parser development process
   - Parsing strategy selection
   - Parser implementation
   - Error recovery
   - AST construction

### Process Steps

1. **Select Parsing Strategy**
   - Analyze grammar complexity
   - Evaluate LL(k), LR, LALR, PEG, Pratt parsing
   - Consider tooling constraints
   - Make technology decision
   - Output: Parsing strategy ADR

2. **Design Parser Architecture**
   - Define parser interface
   - Plan token lookahead handling
   - Design error recovery approach
   - Plan AST construction strategy
   - Output: Parser architecture document

3. **Implement Expression Parser**
   - Handle operator precedence
   - Implement prefix expressions
   - Implement infix expressions
   - Handle postfix expressions
   - Use Pratt parsing for expressions
   - Output: Expression parser

4. **Implement Statement Parser**
   - Parse variable declarations
   - Parse control flow statements
   - Parse function definitions
   - Parse type declarations
   - Output: Statement parser

5. **Implement Declaration Parser**
   - Parse top-level declarations
   - Handle imports/modules
   - Parse class/struct definitions
   - Parse interface/trait definitions
   - Output: Declaration parser

6. **Implement Error Recovery**
   - Synchronize on statement boundaries
   - Handle missing tokens
   - Handle unexpected tokens
   - Provide error suggestions
   - Output: Error recovery system

7. **Implement Error Messages**
   - Format error locations
   - Provide context in messages
   - Add fix suggestions
   - Support different output formats
   - Output: Diagnostic system

8. **Test and Validate**
   - Parse valid programs
   - Test error cases
   - Test recovery behavior
   - Performance testing
   - Output: Comprehensive test suite

### Inputs
- Formal grammar specification
- Lexer implementation
- AST node definitions
- Error message requirements

### Outputs
- Parser implementation
- Error recovery system
- Diagnostic messages
- Test suite
- Parser documentation

### Breakpoints
- After strategy selection for approval
- After expression parser for review
- After error recovery for quality check

### SDK Integration Points
- `ctx.breakpoint()` for design approvals
- `ctx.parallel.all()` for parallel parser component development
- `defineTask` for each parser phase
- Grammar validation integration

---

## 4. AST Design and Traversal

**Category**: Compiler Infrastructure
**Priority**: High
**Implementation Status**: Not Started
**Focus Area**: Data Structures

### Overview
A process for designing abstract syntax tree structures and implementing traversal patterns. Covers node design, visitor patterns, and tree transformations.

### Key Principles
- **Type safety**: Strong typing for AST nodes
- **Immutability**: Prefer immutable AST structures
- **Span preservation**: Track source locations
- **Visitor friendly**: Support multiple traversal patterns
- **Serializable**: Support caching and tooling

### Implementation Plan

**Directory**: `processes/ast-design/`

**Files to Create**:
1. **`ast-design.js`** - Main AST design process
   - Node hierarchy design
   - Visitor implementation
   - Tree transformation utilities

### Process Steps

1. **Analyze Grammar for Nodes**
   - Map grammar productions to AST nodes
   - Identify shared node structures
   - Plan node hierarchy
   - Output: Node catalog

2. **Design Node Hierarchy**
   - Define base node type
   - Create expression node types
   - Create statement node types
   - Create declaration node types
   - Create type node types
   - Output: AST type definitions

3. **Implement Span Tracking**
   - Design span structure
   - Add spans to all nodes
   - Handle synthetic nodes
   - Output: Span infrastructure

4. **Implement Visitor Pattern**
   - Define visitor interface
   - Implement base visitor
   - Create typed visitors
   - Support multiple traversal orders
   - Output: Visitor framework

5. **Implement Tree Transformations**
   - Create tree map utilities
   - Implement tree fold utilities
   - Build rewrite framework
   - Output: Transformation utilities

6. **Add Serialization Support**
   - Implement JSON serialization
   - Add binary serialization (optional)
   - Support round-trip preservation
   - Output: Serialization support

7. **Test and Validate**
   - Test each node type
   - Test visitor traversals
   - Test transformations
   - Validate span accuracy
   - Output: Test suite

### Inputs
- Grammar specification
- Language requirements
- Tooling requirements
- Performance requirements

### Outputs
- AST node definitions
- Visitor framework
- Transformation utilities
- Serialization support
- Test suite
- API documentation

### Breakpoints
- After node hierarchy design for review
- After visitor implementation for validation

### SDK Integration Points
- `ctx.breakpoint()` for design review
- `defineTask` for each design phase
- AST visualization integration

---

## 5. Type System Implementation

**Category**: Semantic Analysis
**Priority**: High
**Implementation Status**: Not Started
**Focus Area**: Type Checking

### Overview
A comprehensive process for implementing type checking and type inference. Covers type representation, checking algorithms, and error reporting.

### Key Principles
- **Soundness**: Well-typed programs don't go wrong
- **Completeness**: Accept all safe programs (when possible)
- **Inference**: Reduce annotation burden
- **Error quality**: Clear type error messages
- **Performance**: Efficient type checking

### Implementation Plan

**Directory**: `processes/type-system-implementation/`

**Files to Create**:
1. **`type-system-implementation.js`** - Main type system process
   - Type representation
   - Type checking
   - Type inference
   - Error reporting

### Process Steps

1. **Design Type Representation**
   - Define primitive types
   - Design composite types (arrays, tuples)
   - Design function types
   - Design user-defined types
   - Handle type parameters (generics)
   - Output: Type data structures

2. **Implement Type Environment**
   - Design type environment structure
   - Implement scope management
   - Handle type bindings
   - Support type aliases
   - Output: Type environment

3. **Implement Type Checking**
   - Check expression types
   - Check statement types
   - Validate declarations
   - Check subtyping relations
   - Output: Type checker

4. **Implement Type Inference**
   - Implement constraint generation
   - Implement unification algorithm
   - Handle let-polymorphism
   - Implement bidirectional inference
   - Output: Type inference system

5. **Implement Subtyping**
   - Define subtyping rules
   - Implement subtype checking
   - Handle variance (co/contra/invariant)
   - Support structural or nominal typing
   - Output: Subtyping system

6. **Implement Error Reporting**
   - Design type error messages
   - Show expected vs actual types
   - Provide fix suggestions
   - Handle error cascades
   - Output: Type error diagnostics

7. **Test and Validate**
   - Test type checking correctness
   - Test inference completeness
   - Test error messages
   - Benchmark performance
   - Output: Test suite

### Inputs
- Language type rules
- AST definitions
- Subtyping requirements
- Inference requirements

### Outputs
- Type representation
- Type checker implementation
- Type inference system
- Error messages
- Test suite
- Type system documentation

### Breakpoints
- After type representation for design review
- After type checking for correctness validation
- After inference for completeness testing

### SDK Integration Points
- `ctx.breakpoint()` for design approvals
- `ctx.parallel.all()` for parallel feature development
- `defineTask` for each implementation phase
- Type checking test automation

---

## 6. Semantic Analysis

**Category**: Compiler Frontend
**Priority**: Medium
**Implementation Status**: Not Started
**Focus Area**: Name Resolution and Validation

### Overview
A process for implementing semantic analysis including name resolution, scope analysis, symbol table management, and semantic validation.

### Key Principles
- **Completeness**: Catch all semantic errors
- **Accuracy**: Correct scope and binding
- **Performance**: Efficient symbol lookup
- **Diagnostics**: Helpful error messages

### Implementation Plan

**Directory**: `processes/semantic-analysis/`

**Process Steps**

1. **Design Symbol Table**
   - Define symbol entry structure
   - Plan scope representation
   - Handle nested scopes
   - Support module namespaces
   - Output: Symbol table design

2. **Implement Name Resolution**
   - Resolve variable references
   - Resolve type references
   - Resolve function calls
   - Handle forward references
   - Output: Name resolver

3. **Implement Scope Analysis**
   - Build scope tree
   - Validate variable declarations
   - Check duplicate definitions
   - Handle shadowing rules
   - Output: Scope analyzer

4. **Implement Semantic Checks**
   - Validate control flow (break/continue placement)
   - Check return statement coverage
   - Validate initialization
   - Check mutability violations
   - Output: Semantic validator

5. **Test and Validate**
   - Test scoping rules
   - Test error detection
   - Verify error messages
   - Output: Test suite

### Inputs
- AST definitions
- Language scoping rules
- Semantic constraints

### Outputs
- Symbol table implementation
- Name resolution system
- Scope analyzer
- Semantic validator
- Test suite

### Breakpoints
- After symbol table design for review
- After semantic checks for validation

---

## 7. IR Design and Optimization

**Category**: Compiler Middle-end
**Priority**: Medium
**Implementation Status**: Not Started
**Focus Area**: Intermediate Representation

### Overview
A process for designing intermediate representations and implementing optimization passes. Covers IR design, SSA form, and common optimizations.

### Key Principles
- **Simplicity**: Simple instruction set for optimization
- **Expressiveness**: Represent all source constructs
- **Target independence**: Decouple from machine details
- **Analysis friendly**: Enable efficient data-flow analysis

### Implementation Plan

**Directory**: `processes/ir-design/`

**Process Steps**

1. **Design IR Instruction Set**
   - Define core operations
   - Design control flow representation
   - Handle function calls
   - Support memory operations
   - Output: IR specification

2. **Implement IR Builder**
   - Create IR construction API
   - Lower AST to IR
   - Handle complex expressions
   - Output: IR builder

3. **Implement SSA Construction**
   - Build dominance tree
   - Insert phi functions
   - Rename variables
   - Output: SSA form IR

4. **Implement Basic Optimizations**
   - Constant folding
   - Dead code elimination
   - Copy propagation
   - Common subexpression elimination
   - Output: Optimization passes

5. **Implement Control Flow Optimizations**
   - Unreachable code elimination
   - Branch simplification
   - Loop optimizations
   - Output: CFG optimizations

6. **Test and Validate**
   - Verify IR correctness
   - Benchmark optimizations
   - Test edge cases
   - Output: Test suite

### Inputs
- AST definitions
- Optimization goals
- Target requirements

### Outputs
- IR specification
- IR builder
- SSA construction
- Optimization passes
- Test suite

### Breakpoints
- After IR design for review
- After SSA for correctness validation

---

## 8. Code Generation (LLVM)

**Category**: Compiler Backend
**Priority**: Medium
**Implementation Status**: Not Started
**Focus Area**: Native Code Generation

### Overview
A process for implementing code generation using LLVM. Covers LLVM IR generation, optimization passes, and machine code emission.

### Key Principles
- **Correctness**: Generated code matches semantics
- **Optimization**: Leverage LLVM optimization passes
- **Debug support**: Generate debug information
- **Cross-platform**: Support multiple targets

### Implementation Plan

**Directory**: `processes/code-generation-llvm/`

**Process Steps**

1. **Set Up LLVM Infrastructure**
   - Initialize LLVM context
   - Create module and builder
   - Configure target machine
   - Output: LLVM setup

2. **Implement Type Mapping**
   - Map language types to LLVM types
   - Handle aggregate types
   - Handle function types
   - Output: Type codegen

3. **Implement Expression Codegen**
   - Generate arithmetic operations
   - Generate comparisons
   - Generate function calls
   - Handle control flow in expressions
   - Output: Expression codegen

4. **Implement Statement Codegen**
   - Generate variable operations
   - Generate control flow
   - Generate function definitions
   - Output: Statement codegen

5. **Implement Runtime Support**
   - Generate runtime call stubs
   - Handle memory allocation
   - Implement exception handling
   - Output: Runtime integration

6. **Enable Optimizations**
   - Configure optimization pipeline
   - Apply standard passes
   - Tune for size or speed
   - Output: Optimization configuration

7. **Generate Debug Information**
   - Create debug metadata
   - Map source locations
   - Support DWARF/CodeView
   - Output: Debug info generation

8. **Test and Validate**
   - Test generated code execution
   - Verify optimization results
   - Test debug information
   - Output: Test suite

### Inputs
- IR specification
- LLVM version requirements
- Target architectures
- Debug requirements

### Outputs
- LLVM IR generator
- Optimization configuration
- Debug info generator
- Test suite
- Codegen documentation

### Breakpoints
- After type mapping for review
- After statement codegen for validation
- After debug info for completeness check

---

## 9. Interpreter Implementation

**Category**: Runtime
**Priority**: Medium
**Implementation Status**: Not Started
**Focus Area**: Direct Execution

### Overview
A process for implementing an interpreter for direct program execution. Covers both tree-walking and bytecode interpreter approaches.

### Key Principles
- **Correctness**: Match language semantics exactly
- **Interactivity**: Fast startup for REPL use
- **Debugging**: Easy to debug and extend
- **Bootstrapping**: Enable language development

### Implementation Plan

**Directory**: `processes/interpreter-implementation/`

**Process Steps**

1. **Choose Interpreter Strategy**
   - Evaluate tree-walking vs bytecode
   - Consider hybrid approaches
   - Make architecture decision
   - Output: Strategy ADR

2. **Implement Value Representation**
   - Define value types
   - Handle boxed vs unboxed values
   - Implement type tags
   - Output: Value system

3. **Implement Environment**
   - Create variable bindings
   - Handle scopes
   - Implement closures
   - Output: Environment system

4. **Implement Expression Evaluation**
   - Evaluate literals
   - Evaluate operators
   - Evaluate function calls
   - Output: Expression interpreter

5. **Implement Statement Execution**
   - Execute declarations
   - Execute control flow
   - Execute function definitions
   - Output: Statement interpreter

6. **Implement Built-in Functions**
   - Add I/O primitives
   - Add math functions
   - Add string operations
   - Output: Standard library

7. **Test and Validate**
   - Test semantics correctness
   - Test edge cases
   - Benchmark performance
   - Output: Test suite

### Inputs
- Language semantics
- AST definitions
- Performance requirements

### Outputs
- Interpreter implementation
- Value representation
- Built-in library
- Test suite

### Breakpoints
- After strategy selection for approval
- After expression evaluation for correctness

---

## 10. REPL Development

**Category**: Tooling
**Priority**: Medium
**Implementation Status**: Not Started
**Focus Area**: Interactive Development

### Overview
A process for building an interactive REPL (Read-Eval-Print Loop) for the language. Covers input handling, evaluation, output formatting, and user experience.

### Key Principles
- **Responsiveness**: Fast evaluation feedback
- **Usability**: Good editing experience
- **Informativeness**: Helpful output and errors
- **Extensibility**: Support for customization

### Implementation Plan

**Directory**: `processes/repl-development/`

**Process Steps**

1. **Implement Input Handling**
   - Integrate readline library
   - Handle multi-line input
   - Implement bracket matching
   - Add history support
   - Output: Input system

2. **Implement Incremental Parsing**
   - Detect complete expressions
   - Request continuation for incomplete input
   - Handle syntax errors gracefully
   - Output: REPL parser

3. **Implement Evaluation**
   - Manage REPL state
   - Handle definitions
   - Support expression results
   - Output: REPL evaluator

4. **Implement Output Formatting**
   - Pretty-print values
   - Format complex structures
   - Truncate large outputs
   - Add color support
   - Output: Output formatter

5. **Implement Commands**
   - Add help command
   - Add quit command
   - Add load file command
   - Add type information command
   - Output: REPL commands

6. **Add Completion Support**
   - Complete identifiers
   - Complete keywords
   - Complete file paths
   - Output: Tab completion

7. **Test and Validate**
   - Test interactive scenarios
   - Test error handling
   - Test completion accuracy
   - Output: Test suite

### Inputs
- Interpreter/compiler
- Language features
- UX requirements

### Outputs
- REPL implementation
- Command system
- Completion system
- Test suite

### Breakpoints
- After input handling for UX review
- After completion for usability testing

---

## 11. Bytecode VM Implementation

**Category**: Runtime
**Priority**: Advanced
**Implementation Status**: Not Started
**Focus Area**: Virtual Machine

### Overview
A process for implementing a bytecode virtual machine. Covers instruction set design, stack or register architecture, and execution optimization.

### Process Steps

1. **Design Instruction Set**
2. **Choose VM Architecture** (stack vs register)
3. **Implement Bytecode Compiler**
4. **Implement VM Execution Loop**
5. **Implement Stack Management**
6. **Add Runtime Support**
7. **Optimize Dispatch**
8. **Test and Validate**

### Outputs
- Bytecode specification
- Bytecode compiler
- VM implementation
- Test suite

---

## 12. JIT Compiler Development

**Category**: Runtime Optimization
**Priority**: Advanced
**Implementation Status**: Not Started
**Focus Area**: Dynamic Compilation

### Overview
A process for implementing just-in-time compilation to improve runtime performance. Covers profiling, compilation triggers, and deoptimization.

### Process Steps

1. **Design Profiling System**
2. **Implement Compilation Triggers**
3. **Implement Code Generation**
4. **Implement Optimization Tiers**
5. **Implement Deoptimization**
6. **Implement Code Cache**
7. **Test and Validate**

### Outputs
- Profiling system
- JIT compiler
- Code cache
- Test suite

---

## 13. Garbage Collector Implementation

**Category**: Memory Management
**Priority**: Advanced
**Implementation Status**: Not Started
**Focus Area**: Automatic Memory Management

### Overview
A process for implementing garbage collection. Covers GC algorithm selection, implementation, and tuning.

### Process Steps

1. **Choose GC Algorithm**
2. **Design Object Layout**
3. **Implement Allocation**
4. **Implement Mark Phase**
5. **Implement Sweep/Compact/Copy**
6. **Implement Write Barriers** (if needed)
7. **Add GC Tuning**
8. **Test and Validate**

### Outputs
- GC implementation
- Object layout specification
- Tuning parameters
- Test suite

---

## 14. Memory Allocator Design

**Category**: Memory Management
**Priority**: Advanced
**Implementation Status**: Not Started
**Focus Area**: Custom Allocation

### Overview
A process for designing custom memory allocators optimized for language runtime needs.

### Process Steps

1. **Analyze Allocation Patterns**
2. **Design Allocator Strategy**
3. **Implement Small Object Allocator**
4. **Implement Large Object Handling**
5. **Add Thread Safety**
6. **Benchmark and Tune**
7. **Test and Validate**

### Outputs
- Memory allocator implementation
- Allocation statistics
- Performance benchmarks
- Test suite

---

## 15. Concurrency Primitives

**Category**: Runtime
**Priority**: Advanced
**Implementation Status**: Not Started
**Focus Area**: Thread Support

### Overview
A process for implementing language-level concurrency primitives including threads, channels, and synchronization.

### Process Steps

1. **Design Concurrency Model**
2. **Implement Thread Creation**
3. **Implement Synchronization Primitives**
4. **Implement Channels/Message Passing**
5. **Handle Thread-Local Storage**
6. **Add Debugging Support**
7. **Test and Validate**

### Outputs
- Concurrency primitives
- Synchronization library
- Thread debugging support
- Test suite

---

## 16. LSP Server Implementation

**Category**: Tooling
**Priority**: Operational
**Implementation Status**: Not Started
**Focus Area**: Editor Integration

### Overview
A process for implementing a Language Server Protocol server for IDE integration.

### Process Steps

1. **Set Up LSP Framework**
2. **Implement Document Synchronization**
3. **Implement Diagnostics**
4. **Implement Completion**
5. **Implement Go-to-Definition**
6. **Implement Hover Information**
7. **Implement Rename**
8. **Test and Validate**

### Outputs
- LSP server implementation
- Capability documentation
- Editor configuration
- Test suite

---

## 17. Debugger Adapter Development

**Category**: Tooling
**Priority**: Operational
**Implementation Status**: Not Started
**Focus Area**: Debug Support

### Overview
A process for implementing debug adapter protocol support for debugger integration.

### Process Steps

1. **Set Up DAP Framework**
2. **Implement Breakpoints**
3. **Implement Stepping**
4. **Implement Stack Traces**
5. **Implement Variable Inspection**
6. **Implement Expression Evaluation**
7. **Test and Validate**

### Outputs
- Debug adapter implementation
- Debug symbol format
- Editor integration
- Test suite

---

## 18. Error Message Enhancement

**Category**: User Experience
**Priority**: Operational
**Implementation Status**: Not Started
**Focus Area**: Diagnostics Quality

### Overview
A process for improving error message quality across the compiler/interpreter.

### Process Steps

1. **Audit Existing Errors**
2. **Design Message Templates**
3. **Add Source Context**
4. **Implement Fix Suggestions**
5. **Add Related Information**
6. **Implement Color Output**
7. **Test with Users**

### Outputs
- Enhanced error messages
- Message style guide
- User testing results
- Documentation

---

## 19. Source Map Generation

**Category**: Tooling
**Priority**: Operational
**Implementation Status**: Not Started
**Focus Area**: Source Mapping

### Overview
A process for generating source maps to map generated code back to source.

### Process Steps

1. **Design Source Map Format**
2. **Track Source Positions**
3. **Implement Map Generation**
4. **Integrate with Debugger**
5. **Test Accuracy**

### Outputs
- Source map generator
- Debugger integration
- Test suite

---

## 20. FFI Implementation

**Category**: Interoperability
**Priority**: Operational
**Implementation Status**: Not Started
**Focus Area**: Foreign Functions

### Overview
A process for implementing foreign function interface for calling native code.

### Process Steps

1. **Design FFI Syntax**
2. **Implement Type Marshaling**
3. **Implement Call Convention Handling**
4. **Support Library Loading**
5. **Handle Callbacks**
6. **Test Safety**

### Outputs
- FFI specification
- Marshaling implementation
- Safety documentation
- Test suite

---

## 21. Macro System Implementation

**Category**: Metaprogramming
**Priority**: Extended
**Implementation Status**: Not Started
**Focus Area**: Syntactic Abstraction

### Overview
A process for implementing a macro system for syntactic abstraction.

### Process Steps

1. **Design Macro Syntax**
2. **Implement Macro Parsing**
3. **Implement Hygiene**
4. **Implement Expansion**
5. **Handle Macro Errors**
6. **Test and Validate**

### Outputs
- Macro system implementation
- Hygiene documentation
- Example macros
- Test suite

---

## 22. Module System Design

**Category**: Language Features
**Priority**: Extended
**Implementation Status**: Not Started
**Focus Area**: Code Organization

### Overview
A process for designing and implementing a module system for code organization.

### Process Steps

1. **Design Module Syntax**
2. **Implement Module Resolution**
3. **Implement Import/Export**
4. **Handle Cyclic Dependencies**
5. **Implement Visibility**
6. **Test and Validate**

### Outputs
- Module system implementation
- Resolution algorithm
- Test suite

---

## 23. Pattern Matching Implementation

**Category**: Language Features
**Priority**: Extended
**Implementation Status**: Not Started
**Focus Area**: Pattern Matching

### Overview
A process for implementing pattern matching including compilation to decision trees.

### Process Steps

1. **Design Pattern Syntax**
2. **Implement Pattern Parsing**
3. **Implement Exhaustiveness Checking**
4. **Compile to Decision Tree**
5. **Implement Guards**
6. **Test and Validate**

### Outputs
- Pattern matching implementation
- Exhaustiveness checker
- Test suite

---

## 24. Generics/Polymorphism Implementation

**Category**: Type System
**Priority**: Extended
**Implementation Status**: Not Started
**Focus Area**: Parametric Polymorphism

### Overview
A process for implementing generics or parametric polymorphism.

### Process Steps

1. **Design Generic Syntax**
2. **Implement Type Parameter Parsing**
3. **Implement Instantiation**
4. **Handle Monomorphization vs Erasure**
5. **Implement Bounds/Constraints**
6. **Test and Validate**

### Outputs
- Generics implementation
- Constraint system
- Test suite

---

## 25. Effect System Design

**Category**: Type System
**Priority**: Extended
**Implementation Status**: Not Started
**Focus Area**: Effect Tracking

### Overview
A process for designing an effect system to track computational effects in the type system.

### Process Steps

1. **Design Effect Annotation Syntax**
2. **Implement Effect Inference**
3. **Implement Effect Checking**
4. **Handle Effect Polymorphism**
5. **Implement Effect Handlers** (if algebraic)
6. **Test and Validate**

### Outputs
- Effect system implementation
- Effect documentation
- Test suite

---

## Summary

This backlog contains **25 programming languages and compilers development processes** organized into five priority tiers:

**High Priority (5 processes)**: Core language implementation
**Medium Priority (5 processes)**: Strategic language tooling
**Advanced Priority (5 processes)**: Performance and memory management
**Operational Priority (5 processes)**: Developer tooling
**Extended Priority (5 processes)**: Advanced language features

These processes cover the key focus areas requested:
- Language grammar design
- Lexer implementation
- Parser development (recursive descent, LALR, PEG)
- AST design and traversal
- Type system implementation
- Semantic analysis
- IR design and optimization
- Code generation (LLVM, native)
- Interpreter implementation
- REPL development

Each process is designed to integrate with the Babysitter SDK orchestration framework using `defineTask`, `ctx.breakpoint()`, and `ctx.parallel.all()` patterns.

## Next Steps

1. **Implement High Priority processes first** (Grammar, Lexer, Parser, AST, Type System)
2. **Create process templates** for consistent implementation
3. **Build reusable task libraries** for common compiler activities
4. **Integrate with existing tools** (ANTLR, LLVM, tree-sitter)
5. **Gather feedback** from language implementers
6. **Iterate and improve** based on real-world usage
