Simple is a self-hosted language and toolchain that combines a readable Python-like surface with compiler-integrated testing, documentation, architecture rules, and baremetal-oriented execution paths.

The repo is unusually broad: language, compiler, interpreter, loader, test runner, doc generation, traceability tooling, SDN-backed project databases, editor tooling, and hardware-oriented test flows all live together.

Quick Navigation: Distinctive Features | Feature Status | Quick Start | Language Basics | Examples | Editor Plugins | Documentation

• Self-hosted staged toolchain: real source layers for frontend, type analysis, borrow checking, backend, driver, interpreter, and loader live in-tree.
• Verification-native workflow: SSpec BDD tests, SDoctest executable docs, coverage, traceability checks, and generated spec docs are part of the toolchain rather than bolted on.
• MDSOC architecture support: virtual capsules, manifests, and architecture-aware repository structure are first-class concepts.
• Parser-friendly macro system: macro definitions, expansion, validation, and hygiene are compiler features rather than editor-hostile text substitution.
• Math-oriented syntax blocks: m{}, loss{}, and nograd{} are implemented syntax with parsing, evaluation, five rendering backends (text, debug, Unicode, LaTeX, Markdown), and editor integration (query/LSP hover, VSCode highlighting/preview, Neovim inline Unicode preview with conceal). The autograd path is complete for the promoted torch-backed C/LLVM scope.
• SDN-backed textual databases: tests, todos, dashboards, and other project metadata are stored through repo-native SDN data flows.
• Multiple execution paths: interpreter, loader, SMF/module loading, and native/LLVM-oriented compilation paths coexist in one system.
• Baremetal-oriented build and test plumbing: QEMU, semihosting, MMIO mailbox, remote baremetal flows, and adapter-backed hardware lanes (8 authoritative) are built into the repo story.
• Tooling-aware language rules: Tree-sitter integration, primitive-public-API linting, traceability tooling, and language statistics are part of the platform.
• Shared UI contract across supported surfaces: one HTTP-based test protocol (Protocol V1) with UITestClient drives both the web backend and the TUI-web proxy through a shared handle_test_request handler, verified by a cross-surface contract suite. Contract: doc/04_architecture/shared_ui_contract.md

Implemented and safe to advertise:

• SSpec, SDoctest, coverage, traceability checks, and generated spec docs
• SSpec mock policy: system-test mock ban, HAL-only and custom pattern modes
• Self-hosted staged compiler, interpreter, and loader architecture
• MDSOC manifests and architecture-focused project structure
• Parser-friendly macros with validation and hygiene
• Tree-sitter outline/query tooling
• SDN-backed project, test, and todo databases
• Primitive-public-API linting and semantic wrapper/unit-type patterns
• Borrow-checking infrastructure
• Watch mode and auto-build support
• mmap-backed loader support and executable-memory plumbing
• Baremetal build/test plumbing and host-aware remote baremetal flows
• C/C++ bidirectional SFFI for the supported ABI subset: exports, imports, callback trampolines, layout verification, and round-trip proof tests

Implemented, but best described with qualifiers:

• LLVM full-family closure is complete for the declared public matrix: every llvm-lib and llvm backend row is now explicitly stable or unsupported, with no ambiguous middle states. rust-llvm remains a bootstrap-only seed path outside the public family claim
• Lean verification workflow is complete for the supported verification subset: deterministic Lean generation, proof artifact inventory, Lean/Lake checking, cache invalidation, and verification-state reporting. Contract: doc/04_architecture/lean_verification_contract.md. Report: doc/09_report/lean_verification_complete_2026-04-04.md
• GC and no-GC runtime families: 5 public families (common, nogc_sync_mut, nogc_async_mut, gc_async_mut, nogc_async_mut_noalloc) with compiler boundary enforcement, interpreter warnings, and target preset mapping. Support matrix: doc/04_architecture/runtime_family_support_matrix.md
• Shared UI contract across web backend and TUI-web proxy (Protocol V1): shared handler, structured error model, stable element IDs, cross-surface contract suite — but this is a shared test protocol, not a full unified UI rendering layer
• Remote baremetal execution has 8 authoritative lanes (3 stable + 5 host-aware including both GHDL semihost and mailbox simulation), but hardware-dependent lanes remain host- and board-aware rather than universally complete. Lane matrix: doc/08_tracking/lane_matrix.md

Implemented with bounded scope:

• m{} / loss{} / nograd{} are complete for the promoted torch-backed C/LLVM scope, including backward, detached-input failure, and nograd{} restore semantics. Other backends remain deferred
• AOP provides predicate-based pointcuts (execution, within, attr), deterministic before/after/around advice, compile-time weaving as the default backend, and scoped runtime interception. Support matrix: doc/05_design/aop_support_matrix.md
• VHDL backend compiles a documented hardware-oriented Simple subset to synthesizable VHDL-2008, validated through GHDL analysis/elaboration. Strict fail-fast on unsupported constructs. Two GHDL RV32 simulation lanes are operational: semihost (GDB-backed, ARM semihosting traps) and mailbox (debugger-independent, MMIO at 0x80FF0000 with ram_sentinel result collection). Support matrix: doc/04_architecture/vhdl_support_matrix.md. Mailbox protocol: doc/04_architecture/ghdl_rv32_mailbox_protocol.md

Implemented:

• Anti-dummy / anti-stub enforcement is active on the primary source and compiled CLI surfaces (simple lint, simple verify quality). All public-facing proof suites (SFFI, T32 hardware, compiler/runtime/system) now pass the gate. Remaining debt is only in deferred OS/GPU/experimental areas — all active surfaces are clean.

See doc/report/unique_features.md for the evidence-backed audit.

Simple organizes its standard library into runtime families based on allocation, mutation, and concurrency requirements:

The compiler enforces family boundaries: importing a GC module from a no-GC context produces a diagnostic warning. Target presets (Baremetal, Hosted, EmbeddedWithHeap) automatically restrict module resolution to compatible families.

For advanced use: nogc_async_immut provides persistent data structures with lock-free concurrency.

See Runtime Family Support Matrix for full contracts, and Known Limitations for current caveats.

Download the pre-compiled release for your platform - no build required!

What you get:

• Pre-compiled runtime (10 MB optimized binary)
• Complete Simple compiler (100% Simple source code)
• Standard library (100% Simple)
• All development tools (MCP server, LSP, debugger - all in Simple)

Available platforms:

• Linux x86_64 / ARM64
• macOS x86_64 / ARM64
• Windows x86_64 / ARM64

# Linux x86_64
wget https://github.com/simple-lang/simple/releases/download/v0.6.1/simple-0.6.1-linux-x86_64.tar.gz
tar -xzf simple-0.6.1-linux-x86_64.tar.gz
cd simple-0.6.1
export PATH="$PWD/bin:$PATH"
simple --version

# macOS ARM64 (Apple Silicon)
curl -LO https://github.com/simple-lang/simple/releases/download/v0.6.1/simple-0.6.1-darwin-aarch64.tar.gz
tar -xzf simple-0.6.1-darwin-aarch64.tar.gz
cd simple-0.6.1
export PATH="$PWD/bin:$PATH"
simple --version

# Windows x86_64 (PowerShell)
Invoke-WebRequest -Uri https://github.com/simple-lang/simple/releases/download/v0.6.1/simple-0.6.1-windows-x86_64.zip -OutFile simple.zip
Expand-Archive simple.zip
cd simple-0.6.1
$env:PATH = "$PWD\bin;$env:PATH"
simple --version

Note: The runtime is pre-compiled for performance, but the entire language implementation (compiler, stdlib, tools) is in Simple source code that you can read and modify!

Only needed if you want to modify the runtime:

git clone https://github.com/simple-lang/simple.git
cd simple

# Linux bootstrap verification
scripts/bootstrap/bootstrap-from-scratch.sh --output=bootstrap

Direct commands behind the wrapper:

src/compiler_rust/target/bootstrap/simple --version
bin/simple build bootstrap
sha256sum bootstrap/simple_stage2 bootstrap/simple_stage3

See doc/08_tracking/build/bootstrap_multi_platform.md and doc/03_plan/pure_simple_bootstrap.plan.md for the current bootstrap flow.

simple build --release --features=vulkan

# hello.spl
>>> fn main() -> i64:
...     0  # Entry point, returns exit code

# Run it
simple hello.spl
echo $?  # Prints: 0

The simple command works like Python:

Usage:
  simple                      Start interactive REPL
  simple <file.spl>           Run source file
  simple <file.smf>           Run compiled binary
  simple -c "code"            Run code string; statement snippets print only program output
  simple compile <src> [-o <out>]  Compile to SMF
  simple watch <file.spl>     Watch and auto-recompile

Build System (Self-Hosting):
  simple build                Build the project (debug)
  simple build --release      Release build (optimized)
  simple build --bootstrap    Bootstrap build (minimal 9.3MB)
  simple build test           Run all tests
  simple build coverage       Generate coverage reports
  simple build lint           Run linter (clippy)
  simple build fmt            Format code (rustfmt)
  simple build check          Run all quality checks
  simple build clean          Clean build artifacts
  simple build --help         Show all build options

Options:
  -h, --help     Show help
  -v, --version  Show version
  -c <code>      Run code string
  --gc-log       Enable verbose GC logging
  --gc=off       Disable garbage collection

# Interactive REPL
simple
>>> 1 + 2
3
>>> x = 10
>>> x * 5
50
>>> exit

# Run a program
echo "main = 42" > hello.spl
simple hello.spl
echo $?  # Exit code: 42

# Compile to binary
simple compile hello.spl
simple hello.smf  # Run the compiled binary

# Watch mode (auto-recompile on changes)
simple watch app.spl

# Variables - immutable by default, mutable with var
>>> x = 10
>>> x
10
>>> var y = 20
>>> y
20
>>> PI = 3.14159
>>> PI
3.14159

# Type inference works automatically
>>> count = 100
>>> count
100

# Basic types inferred
>>> a = 42
>>> a
42
>>> pi = 3.14159
>>> flag = true
>>> flag
true

# String interpolation default
>>> name = "world"
>>> msg = "Hello, {name}!"
>>> print msg
Hello, world!

# If/else with indentation
>>> var x = 5
>>> if x > 0:
...     print "positive"
... elif x < 0:
...     print "negative"
... else:
...     print "zero"
positive

# Loops
>>> for i in 0..3:
...     print i
0
1
2

>>> while x > 3:
...     x = x - 1
>>> x
3

>>> fn add(a: i64, b: i64) -> i64:
...     a + b  # Implicit return

>>> fn greet(greeting: text):
...     print "Hello, {greeting}!"

# Function calls
>>> sum = add(1, 2)
>>> sum
3
>>> greet("Alice")
Hello, Alice!

# Lambdas with backslash
>>> double = \x: x * 2
>>> nums = [1, 2, 3, 4, 5]
>>> evens = nums.filter(\x: x % 2 == 0)
>>> evens
[2, 4]

# Structs (value types)
struct Point:
    x: f64
    y: f64

p = Point(x: 1.0, y: 2.0)

# Classes (reference types)
class Person:
    name: text
    age: i64

    fn greet():
        print "Hi, {self.name}!"

alice = Person(name: "Alice", age: 30)
alice.greet()

# Arrays - short form (no val)
>>> nums = [1, 2, 3, 4, 5]
>>> first = nums[0]
>>> first
1

# Collection methods
>>> count = nums.len()
>>> count
5

# Dictionary (short form)
>>> scores = {"alice": 100, "bob": 85}
>>> alice_score = scores["alice"]
>>> alice_score
100

# Filter with lambda
>>> odds = nums.filter(\x: x % 2 == 1)
>>> odds
[1, 3, 5]
>>> big_nums = nums.filter(\x: x > 3)
>>> big_nums
[4, 5]

# Tuples
>>> pair = (1, "hello")
>>> num = pair.0
>>> num
1
>>> msg = pair.1
>>> msg
"hello"

# List comprehensions
>>> squared = [x * x for x in 0..5]
>>> squared
[0, 1, 4, 9, 16]
>>> evens = [x for x in nums if x % 2 == 0]
>>> evens
[2, 4]

Type-safe units prevent mixing incompatible values:

# Define measurement unit families with postfix syntax
unit length(base: f64):
    mm = 0.001, cm = 0.01, m = 1.0, km = 1000.0

unit velocity(base: f64) = length / time:
    mps = 1.0, kmph = 0.2777777777777778, mph = 0.44704
# The standards-backed catalog records km/h canonically as kilometre / hour
# with exact factor 5/18 relative to m/s.

# Define nominal wrappers with postfix syntax
newunit UserId: i64 as uid
newunit OrderId: i64 as oid

# Usage with postfix literals
height = 175_cm              # Length type
width = 10_cm + 5_mm         # Auto-converts to same base
speed = 200_kmph             # Velocity type
distance = 42_km             # Length type

# Type safety - compile error:
# bad = height + speed       # Error: can't add Length + Velocity

# Semantic IDs prevent mix-ups
user = 42_uid                # UserId
order = 100_oid              # OrderId
# wrong: UserId = 100_oid    # Error: OrderId ≠ UserId

# Computed units
travel_time = distance / speed    # Returns Time type
print("ETA: {travel_time.to_min()} minutes")

enum Shape:
    Circle(radius: f64)
    Rectangle(width: f64, height: f64)
    Square(side: f64)
    Triangle(base: f64, height: f64)

# Pattern matching with case syntax
fn area(s: Shape) -> f64:
    match s:
        case Circle(r):
            3.14159 * r * r  # Implicit return
        case Rectangle(w, h):
            w * h
        case Square(side):
            side * side
        case Triangle(b, h):
            0.5 * b * h

# Preferred arrow syntax (shorter)
fn perimeter(s: Shape) -> f64:
    match s:
        | Circle(r) -> 2.0 * 3.14159 * r
        | Rectangle(w, h) -> 2.0 * (w + h)
        | Square(side) -> 4.0 * side
        | Triangle(a, b, c) -> a + b + c

# Pattern matching with nil (not None)
fn get_radius(opt: Option<f64>) -> f64:
    match opt:
        | Some(r) -> r
        | nil -> 0.0  # Use nil instead of None

Simple macros are contract-first and LL(1) parseable - the IDE can provide autocomplete without expanding the macro:

# Macro declares what it introduces in the contract header
macro define_counter(NAME: Str const) -> (
  returns result: (init: Int, step: Int),
  intro counter_fn: enclosing.class.fn "{NAME}Counter"(start: Int) -> Int
):
  const_eval:
    const init = 0
    const step = 1

  emit counter_fn:
    fn "{NAME}Counter"(start: Int) -> Int:
      start + step

# Usage - IDE knows about UserCounter before expansion
class Demo:
  define_counter!("User")

  fn run() -> Int:
    self.UserCounter(10)  # Autocomplete works!

Built-in macros:

# Print with formatting
println!("Hello, {name}!")           # Print with newline
print!("Value: {x}")                 # Print without newline

# Debug output with source location
dbg!(expression)                     # Prints: [file:line] expression = value

# Assertions
assert!(condition)                   # Panic if false
assert_eq!(a, b)                     # Panic if a != b
assert_ne!(a, b)                     # Panic if a == b

# Collections
nums = vec![1, 2, 3, 4, 5]           # Create vector
formatted = format!("x={x}")         # Format string without printing

# Panic with message
panic!("Something went wrong: {err}")

Const-unrolled macro (generate multiple functions):

# Generate accessor functions for each axis
macro gen_axes(BASE: Str const, N: Int const) -> (
  intro axes:
    for i in 0 .. N:
      enclosing.class.fn "{BASE}{i}"(v: Vec[N]) -> Int
):
  emit axes:
    for i in 0 .. N:
      fn "{BASE}{i}"(v: Vec[N]) -> Int:
        v[i]

# Usage: generates x(), y(), z() accessors
class Point3D:
  gen_axes!("axis_", 3)  # Creates axis_0, axis_1, axis_2

Predicate-based pointcuts with compile-time weaving as the default execution model:

# Before advice — runs before matching functions
on pc{ execution(* handle_request(..)) } use log_entry before priority 10

# After advice — runs after successful return
on pc{ execution(* save(..)) & attr(audited) } use audit_write after_success priority 20

# Around advice — wraps function with proceed() contract
on pc{ within(services.*) } use trace_around around priority 50

# Architecture rules — enforce layer dependencies at compile time
forbid pc{ within(hal.*) } "HAL cannot depend on services"
allow  pc{ within(services.*) } "Services can use HAL"

Supported selectors: execution(*), within(*), attr(*) with & (AND), | (OR), ! (NOT) operators. Advice kinds: before, after_success, after_error, around (proceed exactly-once). Ordering: priority (descending) > specificity > lexicographic name. Zero overhead: no weaving metadata when no aspects are defined. Runtime interception: scoped, opt-in only, disabled in release builds.

See AOP Support Matrix for the full contract.

Simple Data Notation - a minimal, token-efficient format for config files:

# app.sdn - Application configuration
app:
    name: MyService
    version: 2.1.0

server:
    host: 0.0.0.0
    port: 8080
    workers: 4

# Inline arrays and dicts
features = [auth, logging, metrics]
database = {driver: postgres, host: localhost, port: 5432}

# Named tables - compact tabular data
rate_limits |endpoint, requests, window|
    /api/login, 5, 60
    /api/search, 100, 60
    /api/upload, 10, 300

Load SDN in Simple:

config = sdn::load("app.sdn")
print("Server port: {config.server.port}")

Executable examples are part of the maintained test surface. Simple supports both demonstration blocks and verified sdoctest blocks, with sdoctest intended for examples that must run and match output.

>>> factorial(5)
120
>>> factorial(0)
1

## Stack data structure with LIFO semantics
struct Stack:
    items: [i64]

var s = Stack(items: [])
s.items.push(1)
s.items.push(2)
print s.items.len()  # 2

Run SDoctest examples:

simple test --sdoctest README.md      # Run verified examples in Markdown/docs
simple test --sdoctest src/math.spl   # Run file-local doctest examples
simple test --sdoctest --tag slow     # Filter by tag

--doctest is still accepted as a compatibility alias, but --sdoctest is the clearer name for the implemented path.

# The -> operator calls a method and assigns result back
var data = load_data()
data->normalize()        # data = data.normalize()
data->filter(min: 0)     # data = data.filter(min: 0)

# Chaining
data->normalize()->filter(min: 0)->save("out.txt")

import std.gpu

# GPU kernel style 1: #[gpu] with explicit bounds check
#[gpu]
fn vector_add_kernel(a: []f32, b: []f32, result: []f32):
    idx = gpu.global_id(0)           # Global thread index
    if idx < len(result):
        result[idx] = a[idx] + b[idx]

# GPU kernel style 2: @simd with auto bounds handling
@simd
fn vector_scale(data: []f32, scale: f32):
    val i = this.index()             # Global linear index (same as gpu.global_id())
    data[i] = data[i] * scale        # Bounds auto-handled

# Host function - runs on CPU
fn main():
    device = gpu.Device()

    # Allocate and upload data
    a = [1.0, 2.0, 3.0, 4.0]
    b = [5.0, 6.0, 7.0, 8.0]

    buf_a = device.alloc_buffer(a)
    buf_b = device.alloc_buffer(b)
    buf_result = device.alloc_buffer<f32>(4)

    # Launch kernel
    device.launch_1d(vector_add_kernel, [buf_a, buf_b, buf_result], 4)

    # Download results
    device.sync()
    result = device.download(buf_result)
    # result = [6.0, 8.0, 10.0, 12.0]

GPU Thread Indexers:

#[gpu]
fn matrix_multiply(A: []f32, B: []f32, C: []f32, N: u32):
    # Multi-dimensional indexing
    val row = gpu.global_id(0)       # First dimension
    val col = gpu.global_id(1)       # Second dimension

    # Thread group (workgroup) info
    val local_row = gpu.local_id(0)  # Index within workgroup
    val group_row = gpu.group_id(0)  # Workgroup index

    # Alternative @simd style
    # val(row, col) = this.index()  # Tuple for 2D
    # vallocal_idx = this.thread_index()
    # valgroup_idx = this.group_index()

    if row < N and col < N:
        var sum = 0.0_f32
        for k in 0..N:
            sum += A[row * N + k] * B[k * N + col]
        C[row * N + col] = sum

GPU Examples: See examples/gpu/vulkan/ for vector add, matrix multiply, reduction, and image blur.

Getting Started:

• Documentation Hub - Current entry point for the numbered doc tree
• Getting Started - Project setup and first steps
• Syntax Quick Reference - Canonical public syntax cheat sheet
• Testing Guide - Testing workflow and command surface

Language Reference:

• Syntax Guide - Surface syntax and examples
• Type System Guide - Types, mutability, and usage
• Module System Guide - Imports, packages, and layout
• Standard Library Guide - Stdlib organization and usage

GPU Computing:

• Deep Learning Guide - Pure Simple, model-oriented, and training flows
• GPU Programming Guide - Backend and kernel-oriented GPU usage
• GPU API - API-level GPU reference
• LLVM Backend Architecture - Backend implementation details

Development:

• Build Guide - Building Simple and common workflows
• Testing Guide - Test runner behavior and flags
• Mock Policy Guide - System test mock ban and test level enforcement
• Coverage Guide - Coverage, SDoctest, and enforcement
• MCP Tooling Guide - MCP registration and usage

Advanced Features:

• Macro System - Executable macro spec and status
• AOP Support Matrix - Supported selectors, advice kinds, backends, and error codes
• SDN Format - Note/SDN storage and indexing format
• SDoctest - Documentation testing and verified examples
• Feature Documentation - Generated feature-doc artifact format

Simple ships multiple deep learning examples across pure-Simple, model-training, and GPU-oriented flows:

Pure Simple Neural Networks:

# XOR neural network training
bin/simple examples/pure_nn/xor_training_example.spl

# Linear regression (learns y = 2x + 1)
bin/simple examples/pure_nn/simple_regression.spl

# Iris flower classification
bin/simple examples/pure_nn/iris_classification.spl

MedGemma Korean Fine-Tuning:

# Progressive LoRA training to prevent catastrophic forgetting
bin/simple examples/medgemma_korean/run_all.spl

CUDA Programming:

# Direct CUDA C API - multi-GPU, streams, events
bin/simple examples/cuda/basic.spl

See Deep Learning Guide for current documentation.

The examples/ directory contains additional working examples:

Run an example:

bin/simple examples/cli_demo.spl

Feature documentation is auto-generated from BDD spec tests. Each spec defines feature metadata and executable assertions that verify the feature works correctly.

# simple/std_lib/test/features/infrastructure/lexer_spec.spl
import std.spec

feature "Lexer":
    """
    The lexer tokenizes Simple source code into tokens.
    Feature ID: #1
    Category: infrastructure
    """

    scenario "tokenizes keywords":
        given "source code with keywords"
        when "the lexer processes it"
        then "it produces keyword tokens"
        expect tokenize("fn main") to contain Token(Keyword, "fn")

    scenario "handles indentation":
        given "indented code blocks"
        when "the lexer processes it"
        then "it emits INDENT and DEDENT tokens"

Run feature tests:

# Run a specific feature spec
./target/debug/simple simple/std_lib/test/features/infrastructure/lexer_spec.spl

# Generate documentation from tests
./target/debug/simple simple/std_lib/test/features/generate_docs.spl

Generated docs land in the numbered documentation tree, primarily under doc/06_spec/, so the checked examples stay close to the current spec artifacts.

Simple’s current language references are split between the guide tree for user-facing explanations and the spec tree for executable or generated reference material.

Current Reference Documents:

• Syntax Quick Reference - Fast public-language reference
• Syntax Guide - User-facing language walkthrough
• Language Spec Index - Current generated spec index
• Syntax Spec - Spec artifact for syntax coverage
• Types Spec - Spec artifact for type-system coverage
• Modules Spec - Spec artifact for module-system coverage

Quick Grammar Reference:

# Top-level
program ::= statement*

# Statements
statement ::= function_def | class_def | struct_def | enum_def
            | import_stmt | export_stmt | expr_stmt

# Expressions (Pratt parser)
expr ::= literal | identifier | binary_op | unary_op
       | call | index | field_access | lambda
       | if_expr | match_expr | block

# Types
type ::= identifier | array_type | tuple_type | fn_type
       | optional_type | result_type | generic_type

# Literals
literal ::= integer | float | string | bool | array | dict | tuple

The current spec and guide material is organized under the numbered documentation tree:

Core Language:

• Syntax Spec - Syntax-oriented spec material
• Types Spec - Type-system spec material
• Data Structures Spec - Data-structure coverage
• Functions Spec - Functions and pattern matching
• Traits Spec - Traits and implementations
• Memory Spec - Ownership and borrowing
• Modules Spec - Import/export system

Advanced Features:

• Concurrency Spec - Async and concurrency behavior
• Metaprogramming Spec - Macros and decorators
• Macro Spec - Macro-specific executable coverage
• Capability Effects - Capability/effect system
• Standard Library Guide - Stdlib structure and usage
• SFFI Guide - Interop guidance

Testing & Tooling:

• Testing Guide - Test runner and matchers
• Coverage Guide - Coverage and SDoctest enforcement
• Lint Guide - Lint rules and workflow
• MCP Guide - MCP workflow and registration

GPU & Platform:

• GPU Programming Guide - GPU usage
• Deep Learning Guide - Model-oriented examples
• Baremetal Guide - Platform and baremetal flows

See doc/README.md, doc/06_spec/README.md, and doc/07_guide/README.md for the current documentation entry points.

simple/
├── bin/                      # CLI entry points
│   ├── simple               # Main CLI (shell wrapper)
│   └── release/             # Pre-built release binaries
│       └── simple           # Pre-built runtime (33 MB)
│
├── src/                      # Simple source code (100% Simple)
│   ├── app/                  # Applications
│   │   ├── cli/             # Main CLI dispatcher
│   │   ├── build/           # Self-hosting build system
│   │   ├── mcp/             # MCP server (Model Context Protocol)
│   │   ├── lsp/             # Language server protocol
│   │   ├── io/              # SFFI wrappers (file, process, etc.)
│   │   └── ...              # 50+ tool modules
│   ├── lib/                  # Libraries
│   │   ├── database/        # Unified database (BugDB, TestDB, etc.)
│   │   └── pure/            # Pure Simple DL (tensor, autograd, nn)
│   ├── std/                  # Standard library
│   │   ├── src/             # Library source
│   │   └── test/            # Library tests
│   └── compiler/             # Compiler infrastructure
│       ├── backend/         # Code generation
│       ├── inference/       # Type inference
│       └── parser/          # Parser and treesitter
│
├── examples/                 # Example programs
│   ├── pure_nn/             # Deep learning examples
│   └── gpu/vulkan/          # GPU computing examples
│
├── test/                     # Test suites
│   ├── integration/         # Integration tests
│   ├── system/              # System tests
│   └── intensive/           # Intensive feature tests
│
├── doc/                      # Documentation
│   ├── spec/                # Language specifications
│   ├── guide/               # User guides
│   ├── design/              # Design documents
│   └── report/              # Session reports
│
└── verification/             # Lean 4 formal verification

# Debug build
simple build

# Release build
simple build --release

# With GPU support
simple build --release --features=vulkan

# Bootstrap build (minimal 9.3MB)
simple build --bootstrap

Full-suite snapshot (2026-02-14): 4,067/4,067 passing

Simple uses a broad test strategy spanning spec tests, SDoctest, coverage, and system lanes. The counts below are from the linked 2026-02-14 report:

# All tests (4,067 tests in 17.4 seconds)
simple test

# Run specific test file
simple test path/to/spec.spl

# With verbose output
simple test --verbose

# Coverage reports
simple build coverage

Test Coverage:

• Core interpreter: 227 tests
• Compiler: 306 tests
• Standard library: 428 tests
• Applications: 142 tests
• Libraries (ML, Physics, Game): 185 tests
• Integration & Coverage: 2,779 tests

Performance:

• Total execution: 17.4 seconds
• Average per test: 4.3ms
• All tests deterministic and fast

See doc/09_report/session/full_test_suite_results_2026-02-14.md for detailed test analysis.

# Check before commit (fmt + lint + test)
simple build check

# Full check (includes coverage + duplication)
simple build check --full

# Format code
simple build fmt

# Lint
simple build lint

Simple ships with MCP servers, LSP servers, and Claude Code plugins — all written in Simple.

The Simple MCP server exposes repo-native tools for code diagnostics, VCS, build, test, debug, and related workflows. For current registration details, use the repo scripts and guide docs rather than relying on hardcoded counts here.

# From a repo checkout — register with Claude Code
claude mcp add simple-mcp -- \
  /absolute/path/to/simple/bin/simple \
  /absolute/path/to/simple/src/app/mcp/main.spl

# Or use the project .mcp.json (auto-detected by Claude Code)
sh config/mcp/install.shs

The simple-mcp Claude plugin is a repo-checkout plugin. Install it from a Simple repository checkout; it is not a standalone portable runtime bundle.

claude plugin marketplace add tools/claude-plugin/marketplace
claude plugin install simple-mcp@simple-local

The plugin launches bin/simple_mcp_server from the repository root.

The Simple language server provides completions, hover, go-to-definition, diagnostics, and semantic tokens for .spl / .shs files.

# From a repo checkout
claude plugin marketplace add tools/claude-plugin/marketplace
claude plugin install simple-lsp@simple-local

Binary full path: bin/simple run src/app/lsp/main.spl

cd /path/to/simple

# 1. MCP server
sh config/mcp/install.shs

# 2. LSP plugin
claude plugin marketplace add tools/claude-plugin/marketplace
claude plugin install simple-lsp@simple-local

Once the MCP server and LSP plugin are installed, try these prompts in Claude Code:

> "Run the linter on src/app/cli/main.spl and fix any warnings"

> "Show me all unused variables in the compiler frontend"

> "Run the unit tests for the SDN parser"

> "Build the project in release mode and show the result"

> "What does the function `parse_expression` in the parser do?"

> "Find all TODO items in the codebase"

> "Check the doc coverage for the standard library"

> "Debug why test/unit/lib/common/value_spec.spl is failing"

Full-featured extension with Tree-sitter highlighting, LSP integration, and math block support.

cd src/app/vscode_extension
npm install && npm run compile && npm run package
code --install-extension simple-language-0.1.0.vsix

Key features:

• Semantic syntax highlighting (Tree-sitter powered)
• LSP: completions, hover, go-to-definition, diagnostics
• Math block highlighting for m{}, loss{}, nograd{} with nested brace support
• Test CodeLens: "Run Test/File/Doctest" gutter arrows on describe/it/context/sdoctest blocks
• AI-powered completions and chat (requires GitHub Copilot)

See src/app/vscode_extension/README.md for full documentation.

-- lazy.nvim
{ "nicholasgasior/simple.nvim", ft = "simple", opts = {} }

-- Or from project checkout
vim.opt.rtp:prepend("/path/to/simple/src/app/nvim_plugin")
require("simple").setup()

Key features:

• LSP integration with auto-detection
• Math block conceal with inline Unicode preview (frac(1,2) -> (1)/(2), alpha -> α, sqrt(x) -> √(x))
• Test lens: "Run" virtual text beside test blocks
• Tree-sitter queries (highlights, folds, text objects, injections)
• Brief view (fold to signatures)

See src/app/nvim_plugin/README.md for full documentation.

MCP servers, CMM language server, and CLI tools for Lauterbach TRACE32 debuggers. See examples/10_tooling/trace32_tools/README.md for full documentation.

The repo-managed container flow is headless and uses t32mciserver. It does not ship bundled TRACE32 GUI compatibility libraries; vendor runtime files must come from your local /opt/t32 installation.

Primary lifecycle wrapper:

scripts/t32q.shs build
scripts/t32q.shs on
scripts/t32q.shs wait
scripts/t32q.shs ping
scripts/t32q.shs reopen
scripts/t32q.shs off

GUI container reopen path:

scripts/t32q.shs gui-on
scripts/t32q.shs gui-reopen
scripts/t32q.shs off

gui-on uses the Docker/Podman TRACE32 GUI path with host X11 forwarding, so it requires a real host X11 session (DISPLAY, /tmp/.X11-unix, and usually XAUTHORITY). For quick diagnostics use:

scripts/t32q.shs doctor

Hello-world firmware smoke:

scripts/t32_semihost_hello.shs --board stm32wb
scripts/t32_semihost_hello.shs --board stm32h7
scripts/t32_semihost_hello.shs --board stm32wb --build-only

These TRACE32 MCP servers are not installed by the default project MCP setup. Register them manually only if you actively use TRACE32 tooling.

cd /path/to/simple

# T32 MCP — controls live TRACE32 debug sessions (23 tools)
claude mcp add t32-mcp -- \
  /absolute/path/to/simple/bin/simple \
  /absolute/path/to/simple/examples/10_tooling/trace32_tools/t32_mcp/main.spl

# T32 LSP MCP — CMM script analysis, no hardware needed (6 tools)
claude mcp add t32-lsp-mcp -- \
  /absolute/path/to/simple/bin/simple \
  /absolute/path/to/simple/examples/10_tooling/trace32_tools/t32_lsp_mcp/main.spl

Binary full paths:

• T32 MCP: bin/simple run examples/10_tooling/trace32_tools/t32_mcp/main.spl
• T32 LSP MCP: bin/simple run examples/10_tooling/trace32_tools/t32_lsp_mcp/main.spl

claude plugin marketplace add tools/claude-plugin/marketplace
claude plugin install cmm-lsp@simple-local

Binary full path: bin/simple run examples/10_tooling/trace32_tools/cmm_lsp/mod.spl --lsp

> "Parse this CMM script and check for errors: config/t32/stm32h7_gdb_start.cmm"

> "Connect to TRACE32 on localhost:20000 and read the CPU registers"

> "Show me all labels and macros defined in my CMM script"

> "Convert this GUI PRACTICE script to CLI batch mode"

> "Check if my CMM script has any undefined macros or unreachable code"

> "Set a breakpoint at main, run to it, and show local variables"

> "What TRACE32 commands are available for memory access?"

> "Auto-complete suggestions for 'Data.LOAD' in my CMM script"

See CLAUDE.md for development guidelines and AGENTS.md for AI agent instructions.

Documentation Structure:

• Specifications go in doc/06_spec/ (what the language supports)
• Guides go in doc/07_guide/ (how to use features)
• Research goes in doc/01_research/ (why/how decisions were made)
• Plans go in doc/03_plan/ (implementation roadmaps)
• Reports go in doc/09_report/ (session summaries and completion reports)

Apache License 2.0. See LICENSE.

Bundled third-party runtime components and redistribution notices are listed in THIRD_PARTY_NOTICES.md.

Release packages also include THIRD_PARTY_NOTICES.md.

Official Documentation:

• Documentation Hub - Entry point for the numbered docs tree
• Language Specification - Current spec index
• User Guides - Practical tutorials

Quick References:

• Syntax Quick Reference
• Type System Guide
• GPU Computing Guide

Development:

• Architecture Overview
• Feature Documentation
• Implementation Plans