Configuration

JAPL projects use a japl.toml manifest file at the project root. This file declares project metadata, dependencies, and build settings.

Status: Planned. The configuration system is currently minimal. The fields documented here represent the planned manifest format. The compiler does not yet read japl.toml — it operates on individual source files passed via the CLI.

File Location

The japl.toml file must be placed at the root of your project directory:

my-project/
  japl.toml
  src/
    main.japl
    lib.japl
  test/
    main_test.japl

[package] Section

The [package] section declares project metadata.

[package]
name = "my-project"
version = "0.1.0"
entry = "src/main.japl"

Fields

name

Type: String (required)

The project name. Must be a valid JAPL identifier using lowercase letters, digits, and hyphens. Used as the default module name and package identifier.

name = "http-server"

version

Type: String (required)

The project version following semantic versioning (major.minor.patch).

version = "1.2.3"

entry

Type: String (required)

The path to the main source file, relative to the project root. This is the entry point the compiler uses when building or running the project.

entry = "src/main.japl"

[dependencies] Section

Planned. Dependency management is not yet implemented.

The [dependencies] section will declare external package dependencies.

[dependencies]
json = "1.0"
http = "0.5"

[dev-dependencies] Section

Planned. Dev dependencies will be available only during testing and benchmarking.

[dev-dependencies]
test-helpers = "0.2"

[build] Section

Planned. Build configuration options for controlling compiler behavior.

[build]
target = "native"        # "native", "wasm", "wasm-wasi"
opt-level = 2            # 0 = debug, 1 = basic, 2 = full

Fields

target

Type: String (optional, default: "native")

The compilation target. Supported values:

opt-level

Type: Integer (optional, default: 0)

Optimization level. Higher values produce faster code but slower compilation.

[test] Section

Planned. Configuration for the built-in test runner.

[test]
parallel = true
timeout = 30000          # milliseconds per test

[node] Section

Planned. Configuration for distributed JAPL nodes.

[node]
name = "web-1"
listen = "0.0.0.0:9000"
cookie-env = "CLUSTER_COOKIE"

Example japl.toml

A complete example showing all planned sections:

[package]
name = "my-web-service"
version = "0.1.0"
entry = "src/main.japl"

[dependencies]
http = "1.0"
json = "1.2"
db = "0.8"

[dev-dependencies]
test-helpers = "0.2"

[build]
target = "native"
opt-level = 2

[test]
parallel = true
timeout = 30000

[node]
name = "web-1"
listen = "0.0.0.0:9000"
cookie-env = "CLUSTER_COOKIE"

Current Limitations

The japl.toml configuration system is not yet implemented in the compiler. Currently:

• The compiler operates on individual .japl files passed as CLI arguments.
• There is no dependency resolution or package management.
• Build targets are controlled via the WASM codegen pipeline, not through configuration.
• Module resolution uses file system conventions rather than manifest declarations.

These features are planned for future releases. The manifest format documented here is subject to change.