Repository F# setup

open System
open System.IO
open System.Threading
open System.Threading.Tasks
open Axial
open Axial.Layers
open Axial.Console
open Axial.FileSystem
open Axial.Hosting
open Axial.Hosting.Browser
open Axial.Hosting.Node
open Axial.PlatformService
open Axial.State
open Axial.Telemetry
open Axial.Telemetry.JavaScript

Platform services

Platform services expose common host capabilities to Flow with cancellation, replaceable implementations, and typed errors where callers can recover. They are supporting parts of Axial Core rather than separate documentation contexts.

Higher-level libraries build their own programming models on top of Axial and these capabilities. Axial.Process composes external commands and streams. Axial.HttpClient models HTTP requests, responses, and reliability. Each has its own guides and API reference.

Service	Wraps	Axial API
Clock	`DateTimeOffset.UtcNow`	Current time and derived Unix-time readers
Logging	Host logging	Structured messages and exception-preserving logging
Randomness and GUIDs	`System.Random`, `Guid.NewGuid()`	Explicit random values, byte generation, and GUID creation
Environment variables	`Environment.GetEnvironmentVariable`	Required and parsed reads with `EnvironmentVariableError`
Console	`System.Console`	Standard streams, redirection, and terminal control
File system	`System.IO.File` and `Directory`	File and directory operations with `FileSystemError`

open Axial
open Axial.Console

Axial

Console

A workflow declares the capability it needs:

let greet name : Flow<#IHasConsole, Never, unit> =
    Console.writeLine $"Hello, {name}."

greet: 'a -> Flow<'b,Never,unit>

name: 'a

Axial.Flow`3

Represents a cold workflow that reads an environment, returns a typed result, and is executed explicitly through one of its execution members such as ToTask, ToAsync, or RunSynchronously. The type of the environment dependency. The type of the failure value. The type of the success value.

Axial.Console.IHasConsole

Declares that an environment supplies the console service. Implement this on the environment supplied at the host edge. A workflow that reads or writes the console constrains its environment with 'env :> IHasConsole.

Axial.Never

Represents an error channel that cannot occur.

unit

The type 'unit', which has only one value "()". This value is special and always uses the representation 'null'. Basic Types

Axial.Console.ConsoleModule

writeLine: string -> Flow<'env,'error,unit>

The host supplies the live implementation at the edge. Tests supply a recording or in-memory implementation of the same contract.

In this section

Platform-service bundle — clock, logging, randomness, GUIDs, and environment variables.
Console — standard streams, redirection, and terminal control.
File system — files, directories, paths, and typed failures.
Using existing services — compose BaseRuntime with application dependencies.

Telemetry instruments the runtime rather than defining a workflow dependency. Hosting supplies environments and application lifecycle integration.

Platform services

In this section

Overview

Docs

API Reference