Environment Reference

An environment is the runtime or deployment lane used when resolving variables. Common examples are dev, stage, and prod.

Declaring Environments

Workspace environments are declared in rototo-workspace.toml:

[environments]
values = ["dev", "stage", "prod"]

Rules:

• at least one environment is required;
• names must be strings;
• names must be unique;
• _ is reserved and must not be declared here.

Variable Environment Blocks

Variables select values through [variable.env] blocks:

[variable.env._]
value = "standard"

[variable.env.dev]
value = "small"

[variable.env.prod]
value = "large"

Every variable must define [variable.env._]. That block is the fallback when the requested environment has no variable-specific block.

Named environment blocks must match environments declared in the workspace manifest.

Resolution Behavior

When resolving a variable for an environment:

1. rototo checks that the requested environment is declared by the workspace.
2. rototo uses [variable.env.<environment>] if it exists.
3. Otherwise, rototo uses [variable.env._].
4. Rules in the selected block are evaluated in order.
5. The first matching rule selects its value.
6. If no rule matches, the block's value is selected.

The _ fallback is per variable. It does not make _ a valid requested environment.

Unknown Environments

Resolving a variable for an environment not declared in the workspace manifest fails before fallback selection.

This is deliberate. A misspelled environment such as prd should not silently use production or default behavior.

Example

schema_version = 1

[variable]
description = "Maximum number of tokens the summarizer can emit"
type = "int"

[variable.values]
small = 500
standard = 1000
large = 2000

[variable.env._]
value = "standard"

[variable.env.dev]
value = "small"

[variable.env.prod]
value = "large"

Resolution results:

dev   -> small    -> 500
prod  -> large    -> 2000
stage -> standard -> 1000, if stage has no block and is declared
prd   -> error, if prd is not declared