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Configuration

Aether’s behavior can be tuned through environment variables (set before launch) and runtime built-in calls (called from .ae code).

Environment variables

Variable	Default	Description
AETHER_IO_WORKERS	(unset)	Enable the I/O thread pool with this many worker threads. When unset, http_get, sleep, read_file, write_file, and http_post run synchronously. When set, each call returns a Promise and runs on a worker thread.
AETHER_HTTP_TIMEOUT	30	Default request timeout in seconds for http_get and http_post.
AETHER_HTTP_USER_AGENT	aether/0.1	Default User-Agent header for HTTP requests.
AETHER_EVENT_LOOP_TIMEOUT	(none)	Default timeout in seconds for event_loop() calls with no argument. When unset, event_loop() runs until the queue is empty. Used with .then() / on_ready() callback-based async.
AETHER_QUEUE_LIMIT	1024	Maximum pending .then() / on_ready() callbacks that can be queued at once. Throws when this limit is reached.
AETHER_CALL_DEPTH	100	Maximum call stack depth before a StackOverflow error is raised.
HOME	OS default	REPL history is saved to $HOME/.aether_history. History is disabled for the session if HOME is unset.

Examples

# Enable 4-worker I/O pool
AETHER_IO_WORKERS=4 aether script.ae

# Limit event_loop to 30s, cap queue at 500
AETHER_EVENT_LOOP_TIMEOUT=30 AETHER_QUEUE_LIMIT=500 aether server.ae

# Custom HTTP timeout and user-agent
AETHER_HTTP_TIMEOUT=10 AETHER_HTTP_USER_AGENT="mybot/1.0" aether scraper.ae

Runtime built-ins

These are called from inside your .ae program and take effect immediately.

set_workers(n)

Enables (or replaces) the I/O thread pool with n workers. Any previously submitted tasks complete on the old pool before it shuts down.

set_workers(4)
let p = sleep(0.1)   // now runs on the pool
await p

set_queue_limit(n)

Caps the event loop queue at n pending callbacks. Overrides AETHER_QUEUE_LIMIT.

set_queue_limit(100)

set_task_timeout(secs) / set_task_timeout(null)

Sets a per-task deadline for on_ready() callbacks. Callbacks that don’t resolve within secs seconds are silently dropped. Pass null to remove the deadline.

set_task_timeout(10)    // each callback must complete within 10s
set_task_timeout(null)  // remove deadline

Per-request HTTP options

http_get and http_post accept an optional config dict as their last argument, overriding env-var defaults for that single request:

let data = http_get("https://slow.api.example.com/", {timeout: 60})
let resp = http_post("https://api.example.com/", payload, {
    timeout: 10,
    user_agent: "myapp/2.0"
})

Key	Type	Overrides
timeout	int (seconds)	AETHER_HTTP_TIMEOUT
user_agent	string	AETHER_HTTP_USER_AGENT