RapidForge supports mruby as a built-in script runtime for webhooks, periodic tasks, and on-fail scripts. Choose mruby when you want Ruby syntax without installing Ruby on the host machine.
The bundled runtime includes JSON support and HTTP helpers backed by mruby-curl. RapidForge starts every mRuby script with a small compatibility layer because this runtime does not expose Ruby's usual ENV or require.
Accessing Environment Variables
Use the env helper to read values injected by RapidForge:
payload = env("PAYLOAD_DATA")
token = env("CRED_API_TOKEN")
All injected values are also available in the RAPIDFORGE_ENV hash:
RAPIDFORGE_ENV.each do |key, value|
puts "#{key}=#{value}"
end
JSON
Use JSON.parse and JSON.generate for JSON work:
data = JSON.parse(env("PAYLOAD_DATA") || "{}")
puts JSON.generate({ ok: true, received: data })
HTTP Helpers
All HTTP helpers return two values: response body and HTTP status code.
body, status = http_get(
"https://httpbin.org/get",
{ "User-Agent" => "rapidforge/mruby" }
)
payload = JSON.generate({ hello: "world" })
body, status = http_post(
"https://httpbin.org/post",
payload,
{ "Content-Type" => "application/json" }
)
if status == 200 || status == 201
puts JSON.parse(body)["json"]["hello"]
else
STDERR.puts "request failed: #{status}"
end
Available helpers:
http_get(url, headers = {})http_post(url, body = "", headers = {})http_put(url, body = "", headers = {})http_patch(url, body = "", headers = {})http_delete(url, headers = {})
KV Helpers
mRuby scripts can use the RapidForge KV store directly:
kv_set("last-run", "2026-07-09T12:00:00Z")
value = kv_get("last-run")
puts "last run: #{value}"
keys = kv_list()
puts keys.join(",")
deleted = kv_del("last-run")
puts "deleted: #{deleted}"
Available helpers:
kv_get(key)returns the stored string value, ornilif the key does not exist.kv_set(key, value)returnstrueon success.kv_del(key)returnstrueif a key was deleted, orfalseif it was missing.kv_list()returns an array of stored keys.
Notes
RapidForge uses Ruby syntax highlighting for mruby in the editor. Autocomplete includes RapidForge helpers plus common mRuby snippets for classes, modules, hashes, arrays, JSON, HTTP, and KV usage.