Hecate Plugin SDK

The contract between the Hecate daemon and plugins.

Plugins are OTP applications that load into the daemon VM. The SDK provides:

Platform dependencies — pinned versions, one {hecate_sdk, "~> 0.5"} dep
Plugin behaviour — hecate_plugin callbacks the daemon calls
Observability — structured JSON logging, metrics, health reporting (auto-wired)
Helpers — paths, store setup, cowboy routes, WebSocket, validation, scheduling, rate limiting, file I/O

Quick Start

%% rebar.config
{deps, [
    {hecate_sdk, "~> 0.5"}
]}.

Implement the hecate_plugin behaviour:

-module(my_plugin).
-behaviour(hecate_plugin).
-include_lib("hecate_sdk/include/hecate_plugin.hrl").

-export([init/1, routes/0, store_config/0, static_dir/0, manifest/0]).

init(_Config) ->
    {ok, #{}}.

routes() ->
    [{"/items", my_plugin_items_api, []},
     {"/items/:id", my_plugin_item_api, []}].

store_config() ->
    #hecate_store_config{
        store_id = my_items_store,
        dir_name = "items",
        description = "My plugin items store"
    }.

static_dir() ->
    code:priv_dir(my_plugin) ++ "/static".

manifest() ->
    #{
        name => <<"my-plugin">>,
        version => <<"0.1.0">>,
        min_sdk_version => <<"0.1.0">>,
        description => <<"My awesome plugin">>,
        native_capabilities => #{
            notifications => true
        }
    }.

What You Get

Platform Dependencies (all come transitively)

Concern	Library
Event Sourcing	evoq
Event Store	reckon_db + reckon_gater + reckon_evoq
HTTP/WebSocket	cowboy
Read Models	esqlite (SQLite)
Mesh	macula
HTTP Client	hackney
Time	qdate
AI/ML	faber_tweann + faber_neuroevolution
Protobuf	gpb (optional)

Plus OTP builtins: json, ets, pg, logger, crypto, calendar, mnesia.

SDK Helpers

Module	Purpose
`hecate_plugin`	Behaviour definition
`hecate_plugin_metrics`	Counters + gauges (lock-free)
`hecate_plugin_telemetry`	Auto-attach to evoq/reckon-db events
`hecate_plugin_logger`	JSON log formatter for OTP logger
`hecate_plugin_paths`	Standard directory layout
`hecate_plugin_store`	ReckonDB store creation + dispatch
`hecate_plugin_cowboy`	Route prefixing + static serving
`hecate_plugin_ws`	WebSocket upgrade + JSON framing
`hecate_plugin_validate`	Input validation rules
`hecate_plugin_scheduler`	Cron-like recurring tasks
`hecate_plugin_ratelimit`	Token bucket rate limiter
`hecate_plugin_files`	Upload/download helpers
`hecate_plugin_api`	JSON request/response utilities for Cowboy handlers
`hecate_plugin_routes`	Route discovery from OTP app metadata
`hecate_plugin_llm`	Capability-based LLM model selection
`hecate_plugin_codegen`	Code generation for plugin scaffolding (plugin, division, desk, integration)

Frontend

Plugin frontends are static assets (HTML/JS/CSS) served by the daemon at /plugin/{name}/. Build with any framework (SvelteKit, React, plain HTML) — just output to priv/static/.

Your frontend talks to the backend via:

REST: fetch('/plugin/{name}/api/...')
WebSocket: new WebSocket('ws://localhost:4444/plugin/{name}/ws')

For native OS access (file pickers, notifications, clipboard), use the Tauri bridge:

window.__hecate_bridge.request({ action: &#39;file-picker&#39;, options: {} })

License

Apache-2.0