diff --git a/examples/component/src/index.ts b/examples/component/src/index.ts
new file mode 100644
index 0000000000..a526600a20
--- /dev/null
+++ b/examples/component/src/index.ts
@@ -0,0 +1,124 @@
+import { IObjectOf, Fn, Keys } from "@thi.ng/api";
+import { DGraph } from "@thi.ng/dgraph";
+
+interface IComponent {
+    start(): boolean;
+    stop(): boolean;
+}
+
+class Logger implements IComponent {
+    info(msg: string) {
+        console.log(`[info] ${msg}`);
+    }
+    start() {
+        this.info("start logger");
+        return true;
+    }
+    stop() {
+        this.info("stop logger");
+        return true;
+    }
+}
+
+class DB implements IComponent {
+    constructor(protected logger: Logger, protected state: State) {}
+
+    start() {
+        this.logger.info("start db");
+        return true;
+    }
+    stop() {
+        this.logger.info("stop db");
+        return true;
+    }
+}
+
+class State implements IComponent {
+    constructor(protected logger: Logger) {}
+
+    start() {
+        this.logger.info("start state");
+        return true;
+    }
+    stop() {
+        this.logger.info("stop state");
+        return true;
+    }
+}
+
+type SystemMap<T> = Record<Keys<T>, IComponent>;
+
+type ComponentFactory<T extends SystemMap<T>> = Fn<T, IComponent>;
+
+type SystemSpecs<T extends SystemMap<T>> = IObjectOf<{
+    factory: ComponentFactory<T>;
+    deps?: Keys<T>[];
+}>;
+
+class System<T extends SystemMap<T>> {
+    components: T;
+    topo: Keys<T>[];
+
+    constructor(map: SystemSpecs<T>) {
+        const graph = new DGraph<Keys<T>>();
+        for (let id in map) {
+            const deps = map[id].deps;
+            if (deps) {
+                for (let d of deps) {
+                    graph.addDependency(<Keys<T>>id, d);
+                }
+            } else {
+                graph.addNode(<Keys<T>>id);
+            }
+        }
+        this.topo = graph.sort();
+        this.components = <any>{};
+        for (let id of this.topo) {
+            (<any>this.components)[id] = map[<any>id].factory(this.components);
+        }
+    }
+
+    start() {
+        for (let id of this.topo) {
+            if (!this.components[id].start()) {
+                console.warn(`error starting component: ${id}`);
+            }
+        }
+    }
+    stop() {
+        for (let id of this.topo.slice().reverse()) {
+            if (!this.components[id].stop()) {
+                console.warn(`error stopping component: ${id}`);
+            }
+        }
+    }
+}
+
+interface FooSys {
+    db: DB;
+    logger: Logger;
+    state: State;
+    dummy: IComponent;
+}
+
+const foo = new System<FooSys>({
+    db: {
+        factory: (deps) => new DB(<Logger>deps.logger, <State>deps.state),
+        deps: ["logger", "state"],
+    },
+    logger: { factory: () => new Logger() },
+    state: {
+        factory: (deps) => new State(<Logger>deps.logger),
+        deps: ["logger"],
+    },
+    dummy: {
+        factory: ({ logger }) => ({
+            start: () => ((<Logger>logger).info("dummy start"), true),
+            stop: () => ((<Logger>logger).info("dummy stop"), true),
+        }),
+    },
+});
+
+foo.start();
+
+foo.stop();
diff --git a/packages/system/.npmignore b/packages/system/.npmignore
new file mode 100644
index 0000000000..c6f44618c9
--- /dev/null
+++ b/packages/system/.npmignore
@@ -0,0 +1,22 @@
+.ae
+.cache
+.meta
+.nyc_output
+*.gz
+*.html
+*.svg
+*.tgz
+*.h
+*.o
+*.wasm
+*.tpl.md
+bench
+build
+coverage
+dev
+doc
+export
+src*
+test
+tools
+tsconfig.json
diff --git a/packages/system/LICENSE b/packages/system/LICENSE
new file mode 100644
index 0000000000..8dada3edaf
--- /dev/null
+++ b/packages/system/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+      "Work" shall mean the work of authorship, whether in Source or
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+      "Contribution" shall mean any work of authorship, including
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+      "Contributor" shall mean Licensor and any individual or Legal Entity
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+   2. Grant of Copyright License. Subject to the terms and conditions of
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+      You may add Your own copyright statement to Your modifications and
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+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
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+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+   7. Disclaimer of Warranty. Unless required by applicable law or
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+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
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+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
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+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/packages/system/README.md b/packages/system/README.md
new file mode 100644
index 0000000000..ba58209604
--- /dev/null
+++ b/packages/system/README.md
@@ -0,0 +1,167 @@
+<!-- This file is generated - DO NOT EDIT! -->
+
+# ![@thi.ng/system](https://media.thi.ng/umbrella/banners/thing-system.svg?1585848215)
+
+[![npm version](https://img.shields.io/npm/v/@thi.ng/system.svg)](https://www.npmjs.com/package/@thi.ng/system)
+![npm downloads](https://img.shields.io/npm/dm/@thi.ng/system.svg)
+[![Twitter Follow](https://img.shields.io/twitter/follow/thing_umbrella.svg?style=flat-square&label=twitter)](https://twitter.com/thing_umbrella)
+
+This project is part of the
+[@thi.ng/umbrella](https://github.com/thi-ng/umbrella/) monorepo.
+
+- [About](#about)
+  - [Status](#status)
+- [Installation](#installation)
+- [Dependencies](#dependencies)
+- [API](#api)
+- [Authors](#authors)
+- [License](#license)
+
+## About
+
+Minimal DI / life cycle container for stateful app components.
+
+Inspired by Stuart Sierra's
+[component](https://github.com/stuartsierra/component) framework for
+Clojure/ClojureScript.
+
+### Status
+
+**ALPHA** - bleeding edge / work-in-progress
+
+## Installation
+
+```bash
+yarn add @thi.ng/system
+```
+
+Package sizes (gzipped): ESM: 377 bytes / CJS: 436 bytes / UMD: 532 bytes
+
+## Dependencies
+
+- [@thi.ng/api](https://github.com/thi-ng/umbrella/tree/develop/packages/api)
+- [@thi.ng/dgraph](https://github.com/thi-ng/umbrella/tree/develop/packages/dgraph)
+- [tslib](https://github.com/thi-ng/umbrella/tree/develop/packages/undefined)
+
+## API
+
+[Generated API docs](https://docs.thi.ng/umbrella/system/)
+
+TODO
+
+```ts
+import { defSystem, ILifecycle } from "@thi.ng/system";
+
+// Step 1: Define the structure / components of your system
+
+interface FooSys {
+    db: DB;
+    cache: Cache;
+    logger: Logger;
+    dummy: ILifecycle;
+}
+
+// Step 2: Provide component implementations
+// Components can be classes or any object implementing the
+// `ILifecycle` interface...
+
+class Logger implements ILifecycle {
+    info(msg: string) {
+        console.log(msg);
+    }
+    async start() {
+        this.info("start logger");
+        return true;
+    }
+    async stop() {
+        this.info("stop logger");
+        return true;
+    }
+}
+
+// DB requires a logger & cache
+
+class DB implements ILifecycle {
+    constructor(protected logger: Logger, protected cache: Cache) {}
+
+    async start() {
+        this.logger.info("start db");
+        return true;
+    }
+    async stop() {
+        this.logger.info("stop db");
+        return true;
+    }
+}
+
+class Cache implements ILifecycle {
+    constructor(protected logger: Logger) {}
+
+    async start() {
+        this.logger.info("start cache");
+        return true;
+    }
+    async stop() {
+        this.logger.info("stop cache");
+        return true;
+    }
+}
+
+// Step 3: Define system & component dependencies
+// This will initialize all components in dependency order
+
+// - All arg types and dependency IDs are inferred / type checked
+// - `System` itself implements `ILifecycle`, so can be used to form
+//   nested systems
+
+const FOO = defSystem<FooSys>({
+    db: {
+        factory: (deps) => new DB(deps.logger, deps.state),
+        deps: ["logger", "state"],
+    },
+    logger: { factory: () => new Logger() },
+    cache: {
+        factory: ({ logger }) => new Cache(logger),
+        deps: ["logger"],
+    },
+
+    dummy: {
+        factory: ({ logger }) => ({
+            async start() {
+                logger.info("start dummy");
+                return true;
+            },
+            async stop() {
+                logger.info("stop dummy");
+                return true;
+            },
+        }),
+        deps: ["logger"]
+    }
+});
+
+// Step 4: Asynchronously start all components in dependency order
+FOO.start();
+// start logger
+// start cache
+// start dummy
+// start db
+
+// Step 5 (optional): Async shutdown all (in reverse order)
+FOO.stop();
+// stop db
+// stop dummy
+// stop cache
+// stop logger
+
+// Calls stop() & if successful followed by start()
+FOO.reset();
+```
+
+## Authors
+
+Karsten Schmidt
+
+## License
+
+&copy; 2020 Karsten Schmidt // Apache Software License 2.0
diff --git a/packages/system/README.tpl.md b/packages/system/README.tpl.md
new file mode 100644
index 0000000000..ad30868be1
--- /dev/null
+++ b/packages/system/README.tpl.md
@@ -0,0 +1,163 @@
+# ${pkg.banner}
+
+[![npm version](https://img.shields.io/npm/v/${pkg.name}.svg)](https://www.npmjs.com/package/${pkg.name})
+![npm downloads](https://img.shields.io/npm/dm/${pkg.name}.svg)
+[![Twitter Follow](https://img.shields.io/twitter/follow/thing_umbrella.svg?style=flat-square&label=twitter)](https://twitter.com/thing_umbrella)
+
+This project is part of the
+[@thi.ng/umbrella](https://github.com/thi-ng/umbrella/) monorepo.
+
+<!-- TOC -->
+
+## About
+
+${pkg.description}
+
+Inspired by Stuart Sierra's
+[component](https://github.com/stuartsierra/component) framework for
+Clojure/ClojureScript.
+
+${status}
+
+${supportPackages}
+
+${relatedPackages}
+
+${blogPosts}
+
+## Installation
+
+```bash
+yarn add ${pkg.name}
+```
+
+${pkg.size}
+
+## Dependencies
+
+${pkg.deps}
+
+${examples}
+
+## API
+
+${docLink}
+
+TODO
+
+```ts
+import { defSystem, ILifecycle } from "@thi.ng/system";
+
+// Step 1: Define the structure / components of your system
+
+interface FooSys {
+    db: DB;
+    cache: Cache;
+    logger: Logger;
+    dummy: ILifecycle;
+}
+
+// Step 2: Provide component implementations
+// Components can be classes or any object implementing the
+// `ILifecycle` interface...
+
+class Logger implements ILifecycle {
+    info(msg: string) {
+        console.log(`[info] ${msg}`);
+    }
+    async start() {
+        this.info("start logger");
+        return true;
+    }
+    async stop() {
+        this.info("stop logger");
+        return true;
+    }
+}
+
+// DB requires a logger & cache
+
+class DB implements ILifecycle {
+    constructor(protected logger: Logger, protected cache: Cache) {}
+
+    async start() {
+        this.logger.info("start db");
+        return true;
+    }
+    async stop() {
+        this.logger.info("stop db");
+        return true;
+    }
+}
+
+class Cache implements ILifecycle {
+    constructor(protected logger: Logger) {}
+
+    async start() {
+        this.logger.info("start cache");
+        return true;
+    }
+    async stop() {
+        this.logger.info("stop cache");
+        return true;
+    }
+}
+
+// Step 3: Define system & component dependencies
+// This will initialize all components in dependency order
+
+// - All arg types and dependency IDs are inferred / type checked
+// - `System` itself implements `ILifecycle`, so can be used to form
+//   nested systems
+
+const FOO = defSystem<FooSys>({
+    db: {
+        factory: (deps) => new DB(deps.logger, deps.state),
+        deps: ["logger", "state"],
+    },
+    logger: { factory: () => new Logger() },
+    cache: {
+        factory: ({ logger }) => new Cache(logger),
+        deps: ["logger"],
+    },
+
+    dummy: {
+        factory: ({ logger }) => ({
+            async start() {
+                logger.info("start dummy");
+                return true;
+            },
+            async stop() {
+                logger.info("stop dummy");
+                return true;
+            },
+        }),
+        deps: ["logger"]
+    }
+});
+
+// Step 4: Asynchronously start all components in dependency order
+FOO.start();
+// [info] start logger
+// [info] start cache
+// [info] start dummy
+// [info] start db
+
+// Step 5 (optional): Async shutdown all (in reverse order)
+FOO.stop();
+// [info] stop db
+// [info] stop dummy
+// [info] stop cache
+// [info] stop logger
+
+// Calls stop() & if successful followed by start()
+FOO.reset();
+```
+
+## Authors
+
+${authors}
+
+## License
+
+&copy; ${copyright} // ${license}
diff --git a/packages/system/api-extractor.json b/packages/system/api-extractor.json
new file mode 100644
index 0000000000..94972e6bed
--- /dev/null
+++ b/packages/system/api-extractor.json
@@ -0,0 +1,3 @@
+{
+    "extends": "../../api-extractor.json"
+}
diff --git a/packages/system/package.json b/packages/system/package.json
new file mode 100644
index 0000000000..3842ba901f
--- /dev/null
+++ b/packages/system/package.json
@@ -0,0 +1,61 @@
+{
+    "name": "@thi.ng/system",
+    "version": "0.0.1",
+    "description": "Minimal DI / life cycle container for stateful app components",
+    "module": "./index.js",
+    "main": "./lib/index.js",
+    "umd:main": "./lib/index.umd.js",
+    "typings": "./index.d.ts",
+    "repository": {
+        "type": "git",
+        "url": "https://github.com/thi-ng/umbrella.git"
+    },
+    "homepage": "https://github.com/thi-ng/umbrella/tree/master/packages/system",
+    "author": "Karsten Schmidt <k+npm@thi.ng>",
+    "license": "Apache-2.0",
+    "scripts": {
+        "build": "yarn clean && yarn build:es6 && node ../../scripts/bundle-module",
+        "build:release": "yarn clean && yarn build:es6 && node ../../scripts/bundle-module all",
+        "build:es6": "tsc --declaration",
+        "build:test": "rimraf build && tsc -p test/tsconfig.json",
+        "test": "mocha test",
+        "cover": "nyc mocha test && nyc report --reporter=lcov",
+        "clean": "rimraf *.js *.d.ts *.map .nyc_output build coverage doc lib",
+        "doc:readme": "ts-node -P ../../tools/tsconfig.json ../../tools/src/readme.ts",
+        "doc:ae": "mkdir -p .ae/doc .ae/temp && node_modules/.bin/api-extractor run --local --verbose",
+        "doc": "node_modules/.bin/typedoc --mode modules --out doc src",
+        "pub": "yarn build:release && yarn publish --access public"
+    },
+    "devDependencies": {
+        "@istanbuljs/nyc-config-typescript": "^1.0.1",
+        "@microsoft/api-extractor": "^7.7.8",
+        "@types/mocha": "^7.0.1",
+        "@types/node": "^13.7.4",
+        "mocha": "^7.0.1",
+        "nyc": "^15.0.0",
+        "ts-node": "^8.6.2",
+        "typedoc": "^0.16.10",
+        "typescript": "^3.8.3"
+    },
+    "dependencies": {
+        "@thi.ng/api": "^6.9.0",
+        "@thi.ng/dgraph": "^1.1.25",
+        "tslib": "^1.11.1"
+    },
+    "keywords": [
+        "component",
+        "DI",
+        "dependency graph",
+        "dependency injection",
+        "ES6",
+        "typescript"
+    ],
+    "publishConfig": {
+        "access": "public"
+    },
+    "sideEffects": false,
+    "thi.ng": {
+        "status": "alpha",
+        "year": 2020
+    }
+}
diff --git a/packages/system/src/api.ts b/packages/system/src/api.ts
new file mode 100644
index 0000000000..6b557c3c34
--- /dev/null
+++ b/packages/system/src/api.ts
@@ -0,0 +1,18 @@
+import type { Keys, Fn } from "@thi.ng/api";
+
+export interface ILifecycle {
+    start(): Promise<boolean>;
+    stop(): Promise<boolean>;
+}
+
+export type SystemMap<T> = Record<Keys<T>, ILifecycle>;
+
+export type ComponentFactory<T extends SystemMap<T>> = Fn<T, ILifecycle>;
+
+export type SystemSpecs<T extends SystemMap<T>> = Record<
+    Keys<T>,
+    {
+        factory: ComponentFactory<T>;
+        deps?: Keys<T>[];
+    }
+>;
diff --git a/packages/system/src/index.ts b/packages/system/src/index.ts
new file mode 100644
index 0000000000..2433d3a6d8
--- /dev/null
+++ b/packages/system/src/index.ts
@@ -0,0 +1,2 @@
+export * from "./api";
+export * from "./system";
diff --git a/packages/system/src/system.ts b/packages/system/src/system.ts
new file mode 100644
index 0000000000..42352835e4
--- /dev/null
+++ b/packages/system/src/system.ts
@@ -0,0 +1,52 @@
+import type { Keys } from "@thi.ng/api";
+import { DGraph } from "@thi.ng/dgraph";
+import type { ILifecycle, SystemMap, SystemSpecs } from "./api";
+
+export const defSystem = <T extends SystemMap<T>>(map: SystemSpecs<T>) =>
+    new System<T>(map);
+
+export class System<T extends SystemMap<T>> implements ILifecycle {
+    components: T;
+    topology: Keys<T>[];
+
+    constructor(map: SystemSpecs<T>) {
+        const graph = new DGraph<Keys<T>>();
+        for (let id in map) {
+            const deps = map[id].deps;
+            if (deps) {
+                for (let d of deps) {
+                    graph.addDependency(<Keys<T>>id, d);
+                }
+            } else {
+                graph.addNode(<Keys<T>>id);
+            }
+        }
+        this.topology = graph.sort();
+        this.components = <any>{};
+        for (let id of this.topology) {
+            this.components[id] = <any>map[id].factory(this.components);
+        }
+    }
+
+    async start() {
+        for (let id of this.topology) {
+            if (!(await this.components[id].start())) {
+                console.warn(`error starting component: ${id}`);
+            }
+        }
+        return true;
+    }
+
+    async stop() {
+        for (let id of this.topology.slice().reverse()) {
+            if (!(await this.components[id].stop())) {
+                console.warn(`error stopping component: ${id}`);
+            }
+        }
+        return true;
+    }
+
+    async reset() {
+        return (await this.stop()) && (await this.start());
+    }
+}
diff --git a/packages/system/test/index.ts b/packages/system/test/index.ts
new file mode 100644
index 0000000000..8a12dffc9f
--- /dev/null
+++ b/packages/system/test/index.ts
@@ -0,0 +1,94 @@
+import * as assert from "assert";
+import { defSystem, ILifecycle } from "../src";
+
+describe("system", () => {
+    it("basic", async () => {
+        const log: string[] = [];
+
+        class Logger implements ILifecycle {
+            info(msg: string) {
+                log.push(msg);
+            }
+            async start() {
+                this.info("start logger");
+                return true;
+            }
+            async stop() {
+                this.info("stop logger");
+                return true;
+            }
+        }
+
+        class DB implements ILifecycle {
+            constructor(protected logger: Logger, protected state: Cache) {}
+
+            async start() {
+                this.logger.info("start db");
+                return true;
+            }
+            async stop() {
+                this.logger.info("stop db");
+                return true;
+            }
+        }
+
+        class Cache implements ILifecycle {
+            constructor(protected logger: Logger) {}
+
+            async start() {
+                this.logger.info("start cache");
+                return true;
+            }
+            async stop() {
+                this.logger.info("stop cache");
+                return true;
+            }
+        }
+
+        interface FooSys {
+            db: DB;
+            logger: Logger;
+            state: Cache;
+            dummy: ILifecycle;
+        }
+
+        const foo = defSystem<FooSys>({
+            db: {
+                factory: (deps) => new DB(deps.logger, deps.state),
+                deps: ["logger", "state"],
+            },
+            logger: { factory: () => new Logger() },
+            state: {
+                factory: ({ logger }) => new Cache(logger),
+                deps: ["logger"],
+            },
+            dummy: {
+                factory: ({ logger }) => ({
+                    async start() {
+                        logger.info("start dummy");
+                        return true;
+                    },
+                    async stop() {
+                        logger.info("stop dummy");
+                        return true;
+                    },
+                }),
+                deps: ["logger"],
+            },
+        });
+
+        await foo.start();
+        await foo.stop();
+
+        assert.deepEqual(log, [
+            "start logger",
+            "start cache",
+            "start dummy",
+            "start db",
+            "stop db",
+            "stop dummy",
+            "stop cache",
+            "stop logger",
+        ]);
+    });
+});
diff --git a/packages/system/test/tsconfig.json b/packages/system/test/tsconfig.json
new file mode 100644
index 0000000000..f6e63560dd
--- /dev/null
+++ b/packages/system/test/tsconfig.json
@@ -0,0 +1,11 @@
+{
+    "extends": "../../../tsconfig.json",
+    "compilerOptions": {
+        "outDir": "../build",
+        "module": "commonjs"
+    },
+    "include": [
+        "./**/*.ts",
+        "../src/**/*.ts"
+    ]
+}
diff --git a/packages/system/tsconfig.json b/packages/system/tsconfig.json
new file mode 100644
index 0000000000..893b9979c5
--- /dev/null
+++ b/packages/system/tsconfig.json
@@ -0,0 +1,11 @@
+{
+    "extends": "../../tsconfig.json",
+    "compilerOptions": {
+        "outDir": ".",
+        "module": "es6",
+        "target": "es6"
+    },
+    "include": [
+        "./src/**/*.ts"
+    ]
+}