Secondlayer

Agent-native developer tools for Stacks. Dedicated indexing + real-time subgraphs + packaged protocol monitoring — all exposed through one API, one auth model, and three interchangeable front-ends (CLI, SDK, MCP).

Two ways to run it:

• Hosted — dedicated per-project Postgres + API + subgraph processor. Hobby is free (auto-pauses after 7d idle); paid tiers start at $149/mo.
• Self-host — the whole stack is MIT-licensed. docker compose up gets you indexer + API + processor on your own hardware. See docker/oss/README.md.

What's shipped

• Subgraphs — defineSubgraph() declares event filters + column schema; the processor indexes the chain into a typed Postgres view you query over REST.
• Sentries — packaged monitoring for protocols (whale transfers, admin role changes, contract deployments, custom print events). AI-triaged alerts delivered to a Slack-compatible webhook.
• Workflows SDK — defineWorkflow() with three durable step primitives (step.run, step.sleep, step.invoke) for writing your own automation.

Quickstart (hosted)

bun add -g @secondlayer/cli

sl login                            # magic-link email
sl project create my-app
sl project use my-app
sl instance create --plan hobby     # free tier; upgrade anytime
sl subgraphs deploy ./my-subgraph.ts

Full command reference: packages/cli/README.md.

Packages

Package	Description
@secondlayer/cli	sl binary — auth, project/instance lifecycle, subgraph deploy, Clarity code-gen
@secondlayer/sdk	TypeScript SDK — typed subgraph queries, workflow triggers, webhooks
@secondlayer/mcp	MCP server — exposes subgraphs, workflows, scaffolding to AI agents
@secondlayer/stacks	viem-style Stacks client — public/wallet, BNS, triggers, AI-SDK tools
@secondlayer/subgraphs	defineSubgraph() — declarative schema + event handlers
@secondlayer/workflows	defineWorkflow() — durable onchain automation
@secondlayer/shared	Shared db, schemas, auth primitives
@secondlayer/api	REST API — platform + dedicated + OSS modes

Surfaces

CLI

sl login
sl project use my-app
sl subgraphs deploy ./my-subgraph.ts
sl subgraphs query my-subgraph transfers --sort _block_height --order desc

SDK

import { SecondLayer } from "@secondlayer/sdk"

const sl = new SecondLayer({
  baseUrl: "https://<slug>.secondlayer.tools",
  apiKey: process.env.SL_SERVICE_KEY,
})

const { data } = await sl.subgraphs.queryTable("transfers", "events", {
  filters: { sender: "SP1234..." },
  sort: "_block_height",
  order: "desc",
  limit: 25,
})

REST API

curl -H "Authorization: Bearer $SL_SERVICE_KEY" \
  "https://<slug>.secondlayer.tools/api/subgraphs/transfers/events?_sort=_block_height&_order=desc&_limit=25"

MCP (AI agents)

Point Claude Desktop, Cursor, or any MCP client at npx @secondlayer/mcp with SL_SERVICE_KEY set. See packages/mcp/README.md.

Self-hosting

git clone https://github.com/ryanwaits/secondlayer
cd secondlayer
cp docker/.env.example docker/.env   # fill in secrets
docker compose -f docker/docker-compose.yml up -d

See docker/oss/README.md for the OSS-mode quickstart and docker/docs/ for operations, backups, and dedicated hosting internals.

Development

bun install
bun run build
bun run typecheck
bun run test

Releases flow through Changesets — bun run version to bump, bun run release to publish.

License

MIT