Building edgespark apps

EdgeSpark App Development

Use this skill for EdgeSpark-specific implementation and workflow decisions.

This skill is not EdgeSpark documentation. For exact contracts, read source, generated types, CLI help, and docs/Mintlify MCP. Use this skill for workflow, guardrails, and bug-prevention.

The reliable public surface in this repo is:

• the edgespark CLI
• scaffolded project structure from edgespark init
• generated src/__generated__/edgespark.d.ts
• generated src/__generated__/server-types.d.ts
• the @edgespark/web browser SDK

Use @edgespark/web and authUI.mount() as the default browser auth path for this repo unless custom forms are explicitly requested.

Read Order

Read only what is needed for the task:

1. edgespark.toml
2. repo or project agent instruction file (AGENTS.md, CLAUDE.md, or GEMINI.md)
3. src/__generated__/edgespark.d.ts
4. src/__generated__/server-types.d.ts
5. src/defs/index.ts, src/defs/db_schema.ts, src/defs/db_relations.ts, src/defs/runtime.ts, src/defs/storage_schema.ts
6. node_modules/@edgespark/web/dist/index.d.ts when installed for exact browser SDK types
7. node_modules/@edgespark/web/README.md when installed for managed auth appearance variable meanings and defaults

Then load the specific reference you need:

• Day-to-day development workflows by surface: dev-workflow.md
• Scaffold layout and generated-file rules: project-structure.md
• Error-prone server-side usage patterns: server-patterns.md
• Small web usage patterns for @edgespark/web: web-patterns.md
• Auth config, OAuth providers, callback URLs, managed auth theming, and Google One Tap: auth-patterns.md

Hard Rules

• Run edgespark <command> --help before assuming flags or exact behavior.
• Run edgespark commands on behalf of the user. Only hand off steps that explicitly require a human browser action.
• Never run multiple edgespark commands in parallel.
• Treat scaffolded src/__generated__/edgespark.d.ts and src/__generated__/server-types.d.ts as placeholders until edgespark pull types populates them.
• Do not edit files under src/__generated__/.
• Use @edgespark/web for new browser code.
• Use es.api.fetch() for app API calls, not bare fetch() to same-origin app routes.
• Use authUI.mount() for managed auth UI unless custom forms are explicitly requested.
• For managed auth theming, use appearance.theme and appearance.variables from @edgespark/web; do not tell users to edit SDK CSS for routine light/dark or brand theming.
• For custom browser auth flows, use client.auth from @edgespark/web, not manual /api/_es/auth/* calls.
• Import auth from edgespark/http, not edgespark.
• Auth is a managed service at /api/_es/auth/. OAuth callback URLs use /api/_es/auth/callback/<provider>, not /api/auth/.
• Treat /api/_es/auth/*, storage provider details, and deployment internals as platform implementation details unless the user is explicitly debugging them.
• Do not import runtime SDK values from edgespark inside src/defs/**.
• Use db.batch() instead of db.transaction().
• Use migration workflow for schema changes. Do not use DDL through edgespark db sql.
• Store S3 URIs in the database and return presigned URLs to clients.
• For client-originated uploads, generate presigned PUT URLs instead of streaming files through the Worker.
• Update src/defs/runtime.ts before using vars.get() or secret.get().
• Use edgespark ... --help for exact command syntax instead of duplicating help text in this skill.
• If exact behavior is unclear, prefer source code, generated types, or docs MCP over guessing.

Default Workflow

For the operational workflow by area, read dev-workflow.md.

Existing project

1. Read generated type files first.
2. Read the relevant defs files before changing schema, storage, or runtime keys.
3. Read the web SDK types before touching auth or browser API code.

Fresh scaffold

1. Inspect edgespark.toml to confirm server-only vs full-stack layout.
2. If generated files are placeholders, run edgespark pull types before making SDK assumptions.
3. Follow the scaffolded root, server/, and web/ agent instruction files for package boundaries.

When Stuck

1. Read the generated type files again before assuming an API shape.
2. Run the relevant edgespark ... --help command before guessing flags.
3. Use docs/Mintlify MCP for product documentation details.

Quick Start

Server:

import { db, storage, vars, secret, ctx } from "edgespark";
import { auth } from "edgespark/http";
import { posts, buckets } from "@defs";
import { Hono } from "hono";
import { eq } from "drizzle-orm";

const app = new Hono()
  .get("/api/posts", async (c) => {
    return c.json(await db.select().from(posts));
  })
  .post("/api/posts", async (c) => {
    const data = await c.req.json();
    const [post] = await db.insert(posts)
      .values({ ...data, user_id: auth.user!.id })
      .returning();
    return c.json(post, 201);
  });

export default app;

Web:

import { createEdgeSpark } from "@edgespark/web";
import "@edgespark/web/styles.css";

const es = createEdgeSpark();

es.authUI.mount(document.getElementById("auth")!, {
  redirectTo: "/dashboard",
});

const res = await es.api.fetch("/api/posts");
const posts = await res.json();