feat: router api

.gitignore

@@ -18,10 +18,8 @@ coverage
 cypress.env.json
 tests/cypress/screenshots
 
-# next.js
-.next/
-out/
-build
+# Vercel
+/apps/main/.vercel/
 
 # misc
 .DS_Store

apps/main/_api/router.ts

@@ -0,0 +1,22 @@
+import { type IncomingMessage, ServerResponse } from 'http'
+import { buildServer } from 'router-api/src/server'
+
+const server = buildServer()
+
+/**
+ * Vercel handler for API routes, using fastify under the hood. This is only used when deployed to Vercel.
+ * While in development, vite's dev server redirects /api/* calls to the router-api dev server.
+ */
+export default async function handler(request: IncomingMessage, response: ServerResponse) {
+  const start = Date.now()
+  await server.ready()
+  server.server.emit('request', request, response)
+  response.on('finish', () =>
+    server.log.info({
+      message: 'request finished',
+      method: request.method,
+      path: request.url,
+      runtimeMs: Date.now() - start,
+    }),
+  )
+}

apps/main/package.json

@@ -55,7 +55,7 @@
     "@types/node": "24.3.0",
     "@types/react": "*",
     "@types/react-dom": "*",
-    "@vitejs/plugin-react": "^5.0.1",
+    "@vitejs/plugin-react": "^5.0.4",
     "babel-plugin-styled-components": "^2.1.4",
     "eslint": "*",
     "eslint-config-custom": "*",

apps/main/tsconfig.json

@@ -11,5 +11,5 @@
       "@curvefi/prices-api/*": ["../../packages/prices-api/src/*"]
     }
   },
-  "include": ["src", "../../packages/ui/src/globals.d.ts"]
+  "include": ["src", "_api", "../../packages/ui/src/globals.d.ts"]
 }

apps/main/vite.config.ts

@@ -4,17 +4,15 @@ import react from '@vitejs/plugin-react'
 import svgr from 'vite-plugin-svgr'
 import vercel from 'vite-plugin-vercel'
 
+const { API_PROXY_TARGET = 'http://localhost:3010' } = process.env
+
 // https://vite.dev/config/
-export default defineConfig(({ command }) => ({
-  server: {
-    port: 3000,
-    hmr: true,
-  },
+export default defineConfig(({ command, mode }) => ({
+  // the local server starts on port 3000 by default, with hot module reload enabled and /api proxying
+  server: { port: 3000, hmr: true, proxy: { '/api': { target: API_PROXY_TARGET, changeOrigin: true } } },
   preview: { port: 3000 },
   plugins: [react(), svgr(), vercel()],
-  optimizeDeps: {
-    include: ['styled-components', '@mui/material', '@mui/icons-material'],
-  },
+  optimizeDeps: { include: ['styled-components', '@mui/material', '@mui/icons-material'] },
   resolve: {
     alias: [
       { find: '@', replacement: resolve(__dirname, './src') },
@@ -24,25 +22,14 @@ export default defineConfig(({ command }) => ({
       { find: '@curvefi/prices-api', replacement: resolve(__dirname, '../../packages/prices-api/src') },
     ],
   },
-  define: {
-    'process.env.NODE_ENV': command === 'serve' ? '"development"' : '"production"',
-  },
+  define: { 'process.env.NODE_ENV': command === 'serve' ? '"development"' : '"production"' },
   vercel: {
     buildCommand: 'yarn build',
     rewrites: [
-      {
-        source: '/favicon',
-        destination: '/favicon.ico',
-      },
-      {
-        source: '/security.txt',
-        destination: '/.well-known/security.txt',
-        statusCode: 308, // Permanent redirect
-      },
-      {
-        source: '/(.*)',
-        destination: '/index.html',
-      },
+      { source: '/favicon', destination: '/favicon.ico' },
+      { source: '/api/(.*)', destination: '/api/router' },
+      { source: '/security.txt', destination: '/.well-known/security.txt', statusCode: 308 /* Permanent redirect */ },
+      { source: '/(.*)', destination: '/index.html' },
     ],
   },
 }))

apps/router-api/.env

@@ -1,5 +1,7 @@
 # Router API service environment configuration
 # Copy to .env.local or export variables in your runtime environment.
+# Vitest E2E suites load this file automatically; ensure keys below point to
+# test-safe infrastructure before running `yarn workspace router-api test:e2e`.
 
 # Optional server overrides
 # PORT controls the listening port for the Fastify server.
@@ -8,3 +10,41 @@ PORT=3010
 HOST=0.0.0.0
 # SERVICE_NAME participates in /health responses for observability.
 SERVICE_NAME=router-api
+
+# RPC endpoints are configured dynamically based on Curve network identifiers.
+# Build the environment variable name as RPC_URL_${sanitizeId(id)} where sanitizeId uppercases and replaces non-alphanumeric characters with underscores.
+# Reference the supported network list in apps/router-api/src/networks.ts when provisioning keys.
+RPC_URL_ETHEREUM=https://ethereum.publicnode.com
+RPC_URL_OPTIMISM=https://optimism.drpc.org
+RPC_URL_XDC=https://rpc1.xinfin.network
+RPC_URL_BSC=https://bsc-dataseed1.binance.org/
+RPC_URL_BSC_TESTNET=https://data-seed-prebsc-1-s1.binance.org:8545/
+RPC_URL_XDAI=https://rpc.gnosischain.com
+RPC_URL_POLYGON=https://polygon-rpc.com
+RPC_URL_SONIC=https://rpc.soniclabs.com
+RPC_URL_X_LAYER=https://rpc.xlayer.tech
+RPC_URL_TAC=https://rpc.ankr.com/tac
+RPC_URL_FANTOM=https://rpc.ftm.tools/
+RPC_URL_FRAXTAL=https://rpc.frax.com
+RPC_URL_ZKSYNC=https://mainnet.era.zksync.io
+RPC_URL_HYPERLIQUID=https://rpc.hyperliquid.xyz/evm
+RPC_URL_MOONBEAM=https://moonbeam.public.blastapi.io
+RPC_URL_KAVA=https://evm.kava.io
+RPC_URL_TAC_TESTNET=https://turin.rpc.tac.build
+RPC_URL_MANTLE=https://rpc.mantle.xyz
+RPC_URL_MEGAETH=https://carrot.megaeth.com/rpc
+RPC_URL_BASE=https://base.drpc.org
+RPC_URL_PLASMA=https://rpc.plasma.to
+RPC_URL_MONAD=https://rpc.ankr.com/monad_testnet
+RPC_URL_EXPCHAIN=https://rpc0-testnet.expchain.ai
+RPC_URL_ARBITRUM=https://arb1.arbitrum.io/rpc
+RPC_URL_CELO=https://forno.celo.org
+RPC_URL_ETHERLINK=https://node.mainnet.etherlink.com/
+RPC_URL_AVALANCHE=https://api.avax.network/ext/bc/C/rpc
+RPC_URL_INK=https://rpc-gel.inkonchain.com
+RPC_URL_PLUME=https://rpc.plume.org
+RPC_URL_TAIKO=https://rpc.ankr.com/taiko
+RPC_URL_ARBITRUM_SEPOLIA=https://sepolia-rollup.arbitrum.io/rpc
+RPC_URL_CORN=https://rpc.ankr.com/corn_maizenet
+RPC_URL_NEON=https://devnet.neonevm.org
+RPC_URL_AURORA=https://mainnet.aurora.dev

apps/router-api/package.json

@@ -7,9 +7,7 @@
     "node": "22"
   },
   "scripts": {
-    "dev": "tsx watch src/local.ts",
-    "start": "node dist/local.js",
-    "build": "tsc --project tsconfig.build.json",
+    "dev": "tsx watch src/dev.ts",
     "lint": "eslint \"src/**/*.ts\"",
     "typecheck": "tsc --noEmit",
     "test": "vitest run",
@@ -21,9 +19,10 @@
   },
   "devDependencies": {
     "@types/node": "24.5.2",
+    "dotenv": "^17.2.3",
     "eslint": "*",
     "eslint-config-custom": "*",
-    "tsx": "^4.20.6",
+    "tsx": "4.20.6",
     "typescript": "*",
     "vitest": "^3.2.4"
   }

apps/router-api/src/curvejs.ts

@@ -0,0 +1,46 @@
+import { FastifyBaseLogger } from 'fastify/types/logger'
+import { type default as curveApi, createCurve } from '@curvefi/api'
+import { resolveRpc } from './rpc/network-metadata'
+
+export type CurveJS = typeof curveApi
+export type ChainId = number
+
+const instances: { [P in ChainId]?: Promise<CurveJS> } = {}
+
+const FACTORIES = [
+  'factory',
+  'cryptoFactory',
+  'twocryptoFactory',
+  'crvUSDFactory',
+  'tricryptoFactory',
+  'stableNgFactory',
+] as const
+
+async function hydrateCurve(curve: CurveJS, log: FastifyBaseLogger) {
+  const factories = FACTORIES.map((key) => curve[key])
+  await Promise.all(
+    factories.map(async (factory) => {
+      await factory.fetchPools()
+      if ('fetchNewPools' in factory) await factory.fetchNewPools()
+    }),
+  )
+  log.info({ message: 'curve client initialized', chainId: curve.chainId })
+  return () => Promise.all(factories.map((factory) => 'fetchNewPools' in factory && factory.fetchNewPools()))
+}
+
+/**
+ * Get a Curve.js instance for a specific chain ID, initializing it if necessary.
+ * The instance is cached for future use. Also returns a function to refresh the pool data.
+ */
+export const loadCurve = (chainId: number, log: FastifyBaseLogger) => {
+  if (!instances[chainId]) {
+    instances[chainId] = (async () => {
+      const curve = createCurve()
+      const { url } = await resolveRpc(chainId, curve)
+      await curve.init('JsonRpc', { url }, { chainId })
+      const refresh = await hydrateCurve(curve, log)
+      return curve
+    })()
+  }
+  return instances[chainId]!
+}

apps/router-api/src/local.ts → apps/router-api/src/dev.ts

@@ -1,6 +1,9 @@
+import dotenv from 'dotenv'
 import type { FastifyListenOptions } from 'fastify'
 import { buildServer } from './server'
 
+dotenv.config() // Load environment variables from .env file
+
 const loadConfigFromEnv = ({ HOST, PORT = 3010 } = process.env): FastifyListenOptions => ({
   port: Number(PORT),
   host: HOST,
@@ -9,6 +12,7 @@ const loadConfigFromEnv = ({ HOST, PORT = 3010 } = process.env): FastifyListenOp
 /**
  * Starts the Fastify server and sets up graceful shutdown handlers.
  * This function is invoked when running the application locally.
+ * On Vercel, we use the server instance directly in the API route handler of the main app.
  */
 async function start(): Promise<void> {
   const server = buildServer()

apps/router-api/src/routes/optimal-route.schemas.ts

@@ -0,0 +1,101 @@
+import { Address } from 'viem'
+import type { IRouteStep } from '@curvefi/api/lib/interfaces'
+
+export type Decimal = `${number}`
+
+export const ADDRESS_HEX_PATTERN = '^0x[a-fA-F0-9]{40}$'
+
+export const OptimalRoutePath = '/api/router/optimal-route'
+
+const AddressSchema = { type: 'string', pattern: ADDRESS_HEX_PATTERN } as const
+const AddressArraySchema = { type: 'array', items: AddressSchema, minItems: 1, maxItems: 1 } as const
+const AmountArraySchema = { type: 'array', items: { type: 'string' }, minItems: 1, maxItems: 1 } as const
+
+const optimalRouteQuerySchema = {
+  type: 'object',
+  required: ['tokenIn', 'tokenOut'],
+  additionalProperties: false,
+  properties: {
+    chainId: { type: 'integer', minimum: 1, default: 1 },
+    tokenIn: AddressArraySchema,
+    tokenOut: AddressArraySchema,
+    amountIn: AmountArraySchema,
+    amountOut: AmountArraySchema,
+  },
+} as const
+
+export type OptimalRouteQuery = {
+  chainId: number
+  tokenIn: [Address]
+  tokenOut: [Address]
+  amountIn?: [Decimal]
+  amountOut?: [Decimal]
+}
+
+const routeItemSchema = {
+  type: 'object',
+  required: ['amountOut', 'priceImpact', 'createdAt', 'route'],
+  properties: {
+    amountOut: { type: 'string' },
+    priceImpact: { anyOf: [{ type: 'number' }, { type: 'null' }] },
+    createdAt: { type: 'integer' },
+    route: {
+      type: 'array',
+      items: {
+        type: 'object',
+        required: ['tokenIn', 'tokenOut', 'protocol', 'action', 'args', 'chainId'],
+        properties: {
+          tokenIn: { type: 'array', items: { type: 'string' } },
+          tokenOut: { type: 'array', items: { type: 'string' } },
+          protocol: { type: 'string', enum: ['curve'] },
+          action: { type: 'string', enum: ['swap'] },
+          args: {
+            type: 'object',
+            required: ['poolId', 'swapAddress', 'swapParams', 'tvl'],
+            additionalProperties: true,
+            properties: {
+              poolId: { type: 'string' },
+              swapAddress: AddressSchema,
+              swapParams: {
+                description: 'Array of [inputCoinIndex, outputCoinIndex, swapType, amount, minAmountOut]',
+                type: 'array',
+                items: { type: 'integer' },
+                minItems: 5,
+                maxItems: 5,
+              },
+              poolAddress: AddressSchema,
+              basePool: AddressSchema,
+              baseToken: AddressSchema,
+              secondBasePool: AddressSchema,
+              secondBaseToken: AddressSchema,
+              tvl: { type: 'number' },
+            },
+            chainId: { type: 'integer' },
+          },
+        },
+      },
+    },
+  },
+} as const
+
+export const OptimalRouteSchema = {
+  querystring: optimalRouteQuerySchema,
+  response: { 200: { type: 'array', items: routeItemSchema } },
+}
+
+type RouteStep = {
+  tokenIn: [Address]
+  tokenOut: [Address]
+  protocol: 'curve'
+  action: 'swap'
+  args: Omit<IRouteStep, 'inputCoinAddress' | 'outputCoinAddress'>
+  chainId: number
+}
+
+export type RouteResponse = {
+  amountOut: string
+  priceImpact: number | null
+  createdAt: number
+  warnings: ('high-slippage' | 'low-exchange-rate')[]
+  route: RouteStep[]
+}