diff --git a/.env.example b/.env.example
index 07d25c6..07aa230 100644
--- a/.env.example
+++ b/.env.example
@@ -1,8 +1,24 @@
+# ── Required ────────────────────────────────────────────────────────────────────
+
+# PostgreSQL connection string (required)
 DATABASE_URL="postgresql://postgres:postgres@localhost:5432/guildpass"
+
+# Redis connection string (required)
 REDIS_URL="redis://localhost:6379"
+
+# ── Optional (safe defaults shown) ──────────────────────────────────────────────
+
+# Port the HTTP server listens on (default: 3000, range 1–65535)
 PORT=3000
+
+# Runtime environment: development | test | production (default: development)
 NODE_ENV=development
 
-# Contracts (fill after deployment)
-MEMBERSHIP_NFT_ADDRESS=""
+# ── Contracts (fill after deployment) ───────────────────────────────────────────
+
+# EVM chain ID the API operates on (default: 31337 for local Anvil/Hardhat)
 CHAIN_ID=31337
+
+# Deployed MembershipNFT contract address (0x-prefixed, 40 hex chars). Leave
+# empty to disable on-chain checks during local development.
+MEMBERSHIP_NFT_ADDRESS=""
diff --git a/README.md b/README.md
index a618b35..04b4e5e 100644
--- a/README.md
+++ b/README.md
@@ -141,6 +141,8 @@ This project uses ESLint to maintain code quality.
 
 See [`.env.example`](./.env.example) for all required variables.
 
+All environment variables are validated at startup by `apps/access-api/src/config.ts`. The server will refuse to start and print a clear error if any required variable is missing or malformed (invalid URL, port out of range, bad chain ID, or invalid contract address).
+
 ---
 
 ## Deferred Areas (Intentionally Not Implemented)
diff --git a/apps/access-api/jest.config.js b/apps/access-api/jest.config.js
new file mode 100644
index 0000000..17d8ced
--- /dev/null
+++ b/apps/access-api/jest.config.js
@@ -0,0 +1,6 @@
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+  roots: ['<rootDir>/src'],
+  testMatch: ['**/*.test.ts'],
+};
diff --git a/apps/access-api/src/config.test.ts b/apps/access-api/src/config.test.ts
new file mode 100644
index 0000000..86038b3
--- /dev/null
+++ b/apps/access-api/src/config.test.ts
@@ -0,0 +1,72 @@
+import { loadConfig } from '../config';
+
+const VALID: NodeJS.ProcessEnv = {
+  DATABASE_URL: 'postgresql://user:pass@localhost:5432/db',
+  REDIS_URL: 'redis://localhost:6379',
+  PORT: '3000',
+  NODE_ENV: 'test',
+  CHAIN_ID: '1',
+  MEMBERSHIP_NFT_ADDRESS: '',
+};
+
+describe('loadConfig', () => {
+  it('returns a valid config for a complete env', () => {
+    const cfg = loadConfig(VALID);
+    expect(cfg.databaseUrl).toBe(VALID.DATABASE_URL);
+    expect(cfg.redisUrl).toBe(VALID.REDIS_URL);
+    expect(cfg.port).toBe(3000);
+    expect(cfg.nodeEnv).toBe('test');
+    expect(cfg.chainId).toBe(1);
+    expect(cfg.membershipNftAddress).toBeNull();
+  });
+
+  it('applies defaults for PORT, NODE_ENV, and CHAIN_ID when omitted', () => {
+    const cfg = loadConfig({ DATABASE_URL: VALID.DATABASE_URL, REDIS_URL: VALID.REDIS_URL });
+    expect(cfg.port).toBe(3000);
+    expect(cfg.nodeEnv).toBe('development');
+    expect(cfg.chainId).toBe(31337);
+  });
+
+  it('parses a valid MEMBERSHIP_NFT_ADDRESS', () => {
+    const cfg = loadConfig({ ...VALID, MEMBERSHIP_NFT_ADDRESS: '0xabc123AB23456789abcdef01234567890ABCDEF01'.slice(0, 42) });
+    // any valid 42-char address
+    const addr = '0x' + 'a'.repeat(40);
+    const cfg2 = loadConfig({ ...VALID, MEMBERSHIP_NFT_ADDRESS: addr });
+    expect(cfg2.membershipNftAddress).toBe(addr);
+  });
+
+  it('throws when DATABASE_URL is missing', () => {
+    const env = { ...VALID };
+    delete env.DATABASE_URL;
+    expect(() => loadConfig(env)).toThrow('DATABASE_URL');
+  });
+
+  it('throws when REDIS_URL is missing', () => {
+    const env = { ...VALID };
+    delete env.REDIS_URL;
+    expect(() => loadConfig(env)).toThrow('REDIS_URL');
+  });
+
+  it('throws for an invalid DATABASE_URL', () => {
+    expect(() => loadConfig({ ...VALID, DATABASE_URL: 'not-a-url' })).toThrow('DATABASE_URL');
+  });
+
+  it('throws for an invalid REDIS_URL', () => {
+    expect(() => loadConfig({ ...VALID, REDIS_URL: 'not-a-url' })).toThrow('REDIS_URL');
+  });
+
+  it('throws for a PORT out of range', () => {
+    expect(() => loadConfig({ ...VALID, PORT: '99999' })).toThrow('PORT');
+    expect(() => loadConfig({ ...VALID, PORT: '0' })).toThrow('PORT');
+    expect(() => loadConfig({ ...VALID, PORT: 'abc' })).toThrow('PORT');
+  });
+
+  it('throws for an invalid CHAIN_ID', () => {
+    expect(() => loadConfig({ ...VALID, CHAIN_ID: '0' })).toThrow('CHAIN_ID');
+    expect(() => loadConfig({ ...VALID, CHAIN_ID: 'mainnet' })).toThrow('CHAIN_ID');
+  });
+
+  it('throws for a malformed MEMBERSHIP_NFT_ADDRESS', () => {
+    expect(() => loadConfig({ ...VALID, MEMBERSHIP_NFT_ADDRESS: '0xinvalid' })).toThrow('MEMBERSHIP_NFT_ADDRESS');
+  });
+});
diff --git a/apps/access-api/src/config.ts b/apps/access-api/src/config.ts
new file mode 100644
index 0000000..a547dab
--- /dev/null
+++ b/apps/access-api/src/config.ts
@@ -0,0 +1,65 @@
+const EVM_ADDRESS_RE = /^0x[0-9a-fA-F]{40}$/;
+
+function requireEnv(env: NodeJS.ProcessEnv, key: string): string {
+  const value = env[key];
+  if (!value) throw new Error(`Missing required environment variable: ${key}`);
+  return value;
+}
+
+function parseUrl(key: string, value: string): string {
+  try {
+    new URL(value);
+  } catch {
+    throw new Error(`Invalid URL for ${key}: "${value}"`);
+  }
+  return value;
+}
+
+function parsePort(key: string, raw: string): number {
+  const port = parseInt(raw, 10);
+  if (isNaN(port) || port < 1 || port > 65535) {
+    throw new Error(`Invalid port for ${key}: "${raw}"`);
+  }
+  return port;
+}
+
+function parseChainId(raw: string): number {
+  const id = parseInt(raw, 10);
+  if (isNaN(id) || id < 1) throw new Error(`Invalid CHAIN_ID: "${raw}"`);
+  return id;
+}
+
+function parseContractAddress(key: string, value: string): string {
+  if (!EVM_ADDRESS_RE.test(value)) {
+    throw new Error(`Invalid EVM address for ${key}: "${value}"`);
+  }
+  return value;
+}
+
+export interface Config {
+  databaseUrl: string;
+  redisUrl: string;
+  port: number;
+  nodeEnv: string;
+  membershipNftAddress: string | null;
+  chainId: number;
+}
+
+export function loadConfig(env: NodeJS.ProcessEnv = process.env): Config {
+  const databaseUrl = parseUrl('DATABASE_URL', requireEnv(env, 'DATABASE_URL'));
+  const redisUrl = parseUrl('REDIS_URL', requireEnv(env, 'REDIS_URL'));
+  const port = parsePort('PORT', env.PORT ?? '3000');
+  const nodeEnv = env.NODE_ENV ?? 'development';
+  const chainId = parseChainId(env.CHAIN_ID ?? '31337');
+
+  const rawAddress = env.MEMBERSHIP_NFT_ADDRESS;
+  const membershipNftAddress =
+    rawAddress && rawAddress !== ''
+      ? parseContractAddress('MEMBERSHIP_NFT_ADDRESS', rawAddress)
+      : null;
+
+  return { databaseUrl, redisUrl, port, nodeEnv, chainId, membershipNftAddress };
+}
+
+// Singleton — evaluated once at startup; throws if config is invalid.
+export const config: Config = loadConfig();
diff --git a/apps/access-api/src/index.ts b/apps/access-api/src/index.ts
index 4d52467..cdaf243 100644
--- a/apps/access-api/src/index.ts
+++ b/apps/access-api/src/index.ts
@@ -1,6 +1,7 @@
 import Fastify from 'fastify';
 import swagger from '@fastify/swagger';
 import swaggerUi from '@fastify/swagger-ui';
+import { config } from './config';
 import { registerRoutes } from './routes';
 
 const server = Fastify({ logger: true });
@@ -22,8 +23,7 @@ async function main() {
 
   registerRoutes(server);
 
-  const port = parseInt(process.env.PORT || '3000', 10);
-  await server.listen({ port, host: '0.0.0.0' });
+  await server.listen({ port: config.port, host: '0.0.0.0' });
 }
 
 main().catch((err) => {
diff --git a/apps/access-api/src/services/prisma.ts b/apps/access-api/src/services/prisma.ts
index 0d5d63d..2df0881 100644
--- a/apps/access-api/src/services/prisma.ts
+++ b/apps/access-api/src/services/prisma.ts
@@ -1,10 +1,11 @@
 import { PrismaClient } from '@prisma/client';
+import { config } from '../config';
 
 let prisma: PrismaClient | null = null;
 
 export function getPrisma(): PrismaClient {
   if (!prisma) {
-    prisma = new PrismaClient();
+    prisma = new PrismaClient({ datasources: { db: { url: config.databaseUrl } } });
   }
   return prisma;
 }