diff --git a/README.md b/README.md
index d95d644..6122698 100644
--- a/README.md
+++ b/README.md
@@ -147,6 +147,33 @@ fastify.listen(3000, err => {
 
 As you can see there is no need to close the client, since is done internally. Promises and async await are supported as well.
 
+### Name option
+If you need to have multiple databases set up, then you can name each one of them by passing `name: 'foo'`. It will then be accessible as `fastify.pg.foo` instead of `fastify.pg`.
+You can't use both named and an unnamed postgres conenction at once.
+
+```js
+const fastify = require('fastify')()
+
+fastify.register(require('fastify-postgres'), {
+  connectionString: 'postgres://postgres@localhost/postgres',
+  name: 'foo'
+})
+
+fastify.get('/user/:id', (req, reply) => {
+  fastify.pg.foo.query(
+    'SELECT id, username, hash, salt FROM users WHERE id=$1', [req.params.id],
+    function onResult (err, result) {
+      reply.send(err || result)
+    }
+  )
+})
+
+fastify.listen(3000, err => {
+  if (err) throw err
+  console.log(`server listening on ${fastify.server.address().port}`)
+})
+```
+
 ### Native option
 If you want to gain the maximum performances you can install [pg-native](https://github.com/brianc/node-pg-native), and pass `native: true` to the plugin options.
 *Note: it requires PostgreSQL client libraries & tools installed, see [instructions](https://github.com/brianc/node-pg-native#install).*
@@ -211,10 +238,24 @@ Install the compiler and typings for pg module:
 npm install --save-dev typescript @types/pg
 ```
 
-You can find examples in the [examples/typescript](./examples/typescript) directory.
+Add the `pg` property to `FastifyInstance`. Like this if you use an unnamed instance:
+
+```typescript
+import type { PostgresDb } from 'fastify-postgres';
+
+declare module 'fastify' {
+  export interface FastifyInstance {
+    pg: PostgresDb;
+  }
+}
+```
+
+More examples in the [examples/typescript](./examples/typescript) directory.
 
 ## Development and Testing
 
+### Docker approach
+
 First, start postgres with:
 
 ```
@@ -234,6 +275,18 @@ CREATE TABLE
 $ npm test
 ```
 
+### Custom Postgres approach
+
+1. Set up a database of your choice oin a postgres server of your choice
+2. Create the required table using
+    ```sql
+    CREATE TABLE users(id serial PRIMARY KEY, username VARCHAR (50) NOT NULL);
+    ```
+3. Specify a connection string to it in a `DATABASE_TEST_URL` environment variable when you run the tests
+    ```bash
+    DATABASE_TEST_URL="postgres://username:password@localhost/something_thats_a_test_database" npm test
+    ```
+
 ## Acknowledgements
 
 This project is kindly sponsored by:
diff --git a/index.js b/index.js
index a6dda6e..731b444 100644
--- a/index.js
+++ b/index.js
@@ -85,9 +85,9 @@ function fastifyPostgres (fastify, options, next) {
   if (name) {
     if (!fastify.pg) {
       fastify.decorate('pg', {})
-    }
-
-    if (fastify.pg[name]) {
+    } else if (fastify.pg.pool instanceof pg.Pool) {
+      return next(new Error('fastify-postgres already has an unnamed instance registered'))
+    } else if (fastify.pg[name]) {
       return next(new Error(`fastify-postgres '${name}' instance name has already been registered`))
     }
 
diff --git a/test/helpers.js b/test/helpers.js
new file mode 100644
index 0000000..c068533
--- /dev/null
+++ b/test/helpers.js
@@ -0,0 +1,11 @@
+'use strict'
+
+const BAD_DB_NAME = 'db_that_does_not_exist'
+const connectionString = process.env.DATABASE_TEST_URL || 'postgres://postgres:postgres@localhost/postgres'
+const connectionStringBadDbName = connectionString.replace(/\/[^/]+$/, '/' + BAD_DB_NAME)
+
+module.exports = Object.freeze({
+  BAD_DB_NAME,
+  connectionString,
+  connectionStringBadDbName
+})
diff --git a/test/initialization.test.js b/test/initialization.test.js
index 083ed9d..a7d6546 100644
--- a/test/initialization.test.js
+++ b/test/initialization.test.js
@@ -4,6 +4,7 @@ const t = require('tap')
 const test = t.test
 const Fastify = require('fastify')
 const fastifyPostgres = require('../index')
+const { connectionString } = require('./helpers')
 
 test('Should be able to use native module', (t) => {
   t.plan(2)
@@ -12,7 +13,7 @@ test('Should be able to use native module', (t) => {
   t.teardown(() => fastify.close())
 
   fastify.register(fastifyPostgres, {
-    connectionString: 'postgres://postgres:postgres@localhost/postgres',
+    connectionString,
     native: true
   })
 
@@ -38,7 +39,7 @@ test('Should be able to use an alternative pg module', (t) => {
   t.teardown(() => fastify.close())
 
   fastify.register(fastifyPostgres, {
-    connectionString: 'postgres://postgres:postgres@localhost/postgres',
+    connectionString,
     pg: altPg
   })
 
@@ -64,7 +65,7 @@ test('Should not throw if registered within different scopes (with and without n
 
   fastify.register(function scopeOne (instance, opts, next) {
     instance.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString
     })
 
     next()
@@ -72,12 +73,12 @@ test('Should not throw if registered within different scopes (with and without n
 
   fastify.register(function scopeTwo (instance, opts, next) {
     instance.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'one'
     })
 
     instance.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'two'
     })
 
@@ -96,16 +97,37 @@ test('Should throw when trying to register multiple instances without giving a n
   t.teardown(() => fastify.close())
 
   fastify.register(fastifyPostgres, {
-    connectionString: 'postgres://postgres:postgres@localhost/postgres'
+    connectionString
   })
 
   fastify.register(fastifyPostgres, {
-    connectionString: 'postgres://postgres:postgres@localhost/postgres'
+    connectionString
   })
 
   fastify.ready((err) => {
     t.ok(err)
-    t.is(err.message, 'fastify-postgres has already been registered')
+    t.is((err || {}).message, 'fastify-postgres has already been registered')
+  })
+})
+
+test('Should throw when trying to register a named instance after an unnamed', (t) => {
+  t.plan(2)
+
+  const fastify = Fastify()
+  t.teardown(() => fastify.close())
+
+  fastify.register(fastifyPostgres, {
+    connectionString
+  })
+
+  fastify.register(fastifyPostgres, {
+    connectionString,
+    name: 'two'
+  })
+
+  fastify.ready((err) => {
+    t.ok(err)
+    t.is((err || {}).message, 'fastify-postgres already has an unnamed instance registered')
   })
 })
 
@@ -118,17 +140,17 @@ test('Should throw when trying to register duplicate connection names', (t) => {
 
   fastify
     .register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name
     })
   fastify.register(fastifyPostgres, {
-    connectionString: 'postgres://postgres:postgres@localhost/postgres',
+    connectionString,
     name
   })
 
   fastify.ready((err) => {
     t.ok(err)
-    t.is(err.message, `fastify-postgres '${name}' instance name has already been registered`)
+    t.is((err || {}).message, `fastify-postgres '${name}' instance name has already been registered`)
   })
 })
 
@@ -139,7 +161,7 @@ test('fastify.pg namespace should exist', (t) => {
   t.teardown(() => fastify.close())
 
   fastify.register(fastifyPostgres, {
-    connectionString: 'postgres://postgres:postgres@localhost/postgres'
+    connectionString
   })
 
   fastify.ready((err) => {
@@ -159,7 +181,7 @@ test('fastify.pg.test namespace should exist', (t) => {
   t.teardown(() => fastify.close())
 
   fastify.register(fastifyPostgres, {
-    connectionString: 'postgres://postgres:postgres@localhost/postgres',
+    connectionString,
     name: 'test'
   })
 
diff --git a/test/query.test.js b/test/query.test.js
index 2209cdb..46c5046 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -4,6 +4,11 @@ const t = require('tap')
 const test = t.test
 const Fastify = require('fastify')
 const fastifyPostgres = require('../index')
+const {
+  BAD_DB_NAME,
+  connectionString,
+  connectionStringBadDbName
+} = require('./helpers')
 
 test('When fastify.pg root namespace is used:', (t) => {
   t.test('Should be able to connect and perform a query with a callback', (t) => {
@@ -13,7 +18,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString
     })
 
     fastify.ready((err) => {
@@ -40,7 +45,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString
     })
 
     fastify.ready((err) => {
@@ -60,7 +65,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString
     })
 
     fastify.ready((err) => {
@@ -85,10 +90,8 @@ test('When fastify.pg root namespace is used:', (t) => {
       const fastify = Fastify()
       t.teardown(() => fastify.close())
 
-      const DB_NAME = 'database_that_do_not_exist'
-
       fastify.register(fastifyPostgres, {
-        connectionString: `postgres://postgres:postgres@localhost/${DB_NAME}`
+        connectionString: connectionStringBadDbName
       })
 
       fastify.ready((err) => {
@@ -97,7 +100,7 @@ test('When fastify.pg root namespace is used:', (t) => {
         fastify.pg.query('SELECT NOW()', (err, result) => {
           t.is(result, undefined)
           t.ok(err)
-          t.is(err.message, `database "${DB_NAME}" does not exist`)
+          t.is(err.message, `database "${BAD_DB_NAME}" does not exist`)
         })
       })
     }
@@ -109,10 +112,8 @@ test('When fastify.pg root namespace is used:', (t) => {
     const fastify = Fastify()
     t.teardown(() => fastify.close())
 
-    const DB_NAME = 'database_that_do_not_exist'
-
     fastify.register(fastifyPostgres, {
-      connectionString: `postgres://postgres:postgres@localhost/${DB_NAME}`
+      connectionString: connectionStringBadDbName
     })
 
     fastify.ready((err) => {
@@ -125,7 +126,7 @@ test('When fastify.pg root namespace is used:', (t) => {
         })
         .catch((err) => {
           t.ok(err)
-          t.is(err.message, `database "${DB_NAME}" does not exist`)
+          t.is(err.message, `database "${BAD_DB_NAME}" does not exist`)
         })
     })
   })
@@ -141,7 +142,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -167,7 +168,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -187,7 +188,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -212,7 +213,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test',
       native: true
     })
@@ -237,10 +238,8 @@ test('When fastify.pg.test namespace is used:', (t) => {
     const fastify = Fastify()
     t.teardown(() => fastify.close())
 
-    const DB_NAME = 'database_that_do_not_exist'
-
     fastify.register(fastifyPostgres, {
-      connectionString: `postgres://postgres:postgres@localhost/${DB_NAME}`,
+      connectionString: connectionStringBadDbName,
       name: 'test'
     })
 
@@ -254,7 +253,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
         })
         .catch((err) => {
           t.ok(err)
-          t.is(err.message, `database "${DB_NAME}" does not exist`)
+          t.is(err.message, `database "${BAD_DB_NAME}" does not exist`)
         })
     })
   })
diff --git a/test/transaction.test.js b/test/transaction.test.js
index b136074..3fdcf9e 100644
--- a/test/transaction.test.js
+++ b/test/transaction.test.js
@@ -4,6 +4,11 @@ const t = require('tap')
 const test = t.test
 const Fastify = require('fastify')
 const fastifyPostgres = require('../index')
+const {
+  BAD_DB_NAME,
+  connectionString,
+  connectionStringBadDbName
+} = require('./helpers')
 
 test('When fastify.pg root namespace is used:', (t) => {
   t.test('Should be able to use transact util with a callback', (t) => {
@@ -13,7 +18,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString: process.env.DATABASE_TEST_URL || 'postgres://postgres:postgres@localhost/postgres'
     })
 
     fastify.ready((err) => {
@@ -50,7 +55,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString: process.env.DATABASE_TEST_URL || 'postgres://postgres:postgres@localhost/postgres'
     })
 
     fastify.ready((err) => {
@@ -87,7 +92,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString: process.env.DATABASE_TEST_URL || 'postgres://postgres:postgres@localhost/postgres'
     })
 
     fastify.ready((err) => {
@@ -128,7 +133,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString: process.env.DATABASE_TEST_URL || 'postgres://postgres:postgres@localhost/postgres'
     })
 
     fastify.ready((err) => {
@@ -182,7 +187,7 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres'
+      connectionString: process.env.DATABASE_TEST_URL || 'postgres://postgres:postgres@localhost/postgres'
     })
 
     fastify.ready((err) => {
@@ -231,10 +236,9 @@ test('When fastify.pg root namespace is used:', (t) => {
     t.plan(3)
 
     const fastify = Fastify()
-    const BAD_DB_NAME = 'db_that_does_not_exist'
 
     fastify.register(fastifyPostgres, {
-      connectionString: `postgres://postgres:postgres@localhost/${BAD_DB_NAME}`
+      connectionString: connectionStringBadDbName
     })
 
     fastify.ready((err) => {
@@ -259,7 +263,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -297,7 +301,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -337,7 +341,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -380,7 +384,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -435,7 +439,7 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.teardown(() => fastify.close())
 
     fastify.register(fastifyPostgres, {
-      connectionString: 'postgres://postgres:postgres@localhost/postgres',
+      connectionString,
       name: 'test'
     })
 
@@ -485,10 +489,9 @@ test('When fastify.pg.test namespace is used:', (t) => {
     t.plan(3)
 
     const fastify = Fastify()
-    const BAD_DB_NAME = 'db_that_does_not_exist'
 
     fastify.register(fastifyPostgres, {
-      connectionString: `postgres://postgres:postgres@localhost/${BAD_DB_NAME}`,
+      connectionString: connectionStringBadDbName,
       name: 'test'
     })