diff --git a/postgraphile/README.md b/postgraphile/README.md
index 6915d945..279ebd0a 100644
--- a/postgraphile/README.md
+++ b/postgraphile/README.md
@@ -23,8 +23,7 @@ Build the docker image in this directory. Start the `GraphiQL` frontend by:
 * GraphiQL frontend is available at `:3000/graphiql`
   GraphQL endpoint is available at `:3000/graphql`
 
-By default, this build will expose only the "public" schema - to add other schemas, use either the env variables,
-or a config file `config.toml` and set the env var `CONFIG_PATH` to point to its location. Example `toml`:
+By default, this build will expose only the "public" schema and will disable mutations - to change mutation behaviour, you can use an optional config file `config.toml` and set the env var `POSTGRAPHILE_CONFIG_PATH` to point to its location. Example `toml`:
 
 ```
 [database]
@@ -34,6 +33,7 @@ or a config file `config.toml` and set the env var `CONFIG_PATH` to point to its
     gq_schemas = ["public", "yourschema"]
     gq_user = "graphql"
     gq_password = "graphql"
+    disable_default_mutations = false
 ```
 
 ## Building
diff --git a/postgraphile/spec/server/config.spec.ts b/postgraphile/spec/server/config.spec.ts
index e66ff999..347ad8c3 100644
--- a/postgraphile/spec/server/config.spec.ts
+++ b/postgraphile/spec/server/config.spec.ts
@@ -25,7 +25,8 @@ describe('buildServerConfig', () => {
       host: 'example.com',
       database: 'example_database',
       schemas: ['public'],
-      ownerConnectionString: 'postgres://admin:admin@host'
+      ownerConnectionString: 'postgres://admin:admin@host',
+      disableDefaultMutations: true
     };
 
     postgraphileMiddleware = jasmine
diff --git a/postgraphile/src/config/parse.ts b/postgraphile/src/config/parse.ts
index a81cbab7..c51bff6b 100644
--- a/postgraphile/src/config/parse.ts
+++ b/postgraphile/src/config/parse.ts
@@ -24,6 +24,7 @@ export function parseConfig(
   let gqSchemas = ['public'];
   let gqUser = '';
   let gqPassword = '';
+  let disableDefaultMutations = true;
 
   if (configPath) {
     const tomlContents = readCallback(`${configPath}`).toString();
@@ -37,6 +38,9 @@ export function parseConfig(
     gqSchemas = parsedToml['database']['gq_schemas'];
     gqUser = parsedToml['database']['gq_user'] || gqUser;
     gqPassword = parsedToml['database']['gq_password'] || gqPassword;
+    disableDefaultMutations = parsedToml['database']['disable_default_mutations'] === undefined
+      ? true
+      : parsedToml['database']['disable_default_mutations'];
   }
 
   // Overwrite config values with env. vars if such are set
@@ -69,6 +73,7 @@ export function parseConfig(
         : `postgres://${user}:${password}@${host}:${port}`,
     database,
     schemas: gqSchemas,
-    ownerConnectionString: `postgres://${user}:${password}@${host}:${port}/${database}`
+    ownerConnectionString: `postgres://${user}:${password}@${host}:${port}/${database}`,
+    disableDefaultMutations
   };
 }
diff --git a/postgraphile/src/server/config.ts b/postgraphile/src/server/config.ts
index 03e07157..90be4f8a 100644
--- a/postgraphile/src/server/config.ts
+++ b/postgraphile/src/server/config.ts
@@ -5,7 +5,7 @@ import {
   PostgraphileOptions
 } from '../adapters/postgraphile';
 
-export const CONFIG_PATH_KEY = 'CONFIG_PATH';
+export const CONFIG_PATH_KEY = 'POSTGRAPHILE_CONFIG_PATH';
 export const SERVER_PORT_KEY = 'SERVER_PORT';
 
 const DEFAULT_SERVER_PORT = '3000';
@@ -27,7 +27,7 @@ export function buildServerConfig(
 
   const options: PostgraphileOptions = {
     appendPlugins: [PgSimplifyInflectorPlugin],
-    disableDefaultMutations: true,
+    disableDefaultMutations: databaseConfig.disableDefaultMutations,
     enableCors: true,
     exportGqlSchemaPath: 'schema.graphql',
     graphiql: true,
diff --git a/postgraphile/src/server/interface.ts b/postgraphile/src/server/interface.ts
index 9d6a066e..816ebcb1 100644
--- a/postgraphile/src/server/interface.ts
+++ b/postgraphile/src/server/interface.ts
@@ -18,6 +18,7 @@ export interface DatabaseConfig {
   database: string;
   schemas: string[];
   ownerConnectionString: string;
+  disableDefaultMutations: boolean;
 }
 
 export interface ServerConfig {