DynamoDB emulator for tests

Run DynamoDB locally for integration tests with fakecloud. 57 operations, transactions, PartiQL, streams, global tables. Any language, no Docker required, free.

Need a DynamoDB emulator for tests? Use fakecloud. Not a mock library — a real server that speaks the DynamoDB wire protocol.

curl -fsSL https://raw.githubusercontent.com/faiscadev/fakecloud/main/install.sh | bash
fakecloud

Point your AWS SDK at http://localhost:4566. That's the whole setup.

Why fakecloud for DynamoDB

57 DynamoDB operations at 100% conformance — tables, items, transactions (TransactWriteItems, TransactGetItems), PartiQL (ExecuteStatement, BatchExecuteStatement), backups, global tables, streams, secondary indexes.
Validated against AWS's own Smithy models on every commit (59,000+ generated test variants).
Any AWS SDK in any language. Real HTTP server on port 4566 — Python boto3, Node aws-sdk, Go aws-sdk-go-v2, Java, Kotlin, Rust, PHP all work identically.
No account, no auth token, no paid tier. AGPL-3.0.
No Docker required for DynamoDB (binary runs the storage engine in-process). Fastest local DynamoDB you can run.

Quick examples

Python (boto3)

import boto3
ddb = boto3.client('dynamodb',
    endpoint_url='http://localhost:4566',
    aws_access_key_id='test',
    aws_secret_access_key='test',
    region_name='us-east-1')

ddb.create_table(
    TableName='users',
    KeySchema=[{'AttributeName': 'id', 'KeyType': 'HASH'}],
    AttributeDefinitions=[{'AttributeName': 'id', 'AttributeType': 'S'}],
    BillingMode='PAY_PER_REQUEST')

ddb.put_item(TableName='users', Item={'id': {'S': 'u1'}, 'name': {'S': 'Alice'}})
resp = ddb.get_item(TableName='users', Key={'id': {'S': 'u1'}})
print(resp['Item'])

Node.js (AWS SDK v3)

process.env.AWS_ENDPOINT_URL = 'http://localhost:4566';
process.env.AWS_ACCESS_KEY_ID = 'test';
process.env.AWS_SECRET_ACCESS_KEY = 'test';
process.env.AWS_REGION = 'us-east-1';

import { DynamoDBClient, CreateTableCommand, PutItemCommand, GetItemCommand } from '@aws-sdk/client-dynamodb';
const ddb = new DynamoDBClient({});

await ddb.send(new CreateTableCommand({
  TableName: 'users',
  KeySchema: [{ AttributeName: 'id', KeyType: 'HASH' }],
  AttributeDefinitions: [{ AttributeName: 'id', AttributeType: 'S' }],
  BillingMode: 'PAY_PER_REQUEST',
}));

Go

cfg, _ := config.LoadDefaultConfig(ctx,
    config.WithRegion("us-east-1"),
    config.WithCredentialsProvider(credentials.NewStaticCredentialsProvider("test", "test", "")),
    config.WithEndpointResolverWithOptions(aws.EndpointResolverWithOptionsFunc(
        func(s, r string, o ...interface{}) (aws.Endpoint, error) {
            return aws.Endpoint{URL: "http://localhost:4566"}, nil
        },
    )),
)
ddb := dynamodb.NewFromConfig(cfg)

AWS CLI

aws --endpoint-url http://localhost:4566 dynamodb create-table \
  --table-name users \
  --key-schema AttributeName=id,KeyType=HASH \
  --attribute-definitions AttributeName=id,AttributeType=S \
  --billing-mode PAY_PER_REQUEST

Transactions

ddb.transact_write_items(TransactItems=[
    {'Put': {'TableName': 'orders', 'Item': {'id': {'S': 'o1'}, 'total': {'N': '100'}}}},
    {'Update': {'TableName': 'accounts', 'Key': {'id': {'S': 'a1'}},
                'UpdateExpression': 'ADD balance :delta',
                'ExpressionAttributeValues': {':delta': {'N': '-100'}}}},
])

Real transaction semantics: all-or-nothing, condition check failures roll back the whole batch.

Streams

ddb.create_table(
    TableName='events',
    KeySchema=[{'AttributeName': 'id', 'KeyType': 'HASH'}],
    AttributeDefinitions=[{'AttributeName': 'id', 'AttributeType': 'S'}],
    BillingMode='PAY_PER_REQUEST',
    StreamSpecification={'StreamEnabled': True, 'StreamViewType': 'NEW_AND_OLD_IMAGES'})

Stream records get published. Lambda event source mappings consume them.

How it differs from alternatives

Tool	Multi-language	Transactions	Streams	PartiQL	Real Lambda triggers
fakecloud	Any	Yes	Yes	Yes	Yes (real runtime code)
DynamoDB Local (AWS official)	Any (JVM required)	Yes	Yes	Yes	No (no cross-service)
Moto	Python only	Yes	Yes	Partial	Stubbed
aws-sdk-client-mock	Node only	Stubbed	Stubbed	Stubbed	N/A
LocalStack Community	Any	Yes	Yes	Yes	Yes (post-paywall, requires auth)

If you need multi-language, free, real Lambda triggers, depth-first conformance: fakecloud.