Sample Projects

Specmatic in Action: Sample Projects

Specmatic unlocks a new way to approach microservices by aligning contracts and code, making your systems reliable and resilient. Our sample projects showcase real-world implementations across various technologies and communication protocols. This is your playground to experience Specmatic.

Sample Application Architecture

Each sample project is designed around a familiar microservices setup, giving you the clarity and confidence to integrate Specmatic seamlessly into your stack.
The architecture consists of three core components:

1. Backend Service – The system's engine, processing and providing data.
2. BFF (Backend For Frontend) – A mediator between the frontend and backend services.
3. Frontend Application – Where the user interacts.

Let's discover how Specmatic works across different layers of an app, with help of following sample projects.

Sample Projects

OpenAPI

Projects

Layer	Language	Framework	Sample Project
Backend	Kotlin	Spring Boot	specmatic-order-api-java
Backend	NodeJS	Express	specmatic-order-api-nodejs
Backend	Python	Flask	specmatic-order-api-python
Backend	C#	.NET	specmatic-order-api-csharp
Back-end for Front-end (BFF)	Kotlin	Spring Boot	specmatic-order-bff-java
Back-end for Front-end (BFF)	NodeJS	Express	specmatic-order-bff-nodejs
Back-end for Front-end (BFF)	Python	Flask	specmatic-order-bff-python
Back-end for Front-end (BFF)	Python	FastAPI	specmatic-redis-python-sample
Back-end for Front-end (BFF)	Python	Sanic	specmatic-order-bff-python-sanic
Back-end for Front-end (BFF)	GoLang	Gin	specmatic-order-bff-go
Back-end for Front-end (BFF)	C#	.NET	specmatic-order-bff-csharp
Frontend	JS	React	specmatic-order-ui-react

Security Schemes

Security	Language	Framework	Sample Project
OAuth	Kotlin	Spring Boot	specmatic-order-api-java-with-oaut

Other Projects

Name	Language	Sample Project
specmatic-hooks-java-sample	Kotlin	specmatic-hooks-java-sample

Converting existing mocks to Specmatic

Convert from	Sample Project
Wiremock	wiremock-to-specmatic

AsyncAPI

Projects

Protocol	Interaction Pattern	Language	Framework	Sample Project
Kafka	Fire-n-Forget	Kotlin	Spring Boot	specmatic-order-bff-java
Kafka	Fire-n-Forget	NodeJS	Express	specmatic-order-bff-nodejs
Kafka	Request-Reply	Kotlin	Spring Boot	specmatic-kafka-sample
JMS	Request-Reply	Kotlin	Spring Boot	specmatic-order-bff-jms

Schema Registries

Schema Registry	Language	Framework	Sample Project
Avro (Kafka)	Kotlin	Spring Boot	specmatic-kafka-avro-sample

gRPC

Projects

Layer	Language	Framework	Sample Project
Backend	Kotlin	Spring Boot	specmatic-order-api-grpc-kotlin
Back-end for Front-end (BFF)	Kotlin	Spring Boot	specmatic-order-bff-grpc-kotlin
Back-end for Front-end (BFF)	GoLang	Gin	specmatic-order-bff-grpc-go

GraphQL

Projects

Layer	Language	Framework	Sample Project
Front-end	JS	React	specmatic-order-graphql-ui-react
Back-end for Front-end (BFF)	Kotlin	Spring Boot	specmatic-order-bff-graphql
Backend Consumer	Java	Spring Boot	specmatic-order-graphql-consumer

JDBC

Projects

Layer	Language	Framework	Sample Project
Backend	Kotlin	Spring Boot	specmatic-jdbc-sample

Redis

Projects

Layer	Language	Framework	Sample Project
Backend	Kotlin	Spring Boot	specmatic-redis-sample
Back-end for Front-end (BFF)	Python	FastAPI	specmatic-redis-python-sample

WSDL

                                      PRODUCTION SETUP
+-------------------+         +--------------------------+         +-------------------+
|                   |         |                          |         |                   |
|  WSDL SOAP Client |         |  Product BFF Search      |         |  order_api        |
|                   |         |  Service (BFF)           |         |  (WSDL Service)   |
+---------+---------+         +-----------+--------------+         +---------+---------+
          |                               |                                  |
          | 1. Request (SOAP)             |                                  |
          +------------------------------>|                                  |
          |                               |                                  |
          |                               | 2. Request (SOAP)                |
          |                               +--------------------------------->|
          |                               |                                  |
          |                               |                3. Response (SOAP)|
          |                               |<---------------------------------+
          | 4. Response (SOAP)            |                                  |
          +<------------------------------+                                  |

                                        CONTRACT TEST SETUP
+-------------------------+         +--------------------------+         +----------------------+
|                         |         |                          |         |                      |
| Specmatic Contract Test |         |  Product BFF Search      |         |  Specmatic Mock      |
|   (WSDL of BFF)         |         |  Service (BFF)           |         |  (WSDL of order_api) |
+-----------+-------------+         +-----------+--------------+         +----------+-----------+
            |                                   |                                   |
            | 1. Request (SOAP)                 |                                   |
            +---------------------------------->|                                   |
            |                                   |                                   |
            |                                   | 2. Request (SOAP)                 |
            |                                   +---------------------------------->|
            |                                   |                                   |
            |                                   |                3. Response (SOAP) |
            |                                   |<----------------------------------+
            | 4. Response (SOAP)                |                                   |
            +<----------------------------------+                                   |
            |
            |--------------------+
            | 5. Assert response |
            | against WSDL spec  |
            +<-------------------+

Projects

Layer	Language	Framework	Sample Project
Back-end for Front-end (BFF)	Kotlin	Spring Boot	specmatic-order-bff-wsdl

Arazzo

Projects

Specification	Language	Framework	Sample Project
OpenAPI	Python	Flask	specmatic-arazzo-sample
OpenAPI + AsyncAPI	Python	Flask	specmatic-arazzo-async-sample
OpenAPI with Consumer	Python	Flask	specmatic-arazzo-ui-sample

MCP

Projects

MCP Server	Sample Project
Postman	mcp-auto-test
HuggingFace	mcp-auto-test

Central Repo

Projects

Name	Repository
Specmatic Order Contracts	specmatic-order-contracts

Bringing It All Together

By exploring these projects, you'll gain hands-on experience in integrating Specmatic with a variety of technologies, giving you the power to build smarter and more resilient systems.

Need Help?

• Join our community discussions for discussions and support
• Report bugs or suggest improvements in our GitHub repository
• Reach out directly—we're here to help!

Contributing

We welcome contributions! If you've built something interesting with Specmatic:

• Submit a pull request to add your example
• Share your implementation of these samples in different frameworks
• Help us improve documentation and examples

Ready to transform how you build and test microservices? Pick a sample project and start your Specmatic journey today!