Practical overview
When it fits
Use Neow3J when the application stack is Java, Kotlin, Android or the JVM and the target ecosystem is Neo. Choose the SDK for dApp integration; choose the devpack and compiler when developing Neo N3 smart contracts.
Who it is for
- Java and Kotlin developers building Neo dApps.
- Android teams adding Neo blockchain functions to mobile applications.
- JVM developers integrating Neo nodes or constructing raw transactions.
- Smart-contract developers targeting Neo N3 with Java-based tools.
Documented uses
- Add Neo-specific SDK capabilities to Java, Kotlin, Android or JVM applications.
- Build software that interacts with Neo nodes and blockchain transactions.
- Construct raw Neo transactions in application code.
- Develop Neo N3 smart contracts with the devpack and compiler.
- Prepare and test a local Neow3J repository contribution.
Requirements & limits
The repository is public and licensed under Apache-2.0. The documented dependency examples use Maven or Gradle. Repository integration tests require Docker.
- The SDK covers Neo N3 and Neo Legacy releases, while the devpack and compiler are limited to Neo N3.
- The toolkit fits Java, Kotlin, Android and JVM projects rather than language-agnostic application stacks.
- Node integration and raw transaction support are identified capabilities for application developers.
- Repository contribution setup uses a Java 8 compilation target and a Gradle multi-project build.
- Docker is required for the repository’s integration-test workflow.
Check current requirements in the official documentation. Source-based guidance does not mean OpenViST has run or independently tested this project.
Add the Neow3J SDK to a Java or Kotlin project
Set up the documented Neow3J SDK dependency for Neo dApp development.
Before you start
- A Java, Kotlin, Android or JVM project.
- Gradle or Maven dependency management.
- A target Neo network choice: Neo N3 or Neo Legacy.
Steps
For Neo N3, add io.neow3j:contract at version 3.24.2 through Gradle or Maven.
For Neo Legacy, use the documented 2.4.0 SDK release.
Continue with the project’s Neo dApp implementation using the SDK.
Expected outcome
The project declares the Neow3J contract SDK dependency for Neo dApp development.
Guide limitations
- This recipe documents dependency setup only; it does not demonstrate a transaction, node connection or deployed application.
- The devpack and compiler are available only for Neo N3.
Prepare the Neow3J repository for contribution
Set up the repository environment described for building and testing Neow3J.
Before you start
- An installed JDK.
- Git and a fork of the public repository.
- Docker for integration tests.
Steps
Fork and clone the repository.
Create a branch from the main branch.
Use the repository’s Gradle build with Java 8 compilation settings; Gradle may download Java 8 if needed.
Run unit tests with ./gradlew test, or run integration tests with ./gradlew integrationTest when Docker is available.
Expected outcome
A contributor workspace is prepared and the repository’s documented test tasks can be invoked.
Guide limitations
- Integration tests require Docker to start a containerised blockchain node.
- The repository states that it has no Gradle task for automatic formatting or format validation.
- This is setup and test-command guidance, not a verification of successful execution.
Sources & review
Source record details
- Source availability
- Active
- Sources checked
- 3 October 2026
- Original website title
- neow3j/neow3j · Official homepage title · retained in its source language