Application modernization services
Assess, upgrade, replatform and re-architect the applications your business runs on. Tools do the bulk rewrites. Senior engineers sign every change.
The short answer
Application modernization services move an aging application to a supported platform, current frameworks and an architecture you can change safely. Ace8 assesses first, writes tests, uses AI-assisted tools for the bulk rewrites, and has senior engineers verify each change. Production stays up because we cut over in small, reversible steps.
Scope
Ace8 works on enterprise Java estates: applications that run on WebLogic, WebSphere or JBoss EAP, on Java 8 or 11, on Spring 4 or 5, or as one large monolith that nobody wants to touch. We also move the databases and warehouses those applications depend on.
We do not start with a target. We start with an inventory of what you run, how much of it is tested, and what it costs to keep. The target platform follows from that.
Choosing a path
The five common paths are rehost, replatform, refactor, re-architect and replace. They are not a ladder you must climb. Most estates use three or four of them, one per application. The assessment picks the path for each application using the questions below.
| Path | What changes | Fits when | Watch for |
|---|---|---|---|
| Rehost | Where it runs, not the code | The app is stable, tested and the sole issue is the data center or contract | The licence and the old runtime come with it |
| Replatform | The runtime or app server | Business logic is sound but the app server or Java version is the cost or the risk | Server-specific features such as JMS, JNDI and clustering |
| Refactor | Code inside the existing design | The design holds but the code uses removed APIs, old frameworks or has no tests | Thin test coverage, which we fix first |
| Re-architect | The design itself | A monolith blocks releases or scaling, and the seams are clear | A rewrite disguised as a migration |
| Replace | The whole application | A package or SaaS product covers the need and the custom code adds no advantage | Data migration and retraining cost |
Service lines
Each line below has a page that goes deep on its tools, its risks and its order of work.
Architecture
Splitting a monolith into services is a means, not a goal. We recommend it where a single capability changes often, scales differently from the rest, or blocks releases. We recommend against it where the cost of distributed systems exceeds the benefit.
Where a split is justified, we use the strangler approach. One capability moves behind a stable interface, the old and new versions run side by side, and traffic shifts when the new one has proven itself. Containerizing a Java application for Kubernetes follows the same logic: after the runtime is current and the configuration is externalized, not before.
Messaging often sits at the seam between old and new. The AceMQ engineering team has done this work with RabbitMQ, which is why the American National case study is part of the evidence on this page.
Data
Applications and their databases age together. A Java upgrade that leaves the application on a proprietary database moves the cost without removing it. We scope the data layer in the same assessment as the application.
Typical moves are Oracle to PostgreSQL, and warehouse migrations off Teradata and Netezza. For Greenplum we frame the decision as stay, upgrade or exit, because for some teams staying is the right answer, and AceMQ supports that path.
The same rules apply as for code: baseline first, move in slices, keep a rollback for every step, and land on an open target.
Method
Read the full method and the AI-assisted approach.
We write characterization tests that pin down what the application does today.
OpenRewrite recipes and AI-assisted tools make the repetitive edits in small slices.
The same tests run before and after. A failing test stops the slice.
Each diff is reviewed by a person who is accountable for it. Output that fails review is rewritten by hand.
Pricing
Every engagement starts with a fixed-price assessment, and phase one is priced from its findings. We do not publish ranges yet because we have not quoted enough engagements to publish honest ones. We can show you what moves the price.
After go-live
Ace8 is the modernization practice of AceMQ. When the work goes live, AceMQ supports the new stack 24/7, including Tomcat, Java, Spring, RabbitMQ and Kafka. We write the run plan before cutover. See supported after migration.
Architecture
Re-architect where the system needs it, not by default.
Data
Move the data layer off closed or end-of-life platforms.
Plan
For the business case and the vendor choice.
Proof
The messaging layer was replaced in phases while the applications that called it were refactored. There was no big-bang cutover.
After go-live
The five common ones are rehost, replatform, refactor, re-architect and replace. Most estates use several, one per application. The assessment scores each application and recommends a path, so the choice rests on test coverage, framework age and coupling rather than preference.
It depends on the number of applications, their size and how well they are tested. The assessment gives a phased roadmap with effort ranges, so you see the timeline before you commit to phase one.
Rarely. A rewrite is the highest-risk path. We prefer to change code in small slices behind tests, and we re-architect where the assessment shows a clear payoff.
Open targets: Tomcat, Spring Boot, Jakarta EE, Kubernetes and PostgreSQL. We avoid landing you on another proprietary platform.
Tools such as OpenRewrite and AWS Transform make the repetitive edits. A senior engineer reviews and signs every change. AI drafts; engineers decide.
AceMQ does, 24/7, for Tomcat, Java, Spring, RabbitMQ and Kafka. The run plan is written before cutover.
A fixed-price assessment gives you the inventory, the risk score and a phased plan. Scope and cost are fixed before the migration starts.
Book a Fixed-Price AssessmentGet in touch
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