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Ocean View Games
Ocean View
Games
Legacy Game Modernisation

Legacy Game Modernisation

Flash to HTML5. Java to Unity. We reverse-engineer, rebuild, and relaunch games from obsolete platforms.

Breathing New Life Into Classic Games

Flash is dead. Old Unity versions break. App stores delist non-compliant builds. Java applets no longer run in browsers. If your game or interactive content is stuck on an obsolete platform, we can bring it back to life. We specialise in rescuing legacy titles, including cases where the original source code has been lost entirely. Our team's preservation experience includes rebuilding the Museum of London's Great Fire of London educational game from a published SWF file with no source code available (during David's time at fish in a bottle), and reconstructing Inferna Games' Nub from its original native Java source into Unity for cross-platform deployment. Whether your content was built in Flash, an older version of Unity, native Java, or another legacy platform, we preserve the gameplay your audience depends on while modernising everything underneath: browser compatibility, mobile responsiveness, accessibility, and platform compliance.

Our Modernisation Services

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Flash to HTML5 Conversion

Full-fidelity ports of Flash games to HTML5/WebGL, preserving animations, interactivity, and game logic for modern browsers and mobile devices.

⬆️

Legacy Unity Upgrades

Systematic upgrades across major Unity versions - fixing obsolete APIs, deprecated packages, and broken physics/lighting for a stable modern LTS build.

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Codebase Recovery & Rebuild

When source code is lost, we decompile existing builds to recover assets and reconstruct the game in a modern engine like Unity.

♿

Accessibility Modernisation

Updating UI for modern aspect ratios, adding touchscreen support, and implementing accessibility features that weren’t standard when the game was first released.

📲

Store Re-Listing & Compliance

Bringing delisted games back to the App Store and Google Play by meeting current requirements: 64-bit compliance, API levels, GDPR, and ATT policies.

Types of Modernisation Projects We Handle

"Legacy modernisation" covers a wide range of starting points. Some clients come to us with a Flash game that no longer runs in any browser. Others have a working Unity project that needs upgrading before they can ship their next update. The scope and approach differ significantly depending on where you are starting from. Below are the five most common modernisation scenarios we handle. If your situation does not fit neatly into one of these, get in touch and we will assess your project individually.

Flash to HTML5 Conversion

Rebuilding Flash and ActionScript games as modern HTML5 or Unity WebGL applications. We preserve the original game design and player experience while replacing the technology stack entirely. For educational Flash content, we maintain LMS integration with SCORM and xAPI compatibility. The rebuilt content runs natively in Chrome, Safari, Firefox, and Edge with no plugins required. We cover this in depth in our Flash to HTML5 migration guide.

Unity Version Migration

Upgrading projects from older Unity versions (2018, 2019, 2020, 2021) to Unity 6. This includes resolving deprecated API usage, plugin compatibility issues, and rendering pipeline changes (Built-in to URP or HDRP). We update build pipelines for current iOS and Android SDK requirements and take advantage of performance improvements available in newer Unity versions: GPU Resident Drawer, improved batching, and Addressables for asset management. Not sure whether your project needs a migration? Assess your risk with our free Unity Migration Checker.

Engine Migration

Moving projects from legacy or discontinued engines to Unity. This includes porting from custom or proprietary engines to a supported commercial engine, and evaluating whether to port existing code or rebuild from scratch. In many cases, a clean rebuild in Unity is faster and cheaper than line-by-line porting, especially when the original engine's architecture does not map well to Unity's component model. Our Engine Comparison tool can help evaluate target engine options for your project.

Codebase Overhaul (Same Engine)

Not every modernisation project involves changing engines. Sometimes the game runs on a current engine but the codebase itself has become unmaintainable. We refactor monolithic codebases into modular architectures, replace deprecated networking stacks (UNet to FishNet or Mirror), implement automated testing where none exists, and address technical debt that is blocking new feature development. Performance optimisation is included as part of the modernisation engagement rather than being treated as a separate project. See our Performance Optimisation service for standalone performance work.

Platform Modernisation

Updating games to meet current App Store and Google Play requirements including SDK levels, privacy manifests, and data safety declarations. We also add platform support that did not exist when the game was originally built, such as bringing a PC-only game to mobile, or preparing a mobile title for console certification. Check your platform readiness with our Platform Readiness Checklist, or use the Porting Feasibility Checker to assess whether adding a new platform is viable for your project.

Our Modernisation Process

Modernisation is not a chaotic "open the bonnet and see what happens" exercise. We follow a structured four-phase process designed to minimise risk, control costs, and give you clear visibility at every stage. Every modernisation project begins with a paid technical audit, so you know exactly what you are getting into before committing to the full engagement.

Step 1: Technical Audit

A full codebase review covering architecture assessment, dependency inventory, and deprecated API usage scan. We check plugin and middleware compatibility against your target platform or engine version, run performance profiling on the current build to establish baseline metrics, and compile a risk register: what will break, what might break, and what is safe. Deliverable: A written audit report with scope estimate, recommended approach, timeline, and fixed-price quote for the full modernisation. This audit is a standalone deliverable. If you decide not to proceed, you keep the report and can use it to brief another team.

Step 2: Migration Planning

Based on the audit findings, we plan the migration in detail. This includes deciding between incremental upgrade (version by version) and clean rebuild, identifying the critical path (which systems must be migrated first), setting up parallel builds so the live version is unaffected during migration, and defining test criteria for verifying the modernised version matches the original.

Step 3: Execution

Iterative migration with regular playable builds for comparison testing. We use automated regression testing where possible and test platform-specific builds on real devices throughout the process, not just at the end. You receive regular progress reports and have check-in points to review the modernised build against the original.

Step 4: Verification and Handover

Side-by-side comparison testing between the original and modernised versions. Performance benchmarking against the audit baseline ensures the modernised build meets or exceeds the original. If applicable, we handle platform submission (App Store, Google Play, Steam). Deliverables: Documentation of all changes, new dependencies, and updated build procedures. If your team will maintain the project going forward, we provide knowledge transfer sessions covering the new architecture, build pipeline, and any areas that require ongoing attention.

Why Games Need Modernisation

If you are evaluating whether modernisation is worth the investment, you are not alone. Most clients come to us having deferred the decision for months or years, hoping the problem would resolve itself. It does not. Here are the five most common reasons legacy games reach a point where modernisation becomes unavoidable.

Platform Requirements Change

Apple and Google update SDK requirements annually. A game built on Unity 2019 may not be able to target the required Android API level or include the mandatory iOS privacy manifest. Without updating, you cannot submit updates to the stores. This deadline moves every year, and catching up becomes harder the longer you wait.

Plugin Ecosystems Move On

Third-party plugins drop support for older engine versions. A critical security patch or platform compatibility fix may only be available for newer versions, forcing an unplanned migration under time pressure. Planned migrations are always cheaper and less disruptive than emergency ones.

Technology Becomes Unsupported

Flash is the most dramatic example, reaching end of life in December 2020, but engine versions also leave LTS support windows. Running on an unsupported engine version means no security patches and no bug fixes from the engine vendor. You are on your own.

Performance Expectations Rise

Devices get faster, but player expectations rise faster. A game that ran acceptably on a 2019 flagship may feel sluggish on a 2026 mid-range device because the OS, browser, or platform runtime has changed. Modern engine versions include optimisations (GPU Resident Drawer, improved batching, better memory management) that can deliver significant performance gains with relatively modest migration effort.

New Features Require Modern Foundations

Adding multiplayer, analytics, monetisation, or accessibility features to a legacy codebase is often harder than modernising first and then adding features to a clean foundation. If your roadmap includes new capabilities, modernisation is not a cost but a prerequisite.

Our Modernisation Track Record

We do not just talk about legacy modernisation in the abstract. Here are specific examples from our portfolio and our team's experience that demonstrate the range of modernisation work we handle.

Domi Online: Live MMORPG Unity Migrations

Domi Online is a live MMORPG with active players. We have managed ongoing Unity version migrations across multiple major releases while the game remains in operation. The zero-downtime migration approach uses parallel build verification to ensure each upgrade is stable before it reaches players. This project demonstrates that even complex, live-service games can be modernised systematically without disrupting the player base.

RuneScape: Modernising a 20-Year-Old Codebase

Our founder David's experience at Jagex included contributing to the migration of RuneScape's Java client to a modern C++ client while maintaining backward compatibility with two decades of game content. This is one of the largest and most complex game modernisation projects in the industry, involving millions of lines of legacy code and an active player community of hundreds of thousands. Read more about this experience in our RuneScape porting case study.

Educational Game Modernisation

Our team has modernised legacy Flash-based educational games to HTML5 with LMS integration preserved. The Great Fire of London project (during David's time at fish in a bottle) is the most dramatic example: the original source code had been lost entirely, and the team reverse-engineered the complete experience from a published SWF file. For organisations with educational Flash content, modernisation preserves the curriculum alignment and learning outcomes that took years to develop. Further reading: Flash to HTML5 Migration Guide

Flash to HTML5 Conversion

Adobe ended Flash support in December 2020 and every major browser has removed it. If your organisation still has interactive content built in Flash, whether that's educational games, training simulations, museum exhibits, or marketing interactives, your users can no longer access them. For most organisations, this isn't just a technical inconvenience. That Flash game might represent years of curriculum development, significant original investment, or an irreplaceable educational resource that teachers and learners still depend on. Walking away from it isn't an option. Rebuilding from scratch with a new design team is expensive and unnecessary. We convert existing Flash content to HTML5 or Unity, preserving the original gameplay, design, and learning outcomes while making it work on every modern browser, tablet, and phone.

With Source Code

If you have the original .fla or .as source files, conversion is relatively straightforward. We analyse the ActionScript codebase, map the game logic and asset dependencies, and rebuild the equivalent systems in HTML5 (Canvas/WebGL) or Unity (targeting WebGL export). Original art assets, animations, and audio can often be extracted and reused directly, significantly reducing cost and timeline.

Without Source Code

If your source code has been lost, which is more common than most organisations expect, we reverse-engineer the published .swf file. We decompile the SWF to recover asset structures, analyse the gameplay through systematic playtesting, and reconstruct the logic from observed behaviour. This is exactly what was done for the Museum of London's Great Fire of London game: the original source had been lost entirely, but the team rebuilt the complete experience in HTML5 from the published SWF alone. Read the Fire of London Case Study →

HTML5 or Unity? Choosing the Right Target

HTML5 (Canvas / WebGL)
Best for browser-only deployment, lightweight games, and institutional content that needs to run without installation. No app store submission required, works on Chromebooks and managed devices, and delivers smaller file sizes. Less suitable for complex 3D graphics or heavy physics. Unity (WebGL Export)
Best for complex games, 3D content, and projects that may later need iOS, Android, or desktop versions. Richer graphics, cross-platform deployment from a single codebase, and access to Unity's full feature set. Larger download size and longer initial load in browser. We advise on the best option during the assessment phase based on your content complexity, target devices, and future platform needs.

What We Preserve and What We Improve

Preserved

  • ✓
    Original gameplay mechanics and game feel
  • ✓
    Visual design, art style, and character animations
  • ✓
    Audio, sound effects, and music
  • ✓
    Story, narrative flow, and level progression
  • ✓
    Scoring systems, leaderboards, and save states
  • ✓
    Educational content, quiz logic, and learning outcomes

Improved

  • ⬆
    Mobile support

    Touch controls, responsive layouts, Safe Area UI for notches and tablets

  • ⬆
    Accessibility

    Screen reader support, keyboard navigation, colour-blind modes, adjustable text size, WCAG 2.1 compliance

  • ⬆
    Browser compatibility

    Works on Chrome, Safari, Firefox, and Edge without plugins

  • ⬆
    Performance

    Faster load times, smaller file sizes, no plugin overhead

  • ⬆
    LMS integration

    SCORM/xAPI compliance for tracking learner progress

  • ⬆
    Analytics

    Player behaviour tracking, completion rates, engagement metrics

  • ⬆
    Security

    No Flash vulnerabilities, GDPR-compliant data handling, HTTPS by default

  • ⬆
    Multi-language support

    Internationalisation architecture for localised content

Why Choose Us?

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Reverse-Engineering Experts

Lost your source code? We can decompile existing builds to recover assets and reconstruct game logic in a modern engine - no original project files required.

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Flash-to-HTML5 Specialists

We port end-of-life Flash games to HTML5/WebGL or Unity so they remain playable in modern browsers and on mobile devices without plugins.

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Gameplay Preservation

Our goal is to preserve the original game feel 1:1 while modernising UX for today’s screens, input methods, and accessibility standards.

Legacy Tech Stack

Bridging the gap between vintage code and modern screens:

Adobe Flash Platform Logo
Flash
Unity Game Engine Logo
Unity
WebGL Web Graphics Library Logo
WebGL
HTML5 Web Standard Logo
HTML5

Who Needs Legacy Game Modernisation

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Museums & Cultural Institutions

You have interactive exhibits, educational games, or gallery installations built in Flash that visitors can no longer access. These experiences often represent significant curatorial and educational investment. We rebuild them for modern browsers and touchscreen kiosks without losing the original design intent.

See our work for museums →
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Universities & Schools

Your curriculum includes Flash-based learning games, simulations, or assessment tools that teachers and students still rely on. Replacing them with off-the-shelf alternatives means losing the curriculum alignment you spent years developing. We convert them to HTML5 with LMS integration so they work in your existing digital learning environment.

See our work for education →
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Publishers

You have a catalogue of Flash-based interactive content: children's games, language learning tools, or supplementary educational materials. Converting to HTML5 extends the commercial life of content you've already paid to develop, reaching mobile and tablet audiences that Flash never could.

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Corporate Training Teams

Your onboarding, compliance, or skills training includes Flash-based modules that your LMS can no longer serve. Rebuilding in HTML5 with SCORM or xAPI compliance means your existing training content keeps working without restarting the instructional design process from scratch.

See our work for corporate training →
🎮

Game Studios

You have a legacy game with an active player community that can no longer access it, whether it's a browser-based game, a delisted mobile title, or an older Unity project that no longer compiles. We can port it to HTML5 or modern Unity to keep your players engaged and your content accessible.

See our work for game studios →

Our Game Preservation & Upgrade Workflow

Modernising a legacy game is like restoring a classic car. We carefully dismantle the old build, salvage the core components, and rebuild them on a modern engine chassis that can run for another decade.

1. Forensic Audit & Recovery

If the source code is lost, we start with “Digital Archaeology.” We use advanced decompilation tools to extract assets and logic directly from the final build (SWF, APK, or EXE).

  • Decompilation: Using tools like ILSpy or DnSpy to view the original logic inside compiled binaries.
  • Asset Extraction: Recovering original sprites, audio files, and data tables that are locked inside old formats.
  • Feasibility Report: We deliver a roadmap detailing exactly what can be saved and what needs to be rewritten.

2. Engine Reconstruction

We port the logic into a Long-Term Support (LTS) version of Unity. We don’t just wrap the old game; we rebuild the architecture to ensure stability.

  • Logic Porting: Translating ActionScript (Flash) or legacy C++ into clean, modern C# scripts.
  • Bug Fixes: Squashing the decades-old bugs that plagued the original release.
  • Performance Tuning: Optimising the code so the game runs at a smooth 60 FPS on mobile devices, not just high-end PCs.

3. Asset Upscaling & Restoration

Old games often look blurry on modern 4K screens. We enhance the visuals without losing the nostalgic charm.

  • AI Upscaling: Using neural networks to sharpen low-resolution textures and backgrounds.
  • Vectorisation: Converting Flash vector art into crisp SVG or Unity sprites that scale infinitely.
  • UI Redesign: Rebuilding menus to support wide-screen aspect ratios (16:9 or 19.5:9) instead of the old 4:3 box.

4. Modern Compliance & Deployment

The final step is ensuring the game survives the modern app store ecosystem.

  • Input Modernisation: Adding touch-screen gestures, virtual joysticks, or controller support to mouse-only games.
  • Safe Area Implementation: Ensuring UI elements don’t get hidden behind the “Notch” or “Dynamic Island” on modern phones.
  • 64-Bit Compliance: Delivering the mandatory technical updates required by Google Play and the Apple App Store to prevent delisting.

Legacy Modernisation in Practice

The Great Fire of London

Flash to HTML5, No Source Code • via fish in a bottle

The Museum of London's educational game about the Great Fire of London was built in Flash to commemorate the 350th anniversary. When Flash reached end-of-life, the game became inaccessible to the schools and learners who depended on it. The original source code had been lost entirely. During David's time at fish in a bottle, the team reverse-engineered the published SWF, decompiled it to recover asset structures, reconstructed the gameplay logic through systematic analysis, and rebuilt the entire experience in HTML5. The result is fully responsive across desktop and mobile, accessible to WCAG standards, and still in active use by the museum today.

Flash to HTML5No Source CodeEducationalMuseum of London
Read Full Case Study

Nub

Java to Unity Platform Migration

Inferna Games' Nub was an isometric puzzle game originally built as a native Java app for the Ouya Android console. When the Ouya platform failed, the game needed to reach iOS, Android, and Steam. Porting the native Java codebase directly was impractical, so Ocean View Games rebuilt the game from the ground up in Unity using the original Java source as a reference, enabling cross-platform deployment and mobile-optimised controls.

Java to UnityPlatform MigrationCross-Platform
Read Full Case Study
View All Case Studies →

What Does Legacy Modernisation Cost?

Costs depend on the complexity of the original content, whether source code is available, and what modern features need to be added.

Simple Interactive Content

From £3,000 to £8,000

Quizzes, slideshows, basic Flash animations. Straightforward logic, limited interactivity, source code available or simple enough to reverse-engineer quickly.

Medium-Complexity Games

From £8,000 to £25,000

Educational games with multiple levels, scoring, basic physics. This is where most institutional Flash games and older Unity projects fall, including curriculum-aligned learning games with 5 to 15 activities or levels.

Complex Games

From £25,000 to £60,000+

Multiplayer, persistent save states, extensive content, no source code, full engine migration. Projects like the Great Fire of London sit in this range due to the reverse-engineering requirement and the breadth of interactive content.

Legacy Unity Upgrades

From £5,000 to £30,000

Upgrading from older Unity versions (e.g. Unity 5 to Unity 6 LTS) depending on project size, the number of deprecated APIs, and whether third-party plugins need replacing.

All quotes are fixed-price with milestone-based payments. We provide a detailed technical assessment and quote within one week of receiving your legacy content. Get a Free Assessment →

Don’t let your classic game die. We’ll bring it back to life on modern platforms.

Book a Technical Consultation

What Our Clients Say

“David did a great job with the project and was able to take a great amount of autonomy. There was very little need to go back and forth and ask him to change anything. His code is also very clean. He laid out his own roadmap plans and worked well with the rest of the team.”
Walden Yan

Walden Yan

GameFi

“Awesome job! I really look forward to working with the guys again very soon!”
Jacob B

Jacob B

Chief Creative Officer, Foil Hat Games

Assess Your Project

Free interactive tools to help scope your project.

Check Unity migration readinessFind out whether your Unity project needs a version migration and what risks to expect.Try it free →Check porting feasibilityThinking about adding a new platform? Assess feasibility before committing.Try it free →Compare game enginesEvaluating a new engine for your rebuilt project? Compare Unity, Unreal, Godot, and more.Try it free →
Read: Flash to HTML5 Migration Guide →View all development services →Educational games service →

Don’t Let Your Classic Game Die

Send us your legacy files (SWF, APK, old Unity project, or just a URL where the content used to live) and we'll come back within one week with a technical assessment, conversion options, and a fixed-price quote.

Get a Free Assessment