TPAC 2025 High-Performance Baseline for Web Apps CG, MiniApps Ecosystem CG, MiniApps WG Joint Meeting
During W3C TPAC 2025, the W3C MiniApps Working Group, the High-Performance Web Apps Community Group, and the MiniApps Ecosystem Community Group held a joint session to review the latest progress on MiniApps specs. They also had deep-dive discussions on high performance Web apps, the role of MiniApps and the mobile Web in the AI era, and what the standards roadmap should look like going forward.
Towards a High-Performance Web
Yao Suibin from Tencent, who chairs the High-Performance Web Apps CG, pitched a “high-performance Web” vision, pointing out that the Web still has some fundamental weaknesses on mobile. Users tend to prefer native apps and cross platform frameworks, so if the Web wants to feel truly native, it needs some serious rework at the infrastructure layer to boost performance.
He suggested packaging Web apps as installable bundles, locking down dynamic JS execution, relying more on AOT compilation, and leaning on WebAssembly, WASI, and multithreading to improve performance and security across devices. The group also discussed using the WebAssembly component model and interface types to evolve both the UI and logic layers: on the UI side, moving away from heavy, traditional HTML elements toward template syntax and leaner components; on the logic side, compiling languages like AssemblyScript to WASM and opening the door for Rust, C++, Go, Python, and others to run on the Web, cutting JS memory and power overhead.
MiniApps in the age of AI
Yu Sen from Ant Group, a W3C TAG member and chair of the MiniApps WG, talked about how MiniApps can run across iOS, Android, HarmonyOS, in-car systems, and other “super apps,” giving developers a true “write once, run anywhere” experience. Under the hood, MiniApps are basically Web based DSLs plus tooling running on top of a custom runtime, which still needs to evolve in areas like rendering performance, multithreaded execution, and automated testing, as well as better use of GPU and NPU for AI scenarios.
On the AI interaction side, the discussion covered multimodal input, “generative UIs,” and new APIs for an “Agentic Web”: how to structure page and app data so agents can understand and operate MiniApps and Web apps, while still respecting permissions, security, and privacy boundaries.
Status of MiniApps standardization
Martin Alvarez Espinar from Huawei, who chairs both the MiniApps WG and CG, shared the status update: specs like MiniApp Lifecycle, Addressing, Manifest, Packaging, and Widgets are getting close to stable, but real world implementations and deployments are still quite limited, which is currently the biggest blocker. The group has been maintaining API and element “gap analysis” docs that compare what MiniApps can do in major super apps versus what the current Web platform supports out of the box.
Most MiniApp runtimes are built on top of WebViews, but these differ a lot in API surface, performance, and stability across platforms. That fragmentation is a key background factor for both standardization work and getting things to ship consistently in production.
How it plugs into the Web ecosystem
Participants stressed that MiniApps should not become some forked, “subset Web” that drifts away from the main Web platform. Instead, the idea is to use concepts like baselines and profiles to give concrete guidance for specific devices and scenarios, while still honoring the One Web principle. There was a strong push to work closely with TAG, OpenUI, Isolated Web Apps (IWA), the WebView CG, WebAI, and others to avoid reinventing the wheel around templating, packaging, sandboxing, and device APIs.
They also called out accessibility and semantics as must haves: custom markup and non DOM models shouldn’t break ARIA and related features. MiniApp runtimes are encouraged to reuse standard HTML elements and Web APIs wherever possible, and to validate behavior using shared test suites (like w3c/miniapp-tests) and data platforms such as caniwebview for baseline capability data.
MiniApps + IWA: good timing to team up
MiniApps and Isolated Web Apps (IWA) are very aligned in terms of isolated execution environments, app level packaging, and permission/security models. IWA’s work in WICG overlaps heavily with previous MiniApps standardization discussions, so there’s a good opportunity to move the Web forward together in this space.
The group suggested that the updated MiniApps WG charter should formally tighten collaboration with IWA and include a shared track for assessing where the Web is currently lacking in these areas, so that standards work can better support these new application models.
Deepening collaboration with the WebView CG
Since MiniApps on mobile mostly rely on system WebViews, their real world behavior is only as good as those WebViews. The WebView Community Group shared survey data showing big gaps in API coverage, performance, and interoperability, and emphasized how urgent it is to improve compatibility and stability.
Both sides agreed it makes sense for the MiniApps WG and WebView CG to jointly define a “WebView capability baseline” and a “gap analysis framework,” so there’s a measurable way to track and improve cross platform consistency. The plan is to explicitly include this collaboration in the next MiniApps WG charter.
Concrete next steps
The meeting landed on several follow up items:
- Put together a Web capability gap list (led by the High-Performance Web Apps CG) to identify core issues hurting mobile performance, cross device adaptability, and consistent UX, and then work with TAG, IWA, and others on fixes.
- Update the MiniApps WG charter with a clear collaboration model that spells out how the group works with IWA, the WebView CG, and others, to avoid duplicated efforts.
- Focus more on runtime ecosystems, app level packaging, permissions, and security models, and turn existing best practices into more generally applicable standard proposals.
Looking into the Future
With mobile and multi device ecosystems expanding fast, MiniApps have attracted a significant number of users. The general view was that MiniApps shouldn’t try to evolve in isolation, but instead grow together with the broader Web community to build a cross platform, reliable, and secure foundation.
Over the next few months, the group plans to push these action items forward, kick off the process to update the MiniApps WG charter, and open that up for public review, hoping to get more browser vendors, framework authors, and super app platforms involved.
More details in the meeting minutes.
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Text written by Wu Xiaoqian, minor editions by Martin Alvarez.