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Fix(diagrams): D2 diagrams draw on iPhone and in Safari - #959
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@terrastruct/d2 starts its Go compiler in a module worker. In WebKit (the iPhone app's WKWebView, Safari on the self-hosted web app) the Go runtime overflows the worker's smaller stack while it starts: the WebAssembly loads, the worker still reports ready, and every d2 fence then failed with "undefined is not an object (evaluating 'd2.compile')". The same runtime starts fine on the page's own thread. createD2 now asks the package's worker for its version first. Chromium (the desktop app, Android, Chrome on the web app) answers and keeps the worker, so nothing changes there. When the worker cannot answer, the worker script the package builds runs on the page instead: its Blob is read as text while the D2 is constructed, its two module exports are dropped, and its message handler is given an in-page port. Nothing fetches or imports a blob URL, so the self-hosted server's Content-Security-Policy (script-src 'self' 'unsafe-eval') allows it as it is. The Go runtime's process and path stubs leave the page once it has started, so no library mistakes the page for Node; fs stays, since the runtime writes its output through it. It deliberately does not patch the package or move the compiler for everyone: a compile on the page holds the UI while it runs, which only WebKit has to accept. A package update whose worker script no longer ends the way this expects fails loudly instead of running something else, and a test pins that against the installed version. Checked in a WKWebView under the server's exact policy (two diagrams compiled and rendered; the unfixed path fails on the same page) and in Chromium, where the worker still does the work and nothing lands on the page.
3d6feed lets D2 diagrams draw in WebKit, so the shared packages move to 2.71.1 and the prepared iPhone 1.27.0 adopts that instead of 2.71.0. The self-hosted web client gets it with the next server pin. Android 1.1.41 ships on 2.71.0, where D2 already draws, and the desktop app stays at 2.71.0 until its next release.
adibhanna
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Oct 19, 2026
Core core-2.71.1-core.h77db37926ce01390, built by CI from ZenNotes/zennotes ae288166 (main, ZenNotes/zennotes#959); core:adopt checked SHA-256, SHA-512, packed versions and clean-source provenance. On 2.71.0 every d2 fence here showed "undefined is not an object (evaluating 'd2.compile')": WebKit gives a worker a smaller stack than the Go runtime inside the D2 compiler needs while it starts, so the worker reported ready with no compiler. Core 2.71.1 asks the worker for its version first and, when it cannot answer, runs the same compiler on the page, where it starts fine. Chromium keeps the worker, so the desktop and Android do not change. Checked in a WKWebView on this build: the demo tour's D2 architecture diagram and a Mermaid flowchart both draw in the same note, with no diagram error. 265 tests, typecheck, boundary check and Capacitor sync pass.
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D2 diagrams failed in WebKit (the iPhone app, Safari on the self-hosted web app): the Go runtime overflows the worker's stack while it starts, so every d2 fence showed "undefined is not an object (evaluating 'd2.compile')".
createD2probes the package's worker withversion(). Chromium answers and keeps the worker, unchanged.processandpathstubs are removed from the page once it has started.Verified in a WKWebView under the server's exact CSP (the unfixed path fails on the same page) and in Chromium (worker path, nothing on the page). New tests pin the script rewrite against the installed
@terrastruct/d2.