v0.1.3 | Lands the `deno_core` 0.408 bump deferred from 0.1.2 — a V8 isolate must now be constructed inside an entered tokio runtime or the process aborts — and makes the V8 heap ceiling environment-tunable.

Fixed

• A V8 isolate constructed outside a tokio runtime aborted the process
  (#37). deno_core
  0.408 captures tokio::runtime::Handle::try_current() when it registers an
  isolate and spawns V8's delayed foreground tasks — GC memory-reducer work —
  on that handle; with no handle it prints a diagnostic and calls
  std::process::abort(). The synchronous constructors
  (BrowserJsRuntime::new / with_profile / with_options) are public API
  callable from a plain fn main or a #[test], so they now enter a
  process-lifetime fallback runtime when the caller has none. Applies to both
  the page and worker realms.

  Worth being precise, because it shaped the 0.1.2 release: the abort is
  not debug-gated and not platform-specific. Release builds passed only
  while V8 happened not to post a delayed task inside the window under test —
  i.e. a latent production abort, which is why the bump was held back from
  0.1.2 rather than shipped. Reproduced on Linux, macOS and Windows.

Added

• Environment-tunable V8 heap limits. The right ceiling is a property of
  the deployment, not of the engine, and the previous hard-coded 4 GB silently
  over-committed small containers.

  • BROWSER_OXIDE_HEAP_MAX_MB — default 4096 (4 GB)
  • BROWSER_OXIDE_HEAP_INITIAL_MB — default 1024 (1 GB)

  Unparseable or zero values fall back to the defaults with a warning rather
  than failing; an initial above the ceiling is clamped, since V8 rejects that
  pairing. Both are per-isolate, so a PagePool of N pages can commit up
  to N × the ceiling — see docs/CONFIGURATION.md.

Dependencies

• deno_core 0.404 → 0.408 (V8 149.2.0 → 149.4.0), the bump deferred from
  0.1.2.

Changed

• CI runs cargo test with --nocapture. Not cosmetic: libtest captures each
  test's output and replays it only on failure, so when a test aborts the
  reason dies with it. That is why #37 first surfaced as a bare
  signal: 6, SIGABRT with no diagnosis. Any future abort-on-construction
  would otherwise be undiagnosable from CI logs alone.

Verified

• Canvas fingerprint byte-identical across the V8 bump —
  examples/canvas_fp_probe.rs reports len=17502 fnv1a=5b1d42ee9bdc9713, the
  same value as 0.1.1 and 0.1.2.
• Real-site regression vs main, 15 open sites, both engine paths: zero
  regressions; the warm-reuse fix from 0.1.2 still holds (pool 11/15 → 12/15).
• Full CI matrix green on ubuntu (stable/beta/nightly), macOS and Windows —
  including the debug jobs that previously aborted.

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Installation

Rust (crates.io)

cargo add browser_oxide

Python (PyPI)

pip install browser-oxide

MCP Server (for AI assistants)

cargo install browser_oxide_mcp

Or download a pre-built browser-oxide-mcp binary for Linux, macOS, or Windows
from the assets below.

Platform Support (MCP binary)

Platform	Architecture	Archive
Linux	x86_64 (glibc)	browser-oxide-mcp-x86_64-unknown-linux-gnu.tar.gz
macOS	ARM64 (Apple Silicon)	browser-oxide-mcp-aarch64-apple-darwin.tar.gz
macOS	x86_64 (Intel)	browser-oxide-mcp-x86_64-apple-darwin.tar.gz
Windows	x86_64	browser-oxide-mcp-x86_64-pc-windows-msvc.tar.gz

Changelog

See CHANGELOG.md for full details.