Issues

• IO.args turns non-UTF-8 arguments into U+FFFD, so a program can't open a file it was given

  bendlang/bend#1798 · Filter by author viridale opened on Oct 20, 2026

• IO.get_env with a "=" in the name reads part of another variable on the C lane and Node

  bendlang/bend#1794 · Filter by author orezraey opened on Oct 20, 2026

• Device lane spill: a loop at the exact fill depth spills and restores the whole stack on every call (~200x slower)

  bendlang/bend#1790 · Filter by author Lorenzobattistela opened on Oct 20, 2026

• Base: read a number from a string (U32.of_string, F32.of_string)

  bendlang/bend#1789 · Filter by author adeerkhan opened on Oct 20, 2026
  1

• A do-block bind or let without its type annotation reports an unrelated error

  bendlang/bend#1787 · Filter by author HamedShams opened on Oct 20, 2026

• IO.model: a pure interpreter for laws about a program’s observable IO behavior

  bendlang/bend#1784 · Filter by author viridale opened on Oct 20, 2026

• Calling a def written below its caller reports "an unfilled law is a dead claim", not the ordering rule

  bendlang/bend#1782 · Filter by author viridale opened on Oct 20, 2026

• A tiled matmul in Bend runs about 4x slower than the same kernel handwritten in CUDA: where the time goes

  bendlang/bend#1781 · Filter by author nuxyel opened on Oct 20, 2026

• CUDA: the leaves of a balanced fork tree land on threads in an order that changes from run to run, so a layout cannot be coalesced

  bendlang/bend#1780 · Filter by author nuxyel opened on Oct 20, 2026

• The test and perf gates run ! on Metal only; CUDA-specific behaviour goes unnoticed

  bendlang/bend#1779 · Filter by author nuxyel opened on Oct 20, 2026

• CUDA: Array.new inside a bang fills the new block in one loop on one lane (~4.6 ns a cell)

  bendlang/bend#1778 · Filter by author nuxyel opened on Oct 20, 2026

• A safe way to give a fork tree's leaves disjoint parts of one Array to write (the counterpart of #1376)

  bendlang/bend#1777 · Filter by author nuxyel opened on Oct 19, 2026

• CUDA: the error poll in every flat loop (err_spun) makes ptxas yield on each iteration; tight loops run up to 20x slower

  bendlang/bend#1776 · Filter by author nuxyel opened on Oct 19, 2026

• Buffered Chan receives scale quadratically on the Node host

  bendlang/bend#1720 · Filter by author oxura opened on Oct 18, 2026

• C backend: a memory-bound loop's speed depends on unrelated code (flipping BLK_SHR in a program that never forks makes it 10-18% faster)

  bendlang/bend#1648 · Filter by author nuxyel opened on Oct 17, 2026

• Proposal for bend.ts: content-keyed template instance names, for parallel and cached checking

  bendlang/bend#1633 · Filter by author ScottMoore0 opened on Oct 17, 2026
  2

• Proposals for bend.ts: clearer messages for seven common mistakes

  bendlang/bend#1632 · Filter by author ScottMoore0 opened on Oct 17, 2026
  10

• err_fail's _exit and stdio leave an embedder no fatal path (terminal state, signals)

  bendlang/bend#1624 · Filter by author rofrol opened on Oct 16, 2026

• --verdict rejects a reused proof after reconstructing a constructor with a function field

  bendlang/bend#1623 · Filter by author sebastian-griego opened on Oct 16, 2026

• F32.from_nat wraps values at 2^32

  bendlang/bend#1609 · Filter by author oxura opened on Oct 16, 2026

• wasm32/Emscripten CPU-only build mode for generated C?

  bendlang/bend#1598 · Filter by author rofrol opened on Oct 16, 2026

• Freestanding C builds: a BEND_HOST hook that replaces the runtime's OS host

  enhancement
  bendlang/bend#1594 · Filter by author GunnarZarncke opened on Oct 15, 2026

• IO request to evaluate a pure function off the IO loop thread

  bendlang/bend#1575 · Filter by author rofrol opened on Oct 15, 2026

• A file read into an Array<U32>, so loading model weights is not one list cell per byte

  enhancement
  bendlang/bend#1573 · Filter by author nuxyel opened on Oct 15, 2026
  2

• One + on a List<&2, U32> seals every List cell a native build makes, List<&1, U32> ones included: a loop that shares nothing runs 2x slower

  bendlang/bend#1559 · Filter by author aldeni opened on Oct 14, 2026