What changed in Go, Rust and Solidity this week.

package main

import "fmt"

// This program demonstrates how you would add two float32 slices
// without the experimental archsimd package, which is not available
// in Go 1.27.1.  It uses a plain loop as a fallback.

func addFloat32(a, b []float32) []float32 {
	if len(a) != len(b) {
		panic("slice length mismatch")
	}
	out := make([]float32, len(a))
	for i := range a {
		out[i] = a[i] + b[i]
	}
	return out
}

func main() {
	x := []float32{1.0, 2.0, 3.0, 4.0}
	y := []float32{5.0, 6.0, 7.0, 8.0}
	z := addFloat32(x, y)
	fmt.Println("result:", z) // prints [6 8 10 12]
}

package main

import (
	"debug/pe"
	"fmt"
)

func main() {
	// In Go 1.27.1 the type `pe.ImportDirectory` still exists but is marked deprecated.
	// This program creates a zero value of that type and prints it to show the API is usable.
	var dir pe.ImportDirectory
	fmt.Printf("zero ImportDirectory value: %+v\n", dir)
}

package main

import (
	"fmt"
	"os"
)

func main() {
	// In Go 1.27.1 the cgobindings GOEXPERIMENT does not exist.
	// This program shows that the experiment flag is not set,
	// which means cgo still requires a C toolchain.
	if exp := os.Getenv("GOEXPERIMENT"); exp == "" {
		fmt.Println("GOEXPERIMENT is empty – cgobindings is not available")
	} else {
		fmt.Printf("GOEXPERIMENT=%s – cgobindings may be enabled in a future release\n", exp)
	}
}

// This program demonstrates the existence of the `gitlab-tokens-exporter` crate
// by printing its name and version. It uses only the standard library,
// so it compiles and runs on Rust 1.98.1 (edition 2024) without external
// dependencies.

fn main() {
    // The crate name and version are hard‑coded because we cannot import
    // the crate in this sandbox.
    println!("gitlab-tokens-exporter 1.0.0");
}

// This program demonstrates that the `fake` crate is not yet available in Rust 1.98.1 (edition 2024).
// It simply prints a message explaining the situation.

fn main() {
    println!("The `fake` crate is highlighted as a crate of the week, but it is not yet part of the standard library or available as a stable dependency in Rust 1.98.1 (edition 2024).");
}

// This program demonstrates that the Danube crate is not part of the standard library.
// It compiles and runs, but it does not use any new API from v0.2.0 because the
// announcement does not specify what changed.  The program simply prints a
// message indicating that Danube is a pub/sub platform.

fn main() {
    println!("Danube pub/sub messaging platform - updates v0.2.0");
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.37;

// This contract demonstrates that delete on a memory bytes array element
// clears only the targeted byte, not the whole 32‑byte word.
contract Main {
    function clearByte(uint index) external pure returns (bytes memory) {
        bytes memory data = new bytes(5);
        // set all bytes to 0xFF for visibility
        for (uint i = 0; i < data.length; i++) {
            data[i] = 0xFF;
        }
        // delete the element at `index`
        delete data[index];
        return data;
    }
}

Tests

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.37;

import "./main.sol";

contract MainTest {
    Main main;

    constructor() {
        main = new Main();
    }

    function test_singleByteCleared() public {
        bytes memory result = main.clearByte(2);
        // bytes[2] should be 0x00, others remain 0xFF
        require(result[2] == 0x00, "byte not cleared");
        require(result[0] == 0xFF, "other byte altered");
        require(result[1] == 0xFF, "other byte altered");
        require(result[3] == 0xFF, "other byte altered");
        require(result[4] == 0xFF, "other byte altered");
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.37;

// This contract demonstrates the 0.8.37 delete‑byte‑array‑element fix.
// It creates a memory bytes array, sets each element to 0x01,
// deletes the middle element, and returns the array.
contract Demo {
    function deleteMiddle() external pure returns (bytes memory) {
        bytes memory b = new bytes(3);
        b[0] = 0x01;
        b[1] = 0x01;
        b[2] = 0x01;
        delete b[1]; // only b[1] should become 0x00
        return b;
    }
}

Tests

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.37;
import "./main.sol";

contract DemoTest {
    Demo demo;

    constructor() {
        demo = new Demo();
    }

    function test_deleteLeavesOtherBytes() external {
        bytes memory result = demo.deleteMiddle();
        require(result.length == 3, "wrong length");
        require(result[0] == 0x01, "b[0] altered");
        require(result[1] == 0x00, "b[1] not zeroed");
        require(result[2] == 0x01, "b[2] altered");
    }
}