08 Sep 2026

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Firefox Nightly: Motion, Colour, Captions, Kit – These Weeks in Firefox: Issue 207

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08 Sep 2026 6:38pm GMT

07 Sep 2026

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The Rust Programming Language Blog: Rust debugging survey 2026 results

One of the biggest challenges Rust developers report in our annual surveys is a subpar debugging experience. So, back in February, we ran our first Rust Debugging Survey, in the hopes of identifying how Rust developers are using debuggers and what problems they are facing when doing so. We received over 2,300 responses, and we'd like to thank everyone who took the time to participate in the survey!

In this report, we'll go over some of the results of the survey. If you'd like, you can also check out the complete results of the survey.

If you'd like to skip ahead to any particular section, you can do so with this index:

Who Uses Debuggers?

The first step to making sense of the survey results is understanding who took the survey. We asked respondents to rate their Rust expertise, from "Never used it" to "Advanced". Over 80% reported themselves as "Advanced" or "Intermediate", split roughly evenly between the two:

<noscript> <img alt="how-would-you-rate-your-rust-expertise" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/how-would-you-rate-your-rust-expertise.png" /> </noscript>
[PNG] [SVG]

We also asked respondents if they currently use or have used debuggers in Rust. Over 46% said they currently do, with the remaining responses split between "have in the past" and "never have". That means that over half of respondents do not currently use a debugger for Rust!

<noscript> <img alt="do-you-use-debuggers-in-rust" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/do-you-use-debuggers-in-rust.png" /> </noscript>
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Categorized by expertise, the responses reveal that roughly half of "beginners" have never used debuggers in Rust! On the other hand, nearly half of "advanced users" currently do use debuggers in Rust:

<noscript> <img alt="do-you-use-debuggers-in-rust-per-expertise" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/do-you-use-debuggers-in-rust-per-expertise.png" /> </noscript>
[PNG] [SVG]

For respondents who indicated they had previously used Rust but no longer did, we asked if challenges with debugging support were why they stopped. For nearly 3%, the answer was "yes", with an additional 24% reporting debugging issues as being partially responsible (though mind the small response count; most respondents were active users of Rust):

<noscript> <img alt="were-issues-with-debugging-support-the-primary-reason-why-you-stopped-using-rust" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/were-issues-with-debugging-support-the-primary-reason-why-you-stopped-using-rust.png" /> </noscript>
[PNG] [SVG]

How Are Debuggers Used?

Knowing what debuggers developers are using and how is another important part of understanding the challenges they face. To this end, we asked respondents how they were debugging their programs. Unsurprisingly, most developers make use of print debugging and the dbg! macro. Excluding those, using lldb inside an IDE was the most popular choice, followed by gdb on the command line:

<noscript> <img alt="what-tools-and-workflows-do-you-use-to-debug-rust-programs" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/what-tools-and-workflows-do-you-use-to-debug-rust-programs.png" /> </noscript>
[PNG] [SVG]

We can get a more detailed breakdown of these results if we include the operating system on which the respondents use a given debugging approach. We examine this from two different angles. The first angle being, "On operating system X, what percent of responses are using debugger Y?". Print debugging and the dbg! macro are consistently the top two yet again, but looking beyond that, things get more interesting. On Linux, using gdb on the command line was the most popular choice by a thin margin, beating lldb in an IDE by only 0.4%. On Windows, Windows Subsystem for Linux (WSL), and macOS, lldb in an IDE was the top pick by at least 6%, making it a very popular choice in general. On Windows, the three least popular choices were the command line debuggers (gdb CLI, lldb CLI, and BugStalker), and on both Windows and macOS the third most popular pick was, "I don't know". Those who were debugging on operating systems not listed (Other) most frequently used some kind of special embedded debugger or gdb:

<noscript> <img alt="what-tools-and-workflows-do-you-use-to-debug-rust-programs-per-os-1" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/what-tools-and-workflows-do-you-use-to-debug-rust-programs-per-os-1.png" /> </noscript>
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The other angle we can look at these responses from is, "For users of debugger X, what percent of responses are using it on operating system Y?". For most debuggers, Linux makes up the largest portion of uses, ranging from about 45% to about 77%, followed by Windows, then macOS. The most notable exceptions are WinDbg and the Visual Studio debugger, which are primarily used on Windows, and lldb, which is used more on macOS than Windows in an IDE and on the command line:

<noscript> <img alt="what-tools-and-workflows-do-you-use-to-debug-rust-programs-per-os-2" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/what-tools-and-workflows-do-you-use-to-debug-rust-programs-per-os-2.png" /> </noscript>
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To the 6 respondents who use WinDbg on Linux: we wish you luck!

As for how people actually use their debugger of choice, the aggregate results are not particularly surprising. Roughly 87% of users are using debuggers for stepping line-by-line through programs and a little over half of users are using debuggers to obtain stack traces from hung/crashed processes. Only a quarter of the respondents use a debugger to debug async code. That might be partially caused by the async Rust debugging experience being clumsy and incomplete, or it could just be that users aren't writing much async code:

<noscript> <img alt="what-are-you-using-debuggers-for" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/what-are-you-using-debuggers-for.png" /> </noscript>
[PNG] [SVG] [Wordcloud of open answers]

If we break these results down by expertise, we can learn a bit more about usage patterns. As users become more experienced with Rust, their use of debuggers for learning purposes decreases, and they get more stack traces from crashed processes:

<noscript> <img alt="what-are-you-using-debuggers-for-per-expertise" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/what-are-you-using-debuggers-for-per-expertise.png" /> </noscript>
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The final bit of insight into how Rustaceans use debuggers is if they are debugging programs that use Rust alongside other programming languages. For 44% of respondents, the answer is "yes", which is a pretty high number!

As for which languages those are, C dominates the scene at a little over 70%, followed by C++ at about 43% and Python at about 20%:

<noscript> <img alt="do-you-debug-programs-that-combine-rust-with-any-of-the-following-languages" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/do-you-debug-programs-that-combine-rust-with-any-of-the-following-languages.png" /> </noscript>
[PNG] [SVG] [Wordcloud of open answers]

Challenges

Instead of diving right into asking, "what problems do you face when using debuggers?", or something to that effect, we first asked respondents why they decide against using debuggers whenever they do, including for reasons that aren't necessarily "problems with debuggers".

The most commonly reported reason was that it was easier or faster to use logs or print debugging to solve problems, reported by a little over 81% of respondents. This could partially be explained by the open responses, which featured complaints that debuggers were too difficult to set up and/or use (especially on Windows, when dealing with Web Assembly, or in embedded contexts) and sentiment suggesting that small and/or simple problems just don't really need a debugger. It does leave one wondering if the user experience could be made convenient enough to dethrone print debugging, but it seems hard to beat something so intuitive. This is followed by roughly 37% of respondents who write code that Just Works. Fair enough. After that, about 26% of respondents indicated that they've decided not to use debuggers in situations where the language features they were working with had poor support. This is slightly more than issues with standard library types, at about 22%, which is slightly more than issues with external library types, at about 20%:

<noscript> <img alt="when-you-dont-use-a-debugger-why-dont-you" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/when-you-dont-use-a-debugger-why-dont-you.png" /> </noscript>
[PNG] [SVG] [Wordcloud of open answers]

As stepping through code was anticipated to be one of the most common uses for debuggers, we directly asked respondents if they faced any issues when doing so. A little over 51% of respondents said they did! Of those who reported that they experienced issues stepping through code, we asked when they were experiencing issues. Async code was the most common case reported at slightly over 28%, followed by code involving macros at about 23%. The least common case reported was code involving function pointers, at almost 6%:

<noscript> <img alt="when-do-you-experience-issues-with-trying-to-step-through-code-with-your-debugger" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/when-do-you-experience-issues-with-trying-to-step-through-code-with-your-debugger.png" /> </noscript>
[PNG] [SVG] [Wordcloud of open answers]

We also directly asked respondents which types in the standard library were hard to work with, if any. This was an open-response question, and reading through the responses, some particularly common complaints were with enums and collections, particularly std::collections::HashMap and std::vec::Vec. This is also visible in the word cloud in the full report.

We asked respondents to indicate which pain points, if any, they have encountered when using debuggers with Rust. At slightly over 74%, poor representation of values was the most common pain point by a decent margin, followed by being unable to print variables at just over 55%:

<noscript> <img alt="which-of-these-pain-points-have-you-experienced-using-a-debugger-with-rust" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/which-of-these-pain-points-have-you-experienced-using-a-debugger-with-rust.png" /> </noscript>
[PNG] [SVG]

Debugger Visualizers

We asked respondents to indicate if they were library authors, and if so, if they were aware of and using the debugger_visualizer attribute. Nearly 62% of respondents indicated that they were library authors who were not aware of this attribute:

<noscript> <img alt="if-you-are-a-library-author-are-you-aware-of-and-using-the-debugger-visualizer-attribute" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/if-you-are-a-library-author-are-you-aware-of-and-using-the-debugger-visualizer-attribute.png" /> </noscript>
[PNG] [SVG]

For those who indicated that they were library authors who knew about the attribute but did not use it, we also asked why. This represented a much smaller fraction of respondents, so keep that in mind! That said, half of these library authors indicated that they didn't have the time to maintain visualizer attributes, and just under half indicated they didn't know how to write visualizer scripts:

<noscript> <img alt="why-dont-you-use-the-debugger-visualizer-attribute" src="https://blog.rust-lang.org/2026/09/07/rust-debugging-survey-2026-results/why-dont-you-use-the-debugger-visualizer-attribute.png" /> </noscript>
[PNG] [SVG] [Wordcloud of open answers]

For those of you who have been reading this section asking yourself what the debugger_visualizer attribute is, you can read up on it in The Rust Reference: Debugger Attributes. The quick explanation is that the debugger_visualizer attribute can be applied to modules or the crate root to embed files in the debug information which improve the display of values with certain debuggers. The two currently supported file types are Natvis files, used by Microsoft debuggers such as WinDbg, and GDB "pretty printers", which are structured Python scripts used by GDB.

Closing Remarks

Thanks to your participation in this survey, we've gained some great insights about how Rustaceans are using debuggers and what issues they are facing. For example, knowing that such a high number of users are dealing with poor representation of values pairs well with knowing which standard library types are causing issues, knowing that many library authors haven't heard of the debugger_visualizer attribute, and knowing that many of those who have but don't use it either don't know how or don't have time to maintain visualizer scripts.

Looking to the future, the survey results have suggested that there are a few notable ways we could most significantly improve the debugging experience in Rust, such as:

A common suggestion that could resolve those first three points is to use the Debug implementation of types to display them in debuggers. There are challenges to that approach, such as the fact that the Debug implementation is not present in the final binary unless it is actually used somewhere in the program, but it isn't impossible. Notably, this is already supported by the BugStalker debugger (given the same condition that the Debug implementation must actually be used), which some of you first heard about from the survey! It also appears to have some support for async, with plans to expand.

One notable way the debugger experience is currently being improved is through the ongoing Google Summer of Code project improving how we test debug info and visualizer scripts, making it easier to maintain and improve our own visualizer scripts and general compatibility with visualizer scripts without silent breakage or regressions.

Once again, we'd like to thank everyone who took the time to participate in the survey!

07 Sep 2026 12:00am GMT

04 Sep 2026

feedPlanet Mozilla

Firefox Tooling Announcements: Firefox DevTools MCP 0.10.2 released

Firefox DevTools MCP (firefox-devtools-mcp) 0.10.2 is out on npm.

New tools:

Other changes:

Install:

claude mcp add firefox-devtools npx @mozilla/firefox-devtools-mcp@latest

codex mcp add firefox-devtools - npx @mozilla/firefox-devtools-mcp@latest

For internal Firefox development, swap firefox-devtools-mcp with firefox-devtools-mcp-moz in order to benefit from additional tools, such as chrome-privileged script execution.

Special thanks to all the contributors who filed issues and submitted patches for this release: freema, f3tch (github), jasonanovak and shoemoney.

Full changelog: https://github.com/mozilla/firefox-devtools-mcp/releases/tag/v0.10.2
Repository and issues: GitHub - mozilla/firefox-devtools-mcp: Model Context Protocol server for Firefox DevTools - enables AI assistants to inspect and control Firefox browser through the Remote Debugging Protocol · GitHub
Public chatroom: https://chat.mozilla.org/#/room/#firefox-devtools-mcp:mozilla.org

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04 Sep 2026 1:41pm GMT