# Dev **URL:** https://forum.graphviz.org/c/dev/8.md [Latest](https://forum.graphviz.org/latest.md) · [Categories](https://forum.graphviz.org/categories.md) --- ## [About the Dev category](https://forum.graphviz.org/t/about-the-dev-category/55)
**Author:** [@magjac](https://forum.graphviz.org/u/magjac)\ **Replies:** 0
Anything related to hacking on Graphviz: coding, submitting pull requests, configuring development environments, coding conventions, and so forth. Use this category for stuff that a normal Graphviz user wouldn’t care ab… --- ## [Bug report: Clustered subgraph leads to crash in dot](https://forum.graphviz.org/t/bug-report-clustered-subgraph-leads-to-crash-in-dot/3395)
**Author:** [@mmadsen\_cig](https://forum.graphviz.org/u/mmadsen_cig)\ **Replies:** 9\ **Last updated:** [September 16, 2026, 12:30pm UTC](https://forum.graphviz.org/t/bug-report-clustered-subgraph-leads-to-crash-in-dot/3395 "2026-09-16T12:30:12Z")
At my company, we use Graphviz to layout various graphs, including some data flow graphs to show how variables are being used across a number of scripts. We’ve noticed that in some scenarios, it will simply crash when i… --- ## [Latex labels for Graphviz (work in progress)](https://forum.graphviz.org/t/latex-labels-for-graphviz-work-in-progress/3402)
**Author:** [@HermannSW](https://forum.graphviz.org/u/HermannSW)\ **Replies:** 2\ **Last updated:** [September 7, 2026, 1:31am UTC](https://forum.graphviz.org/t/latex-labels-for-graphviz-work-in-progress/3402 "2026-09-07T01:31:21Z")
A year ago in Linear Algebra 1 lecture (I study Mathematics in my 60s) I created a big structure diagram with Graphviz. Now I wanted to create a similar structure diagram for Elementary number theory lecture, but hesita… --- ## [Using graphviz API directly to render graphs](https://forum.graphviz.org/t/using-graphviz-api-directly-to-render-graphs/2713)
**Author:** [@hos-b](https://forum.graphviz.org/u/hos-b)\ **Replies:** 1\ **Last updated:** [August 18, 2026, 1:24am UTC](https://forum.graphviz.org/t/using-graphviz-api-directly-to-render-graphs/2713 "2026-08-18T01:24:24Z")
Hi. I’m trying to use the gvrender\_engine\_t API to get the layout information performed using the dot layout algorithm. I have followed the official guide to write my own rendering plugin. Unfortunately I only noticed t… --- ## [dot-engine: a faithful pure-TypeScript port of Graphviz (no WASM) — plus markdown/SSG plugins and a VS Code extension](https://forum.graphviz.org/t/dot-engine-a-faithful-pure-typescript-port-of-graphviz-no-wasm-plus-markdown-ssg-plugins-and-a-vs-code-extension/3388)
**Author:** [@sseely](https://forum.graphviz.org/u/sseely)\ **Replies:** 1\ **Last updated:** [August 1, 2026, 11:43am UTC](https://forum.graphviz.org/t/dot-engine-a-faithful-pure-typescript-port-of-graphviz-no-wasm-plus-markdown-ssg-plugins-and-a-vs-code-extension/3388 "2026-08-01T11:43:45Z")
Hi all — I’d like to share a project some of you may find interesting (or alarming): a faithful port of Graphviz from the C source to pure TypeScript. Engine — @knowvah/dot-engine (npm: @knowvah/dot-engine, EPL-2.0 like… --- ## [New Installer Package for macOS](https://forum.graphviz.org/t/new-installer-package-for-macos/1812)
**Author:** [@zosmac](https://forum.graphviz.org/u/zosmac)\ **Replies:** 22\ **Last updated:** [June 3, 2026, 11:38am UTC](https://forum.graphviz.org/t/new-installer-package-for-macos/1812 "2026-06-03T11:38:43Z")
I have coded a makefile and updated a few of the source and build files of Graphviz to build a macOS installer package. This package installs graphviz dot and plugins into /usr/local/graphviz, adds /usr/local/graphviz/bi… --- ## [\#include "config.h" in .h files](https://forum.graphviz.org/t/include-config-h-in-h-files/3327)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 2\ **Last updated:** [April 25, 2026, 5:49am UTC](https://forum.graphviz.org/t/include-config-h-in-h-files/3327 "2026-04-25T05:49:00Z")
I was writing a new C test to run from test\_c\_utils.py and I found that #include “config.h” is a problem for such tests, as we don’t know for sure where the config file is when the test is run. I see several solutions: … --- ## [Test cases in the codebase](https://forum.graphviz.org/t/test-cases-in-the-codebase/3301)
**Author:** [@steveroush](https://forum.graphviz.org/u/steveroush)\ **Replies:** 6\ **Last updated:** [April 17, 2026, 10:09pm UTC](https://forum.graphviz.org/t/test-cases-in-the-codebase/3301 "2026-04-17T22:09:32Z")
\[no guarantees that the following is 100% accurate, but it is pretty close\] Good news: There are 822 unique \*.dot and \*.gv files in the codebase There are 822 unique \*.dot and \*.gv files in the codebase There are 717 u… --- ## [Graphviz + Nix... Any interest?](https://forum.graphviz.org/t/graphviz-nix-any-interest/3326)
**Author:** [@caffeine\_storm](https://forum.graphviz.org/u/caffeine_storm)\ **Replies:** 1\ **Last updated:** [April 9, 2026, 11:58pm UTC](https://forum.graphviz.org/t/graphviz-nix-any-interest/3326 "2026-04-09T23:58:03Z")
Hi all, Recently, in orthogonal efforts, I’ve been trying to pick up Nix and seeing if I can hack on Graphviz (r.e. vt100 output format). On a lark, I decided to smush these efforts together :upside\_down\_face: . I’ve g… --- ## [Public API and headers again](https://forum.graphviz.org/t/public-api-and-headers-again/3324)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 5\ **Last updated:** [April 2, 2026, 6:20am UTC](https://forum.graphviz.org/t/public-api-and-headers-again/3324 "2026-04-02T06:20:48Z")
I see this general issue has been discussed in the past, but I just stumbled across a new question: is there an existing internal include file where stuff from types.h should be moved if it’s not appropriate for public A… --- ## [Graphviz archaeology](https://forum.graphviz.org/t/graphviz-archaeology/3323)
**Author:** [@steveroush](https://forum.graphviz.org/u/steveroush)\ **Replies:** 1\ **Last updated:** [March 21, 2026, 12:09pm UTC](https://forum.graphviz.org/t/graphviz-archaeology/3323 "2026-03-21T12:09:37Z")
Here are some ancient Graphviz links: old github repo (emden) https://emden.github.io/ old github repo (ellison) GitHub - ellson/MOTHBALLED-graphviz: Moved to https://gitlab.com/graphviz/graphviz · GitHub Internet Arc… --- ## [Development scripts/tips location?](https://forum.graphviz.org/t/development-scripts-tips-location/3320)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 11\ **Last updated:** [March 11, 2026, 7:36pm UTC](https://forum.graphviz.org/t/development-scripts-tips-location/3320 "2026-03-11T19:36:42Z")
I’ve been debugging Issue 1213 and friends. I’ve apparently fixed the immediate issue but have some funky intermediate output. I incrementally worked with Claude to whip up some instrumentation output (gated by DEBU… --- ## [GVBINDIR and ctest](https://forum.graphviz.org/t/gvbindir-and-ctest/3317)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 1\ **Last updated:** [March 5, 2026, 9:48pm UTC](https://forum.graphviz.org/t/gvbindir-and-ctest/3317 "2026-03-05T21:48:50Z")
I’ve noticed that environment variable GVBINDIR is used to tell ctest where to find plugins, but is not documented anywhere. I found a forum thread suggesting that this was a solution to a problem finding plugins on Ma… --- ## [Windows plugins?](https://forum.graphviz.org/t/windows-plugins/3309)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 2\ **Last updated:** [February 24, 2026, 6:05pm UTC](https://forum.graphviz.org/t/windows-plugins/3309 "2026-02-24T18:05:21Z")
Now that I’ve found problems with MinGW, I’m wondering if plugins are working on other Windows builds. In particular, the MinGW .dll files are being placed far away from the index file pkgIndex.tcl so when I run manuall… --- ## [Random Number Generation](https://forum.graphviz.org/t/random-number-generation/3303)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 5\ **Last updated:** [February 22, 2026, 8:19pm UTC](https://forum.graphviz.org/t/random-number-generation/3303 "2026-02-22T20:19:07Z")
I previously raised this issue in an issue, but I think that isn’t the best forum for discussion, so let’s discuss the rand issue here instead. To summarize that issue: I asked Gemini to look at matrix\_ops.c and suggest… --- ## [Font specification? "Times New Roman"](https://forum.graphviz.org/t/font-specification-times-new-roman/3255)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 9\ **Last updated:** [February 22, 2026, 6:15am UTC](https://forum.graphviz.org/t/font-specification-times-new-roman/3255 "2026-02-22T06:15:32Z")
I recently have a bit of time and was thinking of trying to help improve graphviz performance, since it’s a tool I seem to use often in my work, and it hasn’t speeded up as much as computer hardware has over the past few… --- ## [Replicating Linux CI tests locally](https://forum.graphviz.org/t/replicating-linux-ci-tests-locally/3302)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 3\ **Last updated:** [February 20, 2026, 4:59pm UTC](https://forum.graphviz.org/t/replicating-linux-ci-tests-locally/3302 "2026-02-20T16:59:31Z")
I was studying the GiitLab CI process a bit and found that it is pretty easy to run the Linux CI tests locally on a dev machine (probably even a non-Linux one, as long as the processor matches) using gitlab-ci-local and … --- ## [Issues Encountered While Testing Example Code in libguide.pdf](https://forum.graphviz.org/t/issues-encountered-while-testing-example-code-in-libguide-pdf/3300)
**Author:** [@The\_book](https://forum.graphviz.org/u/The_book)\ **Replies:** 2\ **Last updated:** [February 12, 2026, 3:46pm UTC](https://forum.graphviz.org/t/issues-encountered-while-testing-example-code-in-libguide-pdf/3300 "2026-02-12T15:46:54Z")
Copying directly from the pdf is inconvenient. demo.c:13:5: error: too few arguments to function ‘agopen’ g = agopen(“g”, Agdirected); There are two parameters for agopen in the pdf, but it needs to be supplemented to… --- ## [Large GraphViz test cases? Parallelization and tuning](https://forum.graphviz.org/t/large-graphviz-test-cases-parallelization-and-tuning/3257)
**Author:** [@brianrmurphy](https://forum.graphviz.org/u/brianrmurphy)\ **Replies:** 16\ **Last updated:** [February 10, 2026, 9:23pm UTC](https://forum.graphviz.org/t/large-graphviz-test-cases-parallelization-and-tuning/3257 "2026-02-10T21:23:18Z")
I’ve found some mention of a few large test case files bevy.gv and ftzz.gv, but I cannot find these files anywhere. Where might they be? I have my own test case I stumbled upon, but it’s apparently way too big to allow… --- ## [A speed-up trick for dot performance testing](https://forum.graphviz.org/t/a-speed-up-trick-for-dot-performance-testing/3298)
**Author:** [@steveroush](https://forum.graphviz.org/u/steveroush)\ **Replies:** 0\ **Last updated:** [February 10, 2026, 5:18am UTC](https://forum.graphviz.org/t/a-speed-up-trick-for-dot-performance-testing/3298 "2026-02-10T05:18:25Z")
If you are testing dot with large, slow input files using some combination of nslimit mclimit remincross searchsize to speed up the test and make it tolerable (e.g. dot 2854\_0.gv -Tsvg -v -Gnslimit=2 -Gmclimit=.22 -Gr… --- ## [GraphViz DLLs on Windows](https://forum.graphviz.org/t/graphviz-dlls-on-windows/3241)
**Author:** [@Robert\_Hairgrove](https://forum.graphviz.org/u/Robert_Hairgrove)\ **Replies:** 15\ **Last updated:** [November 20, 2025, 10:20am UTC](https://forum.graphviz.org/t/graphviz-dlls-on-windows/3241 "2025-11-20T10:20:51Z")
Which GraphViz DLLs on Windows do I need to include in an installer for an app of mine which uses GraphViz as a dependency? Most of all, I just need the core engines and renderers, but there are many things of late such … --- ## [Gvedit: library 'util\_C' not found](https://forum.graphviz.org/t/gvedit-library-util-c-not-found/3231)
**Author:** [@dallured](https://forum.graphviz.org/u/dallured)\ **Replies:** 14\ **Last updated:** [November 8, 2025, 9:40pm UTC](https://forum.graphviz.org/t/gvedit-library-util-c-not-found/3231 "2025-11-08T21:40:46Z")
I am doing maintenance for Graphviz on MacPorts, trying to update from version 12, to current version 14.0.2. Part of the build is in effect, a stand-alone Autotools build of gvedit. This error hits when linking the exe… --- ## [Memory leak caused by agwrite](https://forum.graphviz.org/t/memory-leak-caused-by-agwrite/3210)
**Author:** [@aleqsonder](https://forum.graphviz.org/u/aleqsonder)\ **Replies:** 12\ **Last updated:** [October 8, 2025, 11:46am UTC](https://forum.graphviz.org/t/memory-leak-caused-by-agwrite/3210 "2025-10-08T11:46:58Z")
Hello! I was implementing a C-function converting abstract syntax tree to Agraph\_t \* to output it then in the DOT format. I called the agwrite function to print the converted tree out as a graph and used the agclose to… --- ## [Problem running autogen.sh on macOS](https://forum.graphviz.org/t/problem-running-autogen-sh-on-macos/3192)
**Author:** [@Robert\_Hairgrove](https://forum.graphviz.org/u/Robert_Hairgrove)\ **Replies:** 11\ **Last updated:** [October 4, 2025, 3:45pm UTC](https://forum.graphviz.org/t/problem-running-autogen-sh-on-macos/3192 "2025-10-04T15:45:59Z")
I have cloned the latest code from GitLab to my MacBook Air running Sequoia version 15.7. Running ./autogen.sh exits with the errors shown at the end of the output: configure.ac:213: the top level configure.ac:185: erro… --- ## [Cannot use Graphviz as lib on windows with C++](https://forum.graphviz.org/t/cannot-use-graphviz-as-lib-on-windows-with-c/1960)
**Author:** [@SadE](https://forum.graphviz.org/u/SadE)\ **Replies:** 2\ **Last updated:** [October 3, 2025, 2:30pm UTC](https://forum.graphviz.org/t/cannot-use-graphviz-as-lib-on-windows-with-c/1960 "2025-10-03T14:30:35Z")
Hi, I’m trying to setup a usable graphviz lib setup on VS 2022. I added all the 35 lib provided in the windows zip, the header files. I can compile a little basic example, but at the linking i got this error : |Error|L… --- ## [Bug with latest release (v14.0.0)?](https://forum.graphviz.org/t/bug-with-latest-release-v14-0-0/3208)
**Author:** [@brettc](https://forum.graphviz.org/u/brettc)\ **Replies:** 3\ **Last updated:** [October 3, 2025, 9:21am UTC](https://forum.graphviz.org/t/bug-with-latest-release-v14-0-0/3208 "2025-10-03T09:21:44Z")
I just upgraded to v14 via brew and my dot images are broken. \[dot\] digraph { graph \[bgcolor=transparent dpi=180 nodesep=0.2 pad=0.1 rankdir=TB ranksep=0.2\] node \[color=“#4361ee” fillcolor=transparent fixedsize=None … --- ## [Configure script looking for \`pangoft2\` library on macOS](https://forum.graphviz.org/t/configure-script-looking-for-pangoft2-library-on-macos/3191)
**Author:** [@Robert\_Hairgrove](https://forum.graphviz.org/u/Robert_Hairgrove)\ **Replies:** 2\ **Last updated:** [September 20, 2025, 7:59am UTC](https://forum.graphviz.org/t/configure-script-looking-for-pangoft2-library-on-macos/3191 "2025-09-20T07:59:32Z")
Trying to build Graphviz 13.2 on macOS. If I’m not mistaken, pangocairo is built with the quartz backend on macOS and does not use freetype on that platform. I actually built and installed libfreetype2 on this system, b… --- ## [Licence for libANN is GPL and not LGPL?](https://forum.graphviz.org/t/licence-for-libann-is-gpl-and-not-lgpl/3188)
**Author:** [@Robert\_Hairgrove](https://forum.graphviz.org/u/Robert_Hairgrove)\ **Replies:** 15\ **Last updated:** [September 19, 2025, 12:59am UTC](https://forum.graphviz.org/t/licence-for-libann-is-gpl-and-not-lgpl/3188 "2025-09-19T00:59:59Z")
I have been looking for ways of building GraphViz from sources on my new MacBook Air without using Homebrew or MacPorts, if possible. We use the GraphViz libraries in another project built with the Qt frameworks. It has … --- ## [Why didn't change \`CDT\_VERSION\`](https://forum.graphviz.org/t/why-didnt-change-cdt-version/3166)
**Author:** [@FeelUs](https://forum.graphviz.org/u/FeelUs)\ **Replies:** 5\ **Last updated:** [September 9, 2025, 12:14am UTC](https://forum.graphviz.org/t/why-didnt-change-cdt-version/3166 "2025-09-09T00:14:06Z")
I look at history of libcdt API: https://gitlab.com/graphviz/graphviz/-/blob/8.1.0/lib/cdt/cdt.h?ref\_type=tags#L87 https://gitlab.com/graphviz/graphviz/-/blob/9.0.0/lib/cdt/cdt.h?ref\_type=tags#L89 https://gitlab.com/g… --- ## [Default value for agattr(g,AGNODE,"name",NULL)](https://forum.graphviz.org/t/default-value-for-agattr-g-agnode-name-null/3180)
**Author:** [@FeelUs](https://forum.graphviz.org/u/FeelUs)\ **Replies:** 6\ **Last updated:** [September 6, 2025, 1:38pm UTC](https://forum.graphviz.org/t/default-value-for-agattr-g-agnode-name-null/3180 "2025-09-06T13:38:10Z")
How does agattr/agattr\_text(g,AGNODE,"name",NULL) behave if the nodes of the graph do not have the “name” attribute? If some nodes of the graph have the “name” attribute, what will be the default value for nodes withou… [Next page](https://forum.graphviz.org/c/dev/8.md?page=1)