Top developer communities by technology: the 2026 directory

If you run developer marketing for a Rust tool, you need to know where Rust engineers talk, not where developers in general talk. Every existing list of developer communities answers the general question: Stack Overflow, Reddit, Hacker News, Slack, and Discord. That tells you nothing about where to reach the people who use what you build.

We built this directory the other way round: technology first, then the communities that serve it, with a note on what each room is for and who is in it.

The research surfaced something we did not expect. Almost every technology has separate rooms for people using it and for people building it, and the two are rarely the same size or culture. Rust's most widely linked Discord server is a read-only archive. Kubernetes Slack prohibits posting your blog. The iOS Developers Slack will not let you in without a member vouching for you. That kind of thing does not appear in a list of links, and it is the difference between a distribution plan that works and one that gets you muted.

How to use this directory

Jump to your technology using the section headers. Each entry includes the community name, the platform it runs on, a member count when available, a verified link, and a short description of what happens there.

Where a community spans several technologies, we list it once in its primary section and cross-reference it elsewhere. CNCF Slack sits under cloud native, though it also includes channels for observability, service mesh, securty and runtime.

A word for DevRel and developer advocates

Most of you found this page because you need distribution. We want to be careful about that, because these rooms have good reason to be suspicious of you.

The Kubernetes Slack guidelines are worth quoting. Posting about your blog, podcast, or project to drive traffic falls under prohibited activities, in the same section as spam, and can result in a warning, a posting restriction, or a deactivated account. Job posts belong in one channel and pass through a moderated queue. This is not unusual. It is what a community does after enough people have treated it as a billboard.

The useful move is slower and works better. Answer questions in your area of expertise for a few weeks before you post anything of your own. Form an opinion and defend it. When someone hits the exact problem your product solves, you will have earned the standing to say so, and it will land as help rather than as an ad.

Treat each community below as a place to be a developer; the distribution follows. Treat it as a channel, and you will burn it.

How we chose these communities

Every link here was opened and confirmed live. Discord and Slack entries were checked on 13 July 2026, Reddit entries on 18 July 2026.

Member counts came from the platforms themselves. That rule cost us more entries than any other, because published counts are wrong almost everywhere. Hugging Face's Discord is described as having 18,000, 33,000, 50,000, 90,000, and 100,000 members across live pages, including Hugging Face's own documentation. The figure on the invite endpoint is 226,276. The Kubernetes contributor site gives two different numbers on the same page.

Reddit reports two different things depending on the subreddit, and we have labeled which is which rather than presenting them as one number. Some show subscribers or members. Others show weekly visitors, which is traffic rather than membership. Weekly contribution counts are quoted where Reddit displays them because, for a directory like this one, how much gets posted matters more than how many people once clicked "join".

Slack workspaces mostly publish nothing. Where a community states its own size, we have noted it and marked it as self-reported.

We removed communities where the last public activity was more than 90 days before our verification date. We listed one dead community deliberately, Rust's archived Discord, because it still ranks and still misleads people.

Rust

Rust is the clearest example of why platform-level lists fail. The server most people link to has been dead for years.

The Rust Programming Language (archive)- 53K members - read-only - https://users.rust-lang.org/t/rust-discord-server/136703

Listed as a warning. The server description says it is not used anymore, and Rust Forge confirms it was shut down in favor of Zulip. It still holds 53,010 members and still ranks in search. Directories that do not verify their links send people here.

Rust Programming Language Community - Discord - 70K members - discord.gg/rust-lang-community

The largest live Rust chat, run by the community rather than the project. General channels for questions, plus deeper ones for compiler development, web development, and GUI work. Casual conversation and day-to-day help happen here.

Rust Users Forum - Discourse - users.rust-lang.org

The official venue for usage questions. Slower than chat, searchable, and answers persist. If you are writing content for Rust developers, read it to learn what they are stuck on.

Rust Zulip - Zulip - rust-lang.zulipchat.com

Where the language gets built. Compiler, language, library, and infrastructure teams coordinate here. Do not bring usage questions, and do not bring your tutorial. The maintainers opened an issue on the rust-lang website asking for the community page to be reorganized, because people kept arriving from it with questions that belonged on the forum.

r/rust - Reddit - 165K members, 4.5K weekly contributions - reddit.com/r/rust

Crate announcements, release threads, and new projects. The moderators run standing megathreads that shape how the room works, including a weekly question thread, a weekly "what are you working on" thread, and an official hiring thread tied to each Rust release. Posting a project here is normal. Posting a question outside the megathread is less welcome.

Python

Python's split runs between a very large teaching community and a small room where the language itself is decided.

Python Discord - Discord - 427K members - discord.gg/python

The largest programming community on Discord and one of the largest anywhere. Python.org lists it on the official community page. More than a hundred volunteer helpers staff the help channels across all time zones, and the server hosts code jams and open-source events. Heavily weighted toward learners, which makes it excellent for education content and poor for anything aimed at senior engineers.

Python Discourse - Discourse - discuss.python.org

Where CPython gets decided. PEP discussion, core development, and release management. When the free-threaded Python contributors needed a place for user questions, they opened a separate Discord rather than fielding them here, which tells you how the room sees its purpose.

r/Python - Reddit - 114K members - reddit.com/r/Python

News, packages, and project announcements. The sidebar routes beginners elsewhere, which keeps the front page weighted toward working engineers. Daily threads carry the recurring traffic, including a Saturday resource-sharing thread and a Thursday careers thread.

r/learnpython - Reddit - 248K weekly visitors, 1.6K weekly contributions - reddit.com/r/learnpython

Where r/Python sends its beginners. An Ask Anything Monday thread anchors the week. The audience is people mid-course rather than mid-career, which makes it the right room for teaching material and the wrong one for anything aimed at senior engineers.

Go

Go documents its own split more clearly than most. The go.dev help page routes you to a different place depending on what you want.

Gophers Slack - Slack - invite.slack.golangbridge.org

The main real-time Go room has been administered by Gopher Academy since 2014. Request an invite through the form. The Go wiki names #general as the starting point. Many Go tools and projects keep their own channel here, so it doubles as the place where the ecosystem coordinates.

golang-nuts - Google Groups - groups.google.com/g/golang-nuts

The user mailing list and high traffic. Moderated, so a first post can take a day to appear. Project announcements land here regularly and get read.

golang-dev - Google Groups - groups.google.com/g/golang-dev

The language itself. Release candidates, freeze announcements, and compiler discussion. The Go 1.27 development freeze was announced here in May 2026. Bring your tool announcement to golang-nuts instead.

r/golang - Reddit - 97K members, 1.3K weekly contributions - reddit.com/r/golang

Linked from the official Go help page. The first two posted rules are to be friendly and be patient, with a note that not everyone posting is writing in their first language. Standing threads cover small projects, hiring, and frequently asked questions.

JavaScript and TypeScript

Reactiflux - Discord - 77.7K members - discord.gg/reactiflux

The largest React chat community, listed on react.dev as an official community venue. Covers React, React Native, Redux, Jest, Relay, and GraphQL. Volunteer-run since 2015, when Slack disabled its invites for having too many members and pushed them to Discord. Worth knowing that Reactiflux reports its own membership above 200,000, while Discord's public invite endpoint reports 77,754. We use the endpoint figure across all Discord entries for consistency.

TypeScript Community - Discord - 49.8K members - discord.gg/typescript

Linked from typescriptlang.org as the community chat. Active help channels staffed by people who know the type system deeply. Governance lives in a public repo, which is a good sign of a community that intends to outlast its founders.

OpenJS Foundation Slack - Slack - slack-invite.openjsf.org

The workspace for the foundation that hosts Node.js, jQuery, Electron, webpack, and Fastify. Project channels sit alongside working groups and collaboration spaces, so they are among the few places where maintainers across several major JavaScript projects are reachable in the same place. Open registration through the invite link.

Cloud native and Kubernetes

The largest professional developer communities in this directory are also the strictest.

Kubernetes Slack - Slack - over 200K members - slack.k8s.io

The main coordination platform for the Kubernetes project, with more than 170 channels covering every SIG. Invite-only through the community inviter, and no other route works. Read the guidelines before you post. Self-promotion is prohibited; surveys are confined to #surveys; and job posts go through a moderated queue in #kubernetes-careers using a structured form. The contributor documentation carries two different membership figures on the same page: 200,000 in the guidelines and 145,000 in a section about bots. We use the higher one because it appears in the current guidance.

CNCF Slack - Slack - slack.cncf.io

The sibling workspace for cloud native projects that are not Kubernetes itself. The Kubernetes Slack admins actively redirect projects here, so it is where you find the rooms for Prometheus, Envoy, Argo, Fulx and OpenTelemetry. Cross-referenced under observability and DevOps.

Docker Community Slack - Slack - dockercommunity.slack.com

Linked from docker.com's community page. The room covers container builds, Compose, and registry questions across topic-based channels, and it is where the Docker Captains show up to answer. Quieter than the Kubernetes workspace, which makes an individual's answer more visible.

r/kubernetes - Reddit - 66K members, 801 weekly contributions - reddit.com/r/kubernetes

The CNCF Code of Conduct applies here, which is unusual for a subreddit. Practitioners discuss cost and operational pain in the open, and those threads draw the heaviest engagement. Technical walkthroughs get posted and read. Marketing does not.

DevOps and platform engineering

DevOps Chat - Slack - roughly 19K members - devopschat.co

A general DevOps workspace with job listings and event announcements alongside technical discussion. Self-reported figure, since Slack does not publish counts.

r/devops - Reddit - 131K weekly visitors, 1.6K weekly contributions - reddit.com/r/devops

Read the rules before posting anything that includes your employer's name. Self-promotion, vendor posts, and personal affiliation all require disclosure under rule 4; job listings are pushed to r/devopsjobs, and low-effort content is removed under rule 5. There is a weekly self-promotion thread, and it is the correct place for your link.

AI and machine learning

This is the fastest-moving section in this directory, and the one where published member counts are least reliable.

Hugging Face - Discord - 226K members - hf.co/join/discord

The center of gravity for open machine learning. Paper reading groups, model releases, and course cohorts. Worth noting how badly the numbers lag elsewhere: Hugging Face's own course pages currently describe this server as having 18,000, 50,000, 90,000, and 100,000 members on different pages. The live figure is 226,276.

r/LocalLLaMA - Reddit - 847K members, 19,000 weekly - reddit.com/r/LocalLLaMA

The highest contribution volume of any community in this directory. People running models on their own hardware compare quantization, inference cost, and GPU builds, and new open models get benchmarked here before the coverage catches up. Standing megathreads track the best local LLMs, vision models, and speech models, and they are updated monthly.

r/MachineLearning - Reddit - 106K weekly visitors, 1.3K weekly contributions - reddit.com/r/MachineLearning

Research-weighted, and the moderation reflects it. Rules 1 through 3 prohibit spam, self-promotion, and marketing campaigns, with SEO named directly. Posts carry tags for projects, discussion, and research. Beginners are routed to r/mlquestions and career questions to r/cscareerquestions. A monthly self-promotion thread exists, and it is the only sanctioned route for your own work.

Data engineering

dbt Community - Slack - 77K members - getdbt.com/community

The default room for analytics engineering. Channels by tool, industry, methodology, and city, each with a named Community Maintainer responsible for keeping it alive. New channels go through #channel-requests. Note that dbt Labs and Fivetran completed their merger on 1 June 2026, first announced in October 2025, which is likely to shape how this community develops.

DataTalks.Club - Slack - 97K members - datatalks.club

Focused on practitioners rather than vendors. Runs open courses and a podcast. The low marketing-to-conversation ratio makes it a good place to build a reputation slowly.

r/dataengineering - Reddit - 127K weekly visitors, 1.5K weekly contributions - reddit.com/r/dataengineering

Pipelines, storage, modeling, and workflow engines. Technical blog posts do get posted and discussed here, tagged as blog content, which makes this one of the more permissive rooms in the directory for genuine writing. A monthly general discussion thread runs alongside.

Databases

Postgres shows the purpose split more clearly than any other technology here. The users moved to Discord, Reddit, and Stack Overflow, and the developers never left the mailing list, so if you want to reach the people building Postgres, the list is still the only room they are all in. The evidence for that comes from inside the project, and it closes this section.

People, Postgres, Data - Discord - discord.com/invite/bW2hsax8We

The main Postgres chat community, running across roughly 28 channels covering the wider ecosystem, including managed services. Deliberately mixes technical discussion with professional development and general conversation, so it reads less like a support desk than most database rooms.

r/PostgreSQL - Reddit - 32K weekly visitors, 238 weekly contributions - reddit.com/r/PostgreSQL

Smaller than the language subreddits and unusually tolerant of people posting their own work, provided they flair it and disclose their employer. Recent front-page posts include a podcast episode by a vendor employee under a marketing flair, which was upvoted rather than removed. The two headline rules are be nice and be helpful.

Where the Postgres developers went

Worth understanding before you plan anything for a Postgres audience. Core committer Peter Eisentraut counted the traffic on the project mailing lists and found the split in numbers in a December 2024 post titled Where are all the PostgreSQL users? In November 2004, pgsql-general carried 1,507 messages. In November 2024, it carried 445. Over the same period, pgsql-hackers, where development happens, went from 1,300 to 2,279. The users moved to Discord, Reddit, and Stack Overflow. The developers never left the list.

Security

OWASP Slack - Slack - over 44K members - owasp.org/slack/invite

Organized by chapter and by project, which is unusual and useful. #project-genai and #project-ai-community are currently among the most active, as the application security world works out how AI-generated code affects its threat models. Local chapter channels make this one of the few communities here where an online conversation reliably turns into an in-person one.

r/netsec - Reddit - 22K subscribers - reddit.com/r/netsec

It is smaller than its influence suggests, and curated hard. The stated mission is to extract signal from noise for practitioners and researchers, and the first rule requires linking to the original source rather than to coverage of it. Vulnerability write-ups and original research do well. Quarterly hiring threads and a monthly tool thread carry everything else.

Mobile

iOS Developers Slack - Slack - roughly 40K members - ios-developers.io

Read the entry requirements before you plan anything here. This community is invite-vouched. An existing member in good standing must invite you; they may invite up to two people per calendar month, and they are responsible for your conduct. The code of conduct is explicit that you should invite people you have worked with or know personally, not strangers. It is one of the highest-quality rooms in this directory and one of the least accessible, and those two facts are related.

Swift Forums - Discourse - forums.swift.org

The official discussion venue for Swift, and swift.org says so plainly. Evolution proposals, compiler development, and a section explicitly set aside for beginner questions. Public, searchable, and the closest thing Apple's ecosystem has to an open front door.

r/androiddev - Reddit - 67K weekly visitors, 1,000 weekly contributions - reddit.com/r/androiddev

Weighted toward working professionals handling platform changes and Play Store policy. Account restrictions and identity verification problems surface here first, often within hours. A monthly thread rounds up interesting apps, and the sidebar links to a companion Discord.

Java and the JVM

Together Java - Discord - over 44K members - togetherjava.org

The main live Java chat is active. Self-help oriented, with a culture of working through a problem alongside the person asking rather than handing over a finished answer. Questions get picked up rather than scrolling away.

r/java - Reddit - 44K weekly visitors, 639 weekly contributions - reddit.com/r/java

Read the sidebar before you post anything. This subreddit takes news, technical discussion, and research papers, and it explicitly refuses programming help, learning questions, install questions, and other JVM languages. A pinned notice saying so has 324 upvotes. Tutorials are named as unwelcome and redirected to r/learnjava. Bring release analysis or ecosystem news.

PHP

PHP Slack - Slack - phpchat.co

A real-time Slack for PHP programmers, generally not tied to any single framework. Channels are split into announcements, a general programmers' hangout, an off-topic room kept separate so the working channels stay focused, and a channel for trading feedback on your own projects. The register is casual, and the help is peer-to-peer rather than staffed, so it rewards people who stick around and answer as much as they ask.

Symfony Slack - Slack - symfony.com/slack-invite

The symfony-devs workspace, reachable through the invite on Symfony's site. Beyond Symfony itself, it hosts channels for projects built on the framework, including API Platform, so it doubles as the coordination point for a chunk of the modern PHP ecosystem. Bring framework questions and contribution discussion. The wider Symfony community spans more than 120 countries, and Slack is its real-time layer.

r/PHP Reddit - 25K weekly visitors, 503 weekly contributions - reddit.com/r/PHP

Ecosystem news rather than support, with help posts banned under rule 4 and pushed to a weekly help thread. A standing "Pitch Your Project" thread gives self-promotion a sanctioned home, which is rarer than it should be. Conference calls for papers and language proposals get real discussion here.

Wrapping up

If your goal is simply to get your product in front of developers as quickly as possible, you're solving the wrong problem. The communities worth joining reward consistent contribution and quickly push back against people who show up only to distribute content

This is how we work at Hackmamba - we spend time in these rooms as developers first, answering questions in the stacks we know, because that is what earns the standing to be heard later. The distribution is a by-product of being useful. When it is the reason for showing up, developers can tell, and it stops working. A directory like this one is only as good as what you do with it, and the teams that treat these communities as places to have real conversations with engineers are the ones those engineers eventually remember.

If you want to build that kind of presence instead of burning budget chasing attention, that's exactly what we help companies do.

We now offer content distribution as a standalone service, not just as part of our content marketing offering. We help developer-first companies distribute technical content that reaches millions of impressions and thousands of high-intent clicks.

If you're looking to get more from the content you've already invested in, get in touch. We'd be happy to show you how.