Open Source Conferences and Events

Major Global Conferences

FOSDEM

FOSDEM (Free and Open Source Developers' European Meeting) is one of the world's largest and oldest open source gatherings, held every winter at the Universite libre de Bruxelles in Belgium. The event is entirely free to attend with no registration required, funded by sponsors and volunteer labor. FOSDEM 2026 featured over 600 talks across more than 80 developer rooms, each organized by a specific project or technology community. Developer rooms cover everything from Rust and Go to containers, security, and community management.

What makes FOSDEM distinctive is its grassroots character. There is no corporate sponsor keynote stage, and the event is organized entirely by volunteers. The hallway track, informal conversations between sessions, is famously productive, and many cross-project collaborations have started over coffee at FOSDEM. The event also serves as a meeting point for European open source developers and advocates, making it a natural venue for community planning and governance discussions.

KubeCon + CloudNativeCon

KubeCon + CloudNativeCon is the flagship event of the Cloud Native Computing Foundation and the largest conference dedicated to cloud-native technologies. The event runs three times per year: in North America (typically in the fall), Europe (spring), and Asia. The North American edition regularly draws over 12,000 in-person attendees, with thousands more joining virtually.

KubeCon covers the entire CNCF ecosystem, including Kubernetes, Prometheus, Envoy, Helm, Argo, Cilium, and dozens of other projects at various maturity levels. The schedule includes keynotes, breakout sessions, tutorials, lightning talks, and project pavilions where maintainers demonstrate their software and recruit contributors. Co-located events include Contributor Summits (dedicated working time for project maintainers), the ServiceMeshCon, the Observability Day, and the Security Day, each focused on a specific technology area.

In 2026, KubeCon has also co-located with PyTorch Conference and OpenInfra Summit events at several of its venues, reflecting the growing convergence between cloud-native infrastructure and AI workloads. This co-location brings together communities that previously attended separate events, creating new opportunities for cross-pollination between infrastructure engineers and machine learning practitioners.

Open Source Summit

The Open Source Summit, organized by the Linux Foundation, is a family of events held in North America, Europe, and Japan. Rather than focusing on a single technology area, the Summit brings together communities from across the open source landscape under one roof. Tracks cover embedded Linux, cloud infrastructure, networking, AI and data, security, and open source leadership and community management.

The Summit often co-locates with more specialized events like the Embedded Linux Conference, the Linux Security Summit, and the Open Source Leadership Forum. This co-location model means attendees can engage with their primary community while also exploring adjacent areas. For organizations that contribute to multiple open source projects, the Summit provides a single event where teams across different technology areas can connect.

Language and Framework Conferences

PyCon

PyCon US is the largest annual gathering of the Python community, typically drawing over 3,000 attendees. Organized by the Python Software Foundation, the event includes tutorials, talks, poster sessions, open spaces (unconference-style discussion rooms), and a development sprint that runs for several days after the main conference. PyCon is known for its welcoming atmosphere and its emphasis on diversity, with financial aid programs that help attendees from underrepresented groups participate.

Beyond PyCon US, the Python community runs PyCon events in dozens of countries, each organized by local community volunteers. PyCon India, EuroPython, PyCon APAC, and PyCon Africa are among the largest regional events. These events serve as hubs for local Python communities and often feature talks and workshops tailored to regional interests and industries.

RustConf and RustNation

The Rust programming language community runs several conferences, including RustConf (primarily North American) and RustNation UK. These events cover the Rust language itself, its tooling ecosystem, and the wide range of domains where Rust is being adopted, from systems programming and embedded development to web services and game engines. The Rust community's conference culture reflects the language community's values of inclusivity and technical rigor, with detailed codes of conduct and strong emphasis on mentorship.

SCALE

The Southern California Linux Expo (SCALE) is the largest community-run open source conference in North America. Held annually in Pasadena, SCALE features a broad program covering Linux, DevOps, security, networking, and community management. The event has a reputation for being affordable and welcoming to newcomers, making it a popular first conference for people new to the open source world. SCALE also hosts focused tracks organized by specific communities, including an UpSCALE track for students and a Kids Can Hack area for young learners.

Foundation and Ecosystem Events

CommunityOverCode

CommunityOverCode (formerly ApacheCon) is the official conference of the Apache Software Foundation. The event rotates between North America, Europe, and Asia, bringing together contributors and users of the 320+ Apache projects. Unlike technology-focused conferences, CommunityOverCode emphasizes the community aspects of open source as much as the technical ones. Sessions on governance, mentorship, community health, and the Apache Way sit alongside talks on specific Apache projects like Kafka, Spark, and Airflow.

Eclipse Foundation Events

The Eclipse Foundation organizes EclipseCon and related events focused on the Eclipse IDE ecosystem, Jakarta EE (enterprise Java), and the foundation's IoT and automotive projects. Based in Brussels, the Eclipse Foundation has become a hub for European open source governance, and its events reflect the intersection of open source technology with EU regulatory concerns like digital sovereignty and data protection.

Contributor Sprints and Hackathons

Sprints and hackathons are intensive, focused events where contributors work together on specific goals. Unlike conferences, which emphasize talks and networking, sprints are about getting code written, documentation improved, and issues resolved. Many conferences run sprints alongside or after the main event, giving attendees a chance to turn the ideas and connections from conference talks into concrete contributions.

The Python community is particularly active in running sprints. PyCon US includes a multi-day development sprint after the conference, where core Python developers, library maintainers, and newcomers work side by side on the CPython interpreter, popular libraries, and community infrastructure. Django, NumPy, and scikit-learn regularly run dedicated sprints at PyCon and other events, providing newcomers with hands-on mentorship from experienced contributors.

Google Summer of Code (GSoC) and Outreachy are not events in the traditional sense but structured programs that create similar intensive contribution experiences. GSoC pays university students to work on open source projects over the summer, with mentorship from project maintainers. Outreachy provides paid internships in open source for people from underrepresented groups. Both programs have introduced thousands of new contributors to open source communities and have become important pipelines for diverse talent.

Regional and Local Events

Beyond the major international conferences, a rich ecosystem of regional and local events sustains open source communities at the grassroots level. Linux User Groups (LUGs), DevOps meetups, language-specific user groups, and hackerspaces provide regular in-person gathering points for local communities. These events are often free, informal, and focused on learning and networking rather than vendor presentations.

Regional conferences like FOSS Asia (Southeast Asia), Open Source Africa, linux.conf.au (Australia and New Zealand), and GUADEC (GNOME Users and Developers European Conference) serve communities that may not have the resources to travel to the major international events. These events play a critical role in building open source capacity in regions that are underrepresented in the global open source community, and they often feature content tailored to local industries, languages, and regulatory environments.

Getting the Most from Open Source Events

To maximize the value of attending an open source conference, go with specific goals. Identify sessions, speakers, and projects you want to learn about before the event. If you want to contribute to a project, attend its contributor summit or sprint. If you want to meet people in a specific community, check the event schedule for Birds of a Feather (BoF) sessions, open spaces, or community meetups.

The hallway track, conversations between sessions, is often the most valuable part of any conference. Introduce yourself to speakers after their talks, join groups at lunch, and attend social events. Many attendees report that the relationships they build at conferences are more valuable than the technical content, because those relationships turn into mentorship, collaboration, and job opportunities that persist long after the event ends.