Semaphore Uncut

A new open source release of Semaphore is almost here. Version 1.6 lands exactly one year after 1.5 and packages up around 494 pull requests of work from the past year. Here’s what’s inside.

AI and automation, built in

The MCP server now ships in the open source editions. It’s included in both the Community Edition and the Enterprise Edition.

sem-ai works out of the box. It’s fully supported with no additional configuration needed, and works with both service accounts and user tokens.

Almost everything is now configurable through the API. New public API endpoints cover artifacts, plus pre-flight checks in the Enterprise Edition. Between sem-ai and the regular API endpoints, you can now configure almost everything in Semaphore programmatically.

Pipeline improvements

Partial job reruns are here. For very long and complex pipelines, not everything needs to be rerun anymore.

New filtering options in the UI. Finding what you need in your pipelines is now easier.

Under the hood

RustFS replaces MinIO as the artifact storage engine. With MinIO moving away from the open source community, we switched to RustFS. It also powers our tests.

Security fixes and improvements. The release includes a lot of security fixes and general improvements across the board.

What’s Coming

The release candidate will be ready in the next couple of days, along with the full extended changelog.

Get involved

We accept PRs from the community. Open an issue or a PR on the Semaphore repository and share your comments and suggestions. All contributions and feedback are very welcome.

* Try sem-ai

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* All product news

Till the next time,

Pete Miloravac

https://semaphore.io

AI coding agents can generate and modify code quickly. But to work effectively with CI/CD, they need focused information, clearly defined permissions, and safeguards that prevent unsuitable changes from progressing.

The new sem-ai 0.4.0 release improves all three areas.

In our latest product news video, Nick demonstrates more compact pipeline responses, flexible context switching, and the ability to create and validate Semaphore preflight checks directly with an AI coding agent.

Get the essential pipeline information

Requests for Semaphore workflows and pipelines now return a much more compact response by default.

In the demonstration, the new response was approximately 99 percent smaller than the previous full output. This gives an AI coding agent the essential pipeline information without filling its context window with unnecessary detail.

The complete output is still available when needed. Results can also be limited or filtered by date.

This makes sem-ai more efficient by default while giving developers control over how much information the agent receives.

Switch between permission contexts

sem-ai 0.4.0 also introduces a context flag.

You can define separate contexts for different Semaphore organizations or service accounts, then select the appropriate one through a command line flag or an environment variable.

For example, one service account could have read only access for reviewing code and investigating pipeline failures. Another could have permission to modify Semaphore configuration.

This supports a safer, least privilege approach. An AI agent receives the access required for its current task without automatically receiving broader control.

Create preflight checks with your coding agent

The release also adds support for Semaphore’s preflight checks API.

Preflight checks evaluate a request before a workflow starts. Teams can use them to enforce organizational rules, including required branch naming conventions.

In the video, Claude Code creates a preflight check for a Semaphore project. It configures a branch naming rule, adds the check, and tests it against several branches.

Workflows from accepted branches continue normally. Branches that do not follow the required pattern are blocked before the pipeline begins.

This gives teams another way to turn delivery policies into enforceable safeguards, directly from the development environment where the agent is working.

One limitation remains. The init job configuration used by preflight checks cannot yet be modified programmatically. The Semaphore team plans to address this in a future update.

sem-ai 0.4.0 is available now

Plugins for Claude Code and Codex will update automatically.

If you use the sem-ai command line interface directly, it will notify you when the new version is available and provide the command needed to install it.

Watch the full demonstration to see sem-ai 0.4.0 in action.

Explore the project on GitHub, or create a Semaphore account to try it with your own pipelines.

A pipeline fails on a single job, and you shouldn’t have to rebuild everything around it to recover. That’s what changes with this update.

Job rerun is here, and it reruns only the jobs that actually failed. Until now, when a job inside a block failed and you reran the pipeline, every job in that block got rebuilt, including the ones that had already passed. The new default rebuilds only the failed jobs. Every other job in the block, plus jobs from earlier in the pipeline, is carried over and reused, so your workflow topology stays intact and only the new jobs get built.

The carried-over jobs are excluded from your billable time. That means a rerun costs you only the jobs that failed, not the whole block. Faster turnaround on failures, and a lower bill to match.

The old behavior is still one flag away. We exposed a YAML flag called block rebuild that keeps the full block rebuild when you want it. The new, leaner path is the default, and the escape hatch is there when you need it. sem-ai already understands the new behavior, so agents pick it up and rerun the right way automatically.

What’s Coming

Job rerun is the first building block of doubling down on CI for the second half of 2026. We’re working through what CI looks like in an agent-driven software development world, with sem-ai as the agent-native interface to the CI. Expect more agentic CI capabilities announced through September.

* Try sem-ai

* Try Semaphore Cloud

* All product news

Till the next time,

Pete Miloravac https://semaphore.io

Flaky test data is now accessible through the sem-ai API, and this week also brings a skill that uses that data to fix the tests automatically.

Flaky test data is now generally available through the API. You can query your flakiest tests programmatically, sorted by number of disruptions, with failure timestamps and logs included. Find it on github.

A new sem-ai skill can identify and fix flaky tests end-to-end. The agent pulls the highest-disruption tests, gathers failure context, determines the root cause, and writes a fix. It then verifies the result, first by running tests locally, and if that’s not possible, by spinning up Semaphore test boxes to run the test across multiple machines in parallel. Running the test repeatedly across machines is especially important for flaky tests, since a single passing run isn’t enough to confirm a fix. Benchmarking on a real open source project with Claude Opus on high effort showed a cost of $1 to $1.50 per fix.

Four existing skills were improved with additional examples. Agents were occasionally not following skill instructions due to a lack of examples. Adding concrete examples improves adherence and makes sem-ai’s output more consistent across runs.

What’s Coming

User and organization management will be added to the API in an upcoming release. The team is also continuing to refine skills and commands based on usage patterns.

* Try sem-ai

* Try Semaphore Cloud

* All product news

Till the next time,

Pete Miloravac https://semaphore.io

Here’s an update on what our engineering team has been shipping in sem-ai and what’s coming up next.

Codex marketplace support is live.A few issues were blocking some users from getting sem-ai working on Codex. Those are now fixed. If you tried it before and hit a wall, it’s worth giving it another shot.

Task creation got faster.We cleaned up some unnecessary API calls that were causing hiccups. You can now create and manage tasks on your projects entirely through the CLI, exactly where your agent already lives.

sem-ai plugin submitted to the Claude marketplace.We’re in review. We’ll share more once it’s through.

On the horizon:The team is working on full platform management through sem-ai. Members, organizations, and everything else currently in the Semaphore UI will be accessible directly through the CLI.

Also shipped: Show/hide skipped blocks in the workflow editor is now generally available. If you work with complex pipelines, it makes reading results a lot cleaner.

We’ve been talking a lot recently about AI-native developer workflows and where CICD is heading. This week, we shared one of our most exciting demos yet: a look at how SEMai is changing the way developers interact with CICD systems.

In the demo, Marcos starts with a completely clean repository: no CI configuration, no GitHub Actions workflows, nothing.

Then, inside Claude Code, he runs a single command:

/sem-ai init

From there, sem-ai analyzes the repository, detects the tech stack, and generates a tailored CICD pipeline automatically.

It recommends:

* Linting

* Security scanning

* Matrix testing

* Pipeline topology improvements

But the most interesting part comes afterward.

Marcos tells the agent:

“Work until the pipeline is green.”

The system monitors the pipeline, analyzes failures, applies fixes, reruns workflows, and eventually gets the build passing successfully while summarizing everything it changed along the way.

Nick also shares lessons learned while building the onboarding experience itself, including why slash commands became critical for reliable agent workflows and how improving contextual skills dramatically increased success rates.

This is what we mean when we talk about AI-native CICD:not AI bolted onto existing tooling, but a fundamentally different developer experience built around collaboration between developers and agents.

In the full demo, Marko, Marcos, and Nick walk through:

* AI-assisted CICD onboarding

* Slash command workflows

* Self-healing pipelines

* Pipeline optimization

* The evolution of SEMai skills and agent context

We’re excited about where this is heading and look forward to sharing more soon.

Pete Miloravachttps://semaphore.io

Developers are increasingly working inside AI-powered coding tools like Claude Code, Cursor, and Codex.

The workflow is changing.

Instead of constantly switching between dashboards, logs, terminals, and configuration files, developers are starting to collaborate directly with coding agents using natural language.

We think CI/CD should evolve alongside that shift.

Today, we’re introducing Semaphore for AI Agents — a new open-source CLI and agentic interface designed to make Semaphore fully accessible from AI coding agents.

This is the first step toward what we call the AI-native Semaphore experience.

What is Semaphore for AI Agents?

Semaphore for AI Agents gives coding assistants a structured way to interact with Semaphore.

Instead of manually navigating CI/CD systems, developers can simply ask:

* “Why is my CI failing?”

* “What tests are flaky?”

* “Show me the critical path in this pipeline.”

* “Summarize the health of this project.”

And their coding agent can retrieve, analyze, and act on that information directly through Semaphore.

The first release includes:

* Pipeline diagnostics

* Flaky test detection

* Critical path analysis

* Organization-wide CI/CD insights

* MCP support

* Claude Code integrations

* Remote execution workflows on Semaphore infrastructure

We also demonstrate how developers can provision ephemeral machines for agent-driven workflows, remote testing, and scalable execution.

Built for Agentic Workflows

Semaphore for AI Agents was designed specifically for AI-native development workflows.

The project ships with:

* Agent-oriented commands

* Structured JSON outputs

* Claude Code skills

* Generic agent skills

* A local MCP server

This allows coding assistants to interact directly with Semaphore while developers stay inside their coding environment.

Fully Open Source

Semaphore for AI Agents is fully open source.

Developers can inspect how it works, extend workflows, contribute new commands, and build their own automations.

We believe AI-powered developer tooling should remain transparent, inspectable, and developer-controlled.

This Is Just the Beginning

Semaphore for AI Agents is the foundation for a broader direction we’re building toward at Semaphore:

* Developers define intent

* Agents handle repetitive execution

* Semaphore provides the infrastructure and orchestration layer

Over the coming weeks, we’ll continue shipping new workflows, MCP capabilities, testing automation, and scalable agent execution features.

Watch the Demo

We recorded a full walkthrough showing:

* CI/CD debugging workflows

* MCP integrations

* Claude Code usage

* Organization-wide insights

* Remote execution on Semaphore infrastructure

→ [Read the full blog post]

Thanks for following along.

Till the next product update.

Pete Miloravachttps://semaphore.io

Modern development teams don’t all build on the same stack and they should not have to.

Today, we are expanding Semaphore’s capabilities to better support teams building on the Microsoft ecosystem, with first class support for the .NET framework and Microsoft Edge in CI pipelines.

This marks an important step toward making Semaphore a truly flexible platform for all developers, regardless of their technology choices.

Supporting More Developers, Where They Work

Until now, Semaphore has primarily focused on Linux native tooling and ecosystems. With this update, we are extending that foundation to support developers working with the Microsoft stack.

This includes:

* .NET SDK support for building and compiling applications in CI

* Microsoft Edge browser support for running end to end and UI tests

* Full compatibility within Semaphore pipelines running on Linux

By enabling these tools, teams can now build, test, and validate .NET applications directly within Semaphore, without workarounds or custom environments.

Built on a Familiar, Reliable Foundation

This new support is already available in production, as part of our latest updates (see the changelog), and works on our latest Ubuntu 24.04 image.

You can learn more about the environment here.

By leveraging Linux compatible tooling for the Microsoft ecosystem, we are making it possible to run .NET workloads in the same scalable, reliable CI/CD environment teams already use for other stacks.

This approach keeps things simple:

* No need to manage separate CI systems

* No need to maintain custom infrastructure

* No disruption to existing workflows

Just a consistent, unified pipeline experience.

Why This Matters

As development ecosystems continue to evolve, teams are increasingly working across multiple stacks and technologies.

Supporting .NET is not just about adding another SDK. It is about expanding what developers can do within a single CI/CD platform.

This aligns directly with our broader vision:

* Reduce friction in software delivery

* Automate the repetitive work behind building and testing

* Let developers focus on what actually matters

As outlined in our 2026 product strategy, our goal is to remove unnecessary toil and make the right thing the easy thing inside CI/CD .

Bringing .NET into Semaphore is one more step toward that goal.

What’s Next

We have also prepared a simple demo project showcasing how to build and test a .NET application on Semaphore. You can access it here.

Alongside that, documentation updates and image changes are already available, and we will continue improving the experience based on feedback.

This is just the beginning.

As we continue expanding language and ecosystem support, our focus remains the same. Helping developers ship high quality software faster, with less manual effort.

Happy building!Pete Miloravac Semaphorehttps://semaphore.io

As AI agents become part of everyday development workflows, authentication is becoming a critical piece of the puzzle.

In our latest product update, we’re sharing a behind-the-scenes look at how we implemented OAuth for Semaphore’s MCP server—and what we learned along the way.

You’ll get a practical perspective on:

* Why OAuth is essential for MCP and AI agents

* The challenges of working with evolving specs and inconsistent agent behavior

* What actually works in real-world implementations

* Key lessons for building secure, reliable integrations

This isn’t theory—it’s a real engineering deep dive from our team.

👉 Read the full blog post👉 Watch the full video

This work is part of a broader shift at Semaphore, where we’re extending CICD with AI-powered workflows—while keeping developers in control and reducing manual work.

If you’re building with MCP or exploring agent-driven workflows, this one’s worth your time.

— Pete MiloravacThe Semaphore Teamhttps://semaphore.io

Today we’re introducing an important change to how Semaphore pricing works.

CICD is no longer something that runs occasionally during development. For many teams, it’s now always-on infrastructure that powers software delivery.

To support this shift, we’re introducing a new Semaphore pricing model designed to keep CICD fast, scalable, and affordable as usage grows.

What’s changing

The new model separates compute infrastructure from support and success services, giving teams more transparency and flexibility in how they use Semaphore.

Key updates include:

Lower machine pricing

Semaphore’s fastest runners are now available at significantly reduced prices, starting at $0.0075 per minute.

Our new f1 machines replace the previous e1 and e2 runners, focusing the platform on high-performance compute optimized for CICD workloads.

Usage-based pricing for self-hosted agents

Self-hosted agents are no longer billed per developer seat.Instead, usage is priced purely based on compute time at $0.0025 per minute.

Support and success plans are now separate

Infrastructure pricing now reflects compute consumption only.Teams can choose optional Support and Success plans depending on their operational needs and level of optimization guidance.

A modular approach to CICD

Teams can now combine:

* Compute infrastructure

* Support plans for operational reliability

* Success plans for performance optimization

* On-demand engineering assistance

This modular model makes it easier to scale Semaphore alongside your CICD usage.

For existing customers

Nothing changes immediately.

You can continue using your current plan as-is, and when you’re ready, you’ll be able to switch to the new pricing structure directly in the app.

Learn more

You can explore the full pricing details here:

👉 Pricing page👉 Try out Semaphore

If you have any questions, drop us an email at [email protected]

The Semaphore Team