How does Atlas ensure the automated responses are specific to my Haskell project's style?

Atlas ensures responses adhere to your Haskell project's style by applying `fourmolu` to any changed modules before proposing a commit. It also reads your `.cabal` file to understand language extensions and build dependencies, ensuring contextual awareness.

Can Atlas fix GHC type errors in my Haskell code automatically?

Yes, Atlas can iterate on proposed diffs to eliminate GHC type errors. It runs `cabal build` to surface these errors and continues refining the code until it typechecks, presenting the final diff for your approval.

What if an untrusted user tries to trigger Atlas on my Haskell repository?

Atlas performs a crucial security check: it verifies the triggering actor's collaborator permission. If the actor does not have `admin` or `write` permission on the repository, Atlas will refuse to run, ensuring only trusted users can initiate automated triage.

How does Atlas handle large Haskell codebases or complex issues that might exceed context limits?

Atlas explicitly handles context overflow. If a prompt becomes too large, it catches a `ContextOverflowError` by name and re-throws it as a prompt-too-large message, listing the offending files so you can address the scope.

Does Atlas require my Haskell code to be sent to third-party servers for indexing?

No, Atlas can build its code index with local Ollama embeddings. This capability keeps your Haskell code off third-party servers, maintaining privacy and control over your intellectual property.

How can I review the changes Atlas proposes before they are committed to my Haskell project?

Atlas computes a unified diff for every file edit it proposes and surfaces it for your approval before writing any changes. This allows you to review and accept or reject the modifications to your Haskell codebase.

What Haskell-specific information does Atlas use to reason about my code?

Atlas reasons about your Haskell code by reading your `.cabal` file or `stack.yaml`, understanding your module hierarchy, `default-extensions`, and `build-depends` bounds. It uses AST declarations via tree-sitter to understand type signatures and typeclass instances.

Automate GitHub Issue and Pull Request Triage in Haskell with Atlas in 2026

In 2026, Haskell developers can automate GitHub issue and pull request triage safely and only for trusted users by integrating Atlas directly into their GitHub workflows. Atlas leverages the Haskell toolchain, including `cabal` for builds and `fourmolu` for formatting, to ensure responses are contextually aware and adhere to project standards.

How does Atlas automate GitHub triage for Haskell projects?

Atlas automates GitHub issue and pull request triage for Haskell projects by integrating directly into GitHub Actions workflows, requiring specific inputs like a `MODEL` and `PROMPT`. In 2026, this ensures that only trusted users can trigger responses, with Atlas performing initial checks on actor permissions.

Atlas provides a first-class GitHub entrypoint via the `atlas github` command, designed to read its inputs directly from the GitHub Actions environment. For automated triage, it strictly requires a `MODEL` in `provider/model` form and a `PROMPT` for specific event types that need one; anything else is rejected upfront. Before any action, Atlas performs a critical security check, verifying that the triggering actor possesses `admin` or `write` collaborator permission on the Haskell repository. If these permissions are not met, Atlas refuses to run. Furthermore, to prevent unintended runs from stray comments, the handler enforces that comments must explicitly mention the configured trigger. Should the context for an issue or pull request exceed processing limits, a `ContextOverflowError` is caught by name and re-thrown as a prompt-too-large message, listing the offending Haskell files.

How does Atlas understand Haskell codebases?

Atlas understands Haskell codebases by building its code index with AST declarations using tree-sitter, not blind line windows, a capability available in 2026. This allows Atlas to reason about type signatures, typeclass instances, and Cabal targets, providing precise context for issue triage.

To effectively reason about Haskell code, Atlas requires a project to contain a `.cabal` file or a `stack.yaml`. Once configured, Atlas reads your module hierarchy, language extensions specified in `default-extensions`, and `build-depends` bounds, providing a deep understanding of your project's structure and dependencies. This detailed indexing, which can be built with local Ollama embeddings to keep your Haskell code off third-party servers, enables Atlas to perform sophisticated tasks. For instance, it can be asked to eliminate a partial function within a module or add an `hspec` suite to a `test-suite` stanza in your `.cabal` file, demonstrating its ability to interact meaningfully with Haskell idioms and project configurations.

What are the concrete Haskell commands Atlas uses for verification?

Atlas uses concrete Haskell commands like `cabal build` to surface GHC type errors and `fourmolu` for code formatting, ensuring code quality in 2026. This iterative process allows Atlas to propose changes, verify them against the project's toolchain, and present a unified diff for approval.

When Atlas proposes changes to a Haskell codebase, it integrates directly with the standard Haskell toolchain for verification. It will run `cabal build` to compile the project and surface any GHC type errors. If errors are found, Atlas iterates on the proposed diff, refining the code until it successfully typechecks. This ensures that any automated modifications maintain the project's integrity. Before presenting the final changes for approval, Atlas applies `fourmolu` to the changed Haskell modules, guaranteeing adherence to the project's formatting standards. This combination of `cabal build` for correctness and `fourmolu` for style ensures that all Atlas-generated code is production-ready and consistent with existing Haskell practices.

How does Atlas ensure safety and review for automated Haskell changes?

Atlas ensures safety and review for automated Haskell changes through a multi-stage approval process, including permission-gated tool calls and unified diffs, a core feature in 2026. Every Atlas tool call is permission-gated against allow, ask, and deny rules before it runs, providing granular control.

Safety is paramount in Atlas's operation. Every tool call it makes, whether `bash`, `read`, `grep`, or `edit`, is permission-gated against configurable allow, ask, and deny rules before execution. This provides fine-grained control over what actions Atlas can take within your Haskell project. Atlas drafts its initial plan in a read-only plan agent and explicitly asks for approval before switching to a build agent to make changes. For every file edit, Atlas computes a unified diff and surfaces it for your approval, allowing you to review the exact modifications to your Haskell code. Atlas also reads `git` branches, status, and diffs, and can stage and create commits on your behalf, but only after your explicit approval. Furthermore, it snapshots file changes as `git` patches, enabling easy diffing and rollback of any edits.

Step by step

01Configure a GitHub Actions workflow file (e.g., `.github/workflows/atlas-triage.yml`) to invoke the `atlas github` command for your Haskell repository.
02Set the `MODEL` input in `provider/model` form within your workflow, ensuring Atlas can access the specified model for processing Haskell issues and pull requests.
03Provide the `PROMPT` input for specific event types that require it, such as new issues or pull requests, to guide Atlas's initial response for your Haskell codebase.
04Ensure the triggering actor has `admin` or `write` collaborator permission on the Haskell repository, as Atlas will refuse to run otherwise for security.
05Configure the workflow to require a specific mention in comments (e.g., `@atlas triage`) to prevent unintended runs from stray comments on Haskell issues.
06Let Atlas run `cabal build` to identify and surface any GHC type errors in proposed Haskell changes, iterating until the code typechecks.
07Approve Atlas's proposed diffs after it has iterated on the code to achieve typechecking and applied `fourmolu` formatting to the Haskell modules.
08Atlas will then stage and create commits on your behalf, incorporating the verified and formatted Haskell changes into your repository.

Frequently asked questions

How does Atlas ensure the automated responses are specific to my Haskell project's style?: Atlas ensures responses adhere to your Haskell project's style by applying `fourmolu` to any changed modules before proposing a commit. It also reads your `.cabal` file to understand language extensions and build dependencies, ensuring contextual awareness.
Can Atlas fix GHC type errors in my Haskell code automatically?: Yes, Atlas can iterate on proposed diffs to eliminate GHC type errors. It runs `cabal build` to surface these errors and continues refining the code until it typechecks, presenting the final diff for your approval.
What if an untrusted user tries to trigger Atlas on my Haskell repository?: Atlas performs a crucial security check: it verifies the triggering actor's collaborator permission. If the actor does not have `admin` or `write` permission on the repository, Atlas will refuse to run, ensuring only trusted users can initiate automated triage.
How does Atlas handle large Haskell codebases or complex issues that might exceed context limits?: Atlas explicitly handles context overflow. If a prompt becomes too large, it catches a `ContextOverflowError` by name and re-throws it as a prompt-too-large message, listing the offending files so you can address the scope.
Does Atlas require my Haskell code to be sent to third-party servers for indexing?: No, Atlas can build its code index with local Ollama embeddings. This capability keeps your Haskell code off third-party servers, maintaining privacy and control over your intellectual property.
How can I review the changes Atlas proposes before they are committed to my Haskell project?: Atlas computes a unified diff for every file edit it proposes and surfaces it for your approval before writing any changes. This allows you to review and accept or reject the modifications to your Haskell codebase.
What Haskell-specific information does Atlas use to reason about my code?: Atlas reasons about your Haskell code by reading your `.cabal` file or `stack.yaml`, understanding your module hierarchy, `default-extensions`, and `build-depends` bounds. It uses AST declarations via tree-sitter to understand type signatures and typeclass instances.

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