How does Atlas detect a hanging `go test (app.Test)` in Fiber?

Atlas detects a hanging `go test (app.Test)` by running it through its `bash` tool with a timeout. If the command exceeds this timeout, Atlas terminates it and provides `shell_metadata` that explicitly states whether the `go test` was genuinely slow or blocked on interactive input, which is crucial for Fiber test suites.

What if my `go mod tidy` command is blocked on input in a Fiber project?

If Atlas's `shell_metadata` indicates your `go mod tidy` command is blocked on input, you should re-run it using Atlas's `bash` tool with the `-y` flag: `bash "go mod tidy -y"`. This provides a non-interactive 'yes' response, allowing the `go mod` operation to complete without user intervention in your Fiber module.

Can Atlas help with `fasthttp` buffer reuse issues in Fiber handlers?

Yes, Atlas can help. Given that `fasthttp` reuses underlying buffers, if you retain a `fiber.Ctx` value past its handler, Atlas can be asked to copy that `ctx` value. This prevents unexpected behavior or hangs related to buffer reuse, leveraging Atlas's ability to read `fiber.Ctx` handlers and propose code changes.

How do I increase the timeout for a slow `gofmt` operation in Fiber?

If Atlas diagnoses a `gofmt` operation as genuinely slow, you can increase its timeout by specifying the `--timeout` flag with a larger value in milliseconds when running it via Atlas's `bash` tool. For example, `bash --timeout 30000 "gofmt -w ."` would allow 30 seconds for the formatter to complete across your Fiber project.

What safety features does Atlas offer when modifying Fiber code?

Atlas offers several safety features for Fiber code modifications: permission-gated tool calls, a read-only plan agent for drafting changes, unified diffs for every file edit requiring your approval, and git patch snapshots for easy rollback. This ensures all changes to your `app.Group` routes or `fiber.Ctx` handlers are transparent and controlled.

Does Atlas work with `go.mod` dependencies for Fiber projects?

Yes, Atlas works direct with `go.mod` dependencies. It can be run in a module whose `go.mod` requires `github.com/gofiber/fiber/v3`. Atlas can diagnose hanging `go mod` commands and, with your permission, even propose changes to your `go.mod` file or run `go mod tidy` to manage dependencies for your Fiber application.

How does Atlas distinguish a user-aborted Fiber command from a timeout?

Atlas clearly distinguishes between a user-aborted command and a timeout. If you manually interrupt a `go test` or `go mod` command running through Atlas, the `shell_metadata` block will explicitly state 'User aborted the command', providing clear feedback distinct from a timeout message.

Diagnose a hanging or long-running command in Fiber with Atlas in 2026

Atlas provides Fiber developers with a precise method to diagnose whether a `go test (app.Test)` run, `go mod` operation, or any other script is genuinely slow or silently blocked on interactive input. By running commands through Atlas's `bash` tool, you receive explicit `shell_metadata` that pinpoints the exact cause, enabling you to unblock operations or adjust timeouts for your Fiber application's toolchain.

How Atlas Diagnoses Hanging Fiber Commands

In 2026, Atlas offers a robust mechanism to diagnose hanging commands in Fiber projects, leveraging its `bash` tool to race every execution against a configurable timeout. This process provides immediate feedback, often within 10 seconds, on whether a `go test ./...` run or `go mod tidy` operation is genuinely slow or silently awaiting interactive input.

When you execute a command within your Fiber project using Atlas's `bash` tool, Atlas monitors its execution time. If the command exceeds the specified timeout, Atlas terminates it and provides a detailed `shell_metadata` block in the output. This metadata is crucial for Fiber developers because it explicitly states the reason for termination. For instance, if a `go test (app.Test)` command appears to hang, the `shell_metadata` will clearly indicate if it was killed due to a timeout because it was genuinely slow, or, more commonly, if it was blocked on interactive input. This distinction is vital for debugging, as a command blocked on input will never resolve by simply waiting longer. Atlas's ability to index code by AST declarations using tree-sitter also helps it understand the context of your Fiber application, such as `app.Group` routes and `fiber.Ctx` handlers, providing a richer environment for diagnosing issues that might lead to hangs.

Concrete Fiber Commands and Files for Diagnosis

A common scenario in Fiber development involves a `go test ./...` command taking over 15 seconds, leading to uncertainty about its progress. Atlas helps pinpoint the issue by providing concrete feedback on commands like `go test (app.Test)` or `go mod tidy`, which are central to the Fiber toolchain.

To diagnose a potentially hanging command in your Fiber project, you would run it directly through Atlas's `bash` tool. For example, if your `app.Test()` suite is taking too long, you might execute `bash "go test ./..."`. Similarly, for dependency management, `bash "go mod tidy"` would be used. Atlas's `shell_metadata` output will then inform you if the `go test` command was genuinely slow, perhaps due to complex `fiber.Ctx` handler logic or extensive middleware registered before `Listen`, or if `go mod tidy` was blocked waiting for a 'yes/no' prompt. Atlas's understanding of your `go.mod` file, `app.Group` routes, and `fiber.Ctx` handlers, derived from its AST indexing, allows it to provide contextually relevant advice. This includes identifying potential issues where `fasthttp` reuses underlying buffers, requiring you to ask Atlas to copy any `ctx` value retained past the handler to prevent unexpected behavior or hangs.

Resolving Blocked or Slow Fiber Operations

If Atlas identifies a command blocked on input, such as a `go mod` prompt during a CI run, there are 2 primary ways to resolve it: either provide non-interactive flags or increase the timeout for genuinely slow operations. This ensures your Fiber development workflow remains unblocked.

Once Atlas's `shell_metadata` block diagnoses a command as blocked on interactive input, the solution is to re-run it with the appropriate non-interactive flags. For instance, a `go mod tidy` command that prompts for confirmation can be re-executed as `bash "go mod tidy -y"` to automatically accept prompts. Many Fiber-related tools, including `go test` or custom build scripts, offer similar flags like `--no-input` or a 'CI mode' to prevent interactive blocking. If, however, the diagnosis indicates a genuinely slow command, such as a large `go test (app.Test)` suite or a complex `gofmt` operation on many files, you should retry the command with a larger timeout value. Atlas's message will instruct you to do so, for example, `bash --timeout 60000 "go test ./..."` to allow 60 seconds for execution. This iterative process, guided by Atlas's explicit feedback, helps optimize your Fiber development and CI pipelines.

Atlas's Safety and Review Mechanisms for Fiber Code

Atlas prioritizes safety in 2026, ensuring every change to your Fiber application is reviewed and approved before it's written to disk. This includes modifications suggested to resolve hanging commands or optimize `gofmt` operations, providing 100% transparency and control.

When Atlas proposes changes to your Fiber codebase, perhaps to address a `fasthttp` buffer reuse issue in a `fiber.Ctx` handler or to refactor code identified during a long-running `go test`, it operates with stringent safety protocols. Every Atlas tool call is permission-gated, requiring your explicit 'allow' or 'ask' approval before execution. Before making any modifications, Atlas drafts a plan in a read-only plan agent, which you can review. If the plan involves file edits, Atlas computes a unified diff for every proposed change, surfacing it for your approval. This means you see exactly what Atlas intends to modify in your `app.Group` routes, `go.mod` file, or any other Fiber-related source before it's written. Furthermore, Atlas snapshots file changes as git patches, allowing edits to be easily diffed and rolled back if necessary. This comprehensive review process ensures that any automated fixes or optimizations for hanging commands are fully transparent and under your control, maintaining the integrity of your Fiber application.

Step by step

01Run your potentially hanging Fiber command, such as `go test ./...` or `go mod tidy`, using Atlas's `bash` tool: `bash "go test ./..."`.
02Examine the `shell_metadata` block in Atlas's output when the command is killed or completes, looking for the explicit diagnosis of 'blocked on interactive input' or 'genuinely slow'.
03If the `shell_metadata` indicates the command is blocked on interactive input (e.g., a `go mod` prompt), re-run it with the tool's non-interactive flags: `bash "go mod tidy -y"`.
04If the `shell_metadata` indicates the command is genuinely slow, retry it with a larger timeout value in milliseconds, as instructed: `bash --timeout 60000 "go test ./..."`.
05If Atlas proposes code changes to your Fiber application (e.g., to copy a `fiber.Ctx` value), review the unified diff presented by Atlas and approve it.
06After any code modifications, let Atlas run `gofmt` on the touched files to maintain code style, approving the diff if necessary.

Frequently asked questions

How does Atlas detect a hanging `go test (app.Test)` in Fiber?: Atlas detects a hanging `go test (app.Test)` by running it through its `bash` tool with a timeout. If the command exceeds this timeout, Atlas terminates it and provides `shell_metadata` that explicitly states whether the `go test` was genuinely slow or blocked on interactive input, which is crucial for Fiber test suites.
What if my `go mod tidy` command is blocked on input in a Fiber project?: If Atlas's `shell_metadata` indicates your `go mod tidy` command is blocked on input, you should re-run it using Atlas's `bash` tool with the `-y` flag: `bash "go mod tidy -y"`. This provides a non-interactive 'yes' response, allowing the `go mod` operation to complete without user intervention in your Fiber module.
Can Atlas help with `fasthttp` buffer reuse issues in Fiber handlers?: Yes, Atlas can help. Given that `fasthttp` reuses underlying buffers, if you retain a `fiber.Ctx` value past its handler, Atlas can be asked to copy that `ctx` value. This prevents unexpected behavior or hangs related to buffer reuse, leveraging Atlas's ability to read `fiber.Ctx` handlers and propose code changes.
How do I increase the timeout for a slow `gofmt` operation in Fiber?: If Atlas diagnoses a `gofmt` operation as genuinely slow, you can increase its timeout by specifying the `--timeout` flag with a larger value in milliseconds when running it via Atlas's `bash` tool. For example, `bash --timeout 30000 "gofmt -w ."` would allow 30 seconds for the formatter to complete across your Fiber project.
What safety features does Atlas offer when modifying Fiber code?: Atlas offers several safety features for Fiber code modifications: permission-gated tool calls, a read-only plan agent for drafting changes, unified diffs for every file edit requiring your approval, and git patch snapshots for easy rollback. This ensures all changes to your `app.Group` routes or `fiber.Ctx` handlers are transparent and controlled.
Does Atlas work with `go.mod` dependencies for Fiber projects?: Yes, Atlas works direct with `go.mod` dependencies. It can be run in a module whose `go.mod` requires `github.com/gofiber/fiber/v3`. Atlas can diagnose hanging `go mod` commands and, with your permission, even propose changes to your `go.mod` file or run `go mod tidy` to manage dependencies for your Fiber application.
How does Atlas distinguish a user-aborted Fiber command from a timeout?: Atlas clearly distinguishes between a user-aborted command and a timeout. If you manually interrupt a `go test` or `go mod` command running through Atlas, the `shell_metadata` block will explicitly state 'User aborted the command', providing clear feedback distinct from a timeout message.

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