# Audit a Deno Repository with Parallel Subagents in Atlas, 2026

> Atlas enables Deno developers to audit large repositories efficiently by fanning out work to parallel subagents, preserving the main session's context window.

In 2026, Deno developers can sweep an entire repository for specific problems without overwhelming the main session's context window by leveraging Atlas's parallel subagents. This approach integrates direct with Deno's built-in toolchain, including deno test, deno fmt, and deno add (JSR), ensuring a familiar and efficient auditing experience.

## Key takeaways

- Atlas uses parallel subagents to audit Deno repos without context window limits.
- The explore subagent provides a read-only, deny-by-default audit for Deno projects.
- Atlas integrates directly with Deno's deno.json and native tools like deno test and deno fmt.
- Deno's permission flags align with Atlas's permission-gated tool calls for secure operations.
- Audit findings from multiple subagents are consolidated into an atlas todowrite list for remediation.
- Atlas provides unified diffs and approval prompts for all changes made to Deno files.

## How do I audit a Deno repository without blowing my context window?

Auditing a large Deno repository in 2026 for a specific class of problem no longer requires sacrificing your main session's context window. Atlas addresses this by fanning out work to multiple subagents, each operating in its own isolated session, ensuring that only their concise conclusions return to your primary context.

Atlas's task tool is central to this strategy, allowing you to launch multiple subagents concurrently. For a read-only sweep, the explore subagent type is ideal, as it is deny-by-default and cannot make changes, providing a safe environment for auditing. This is particularly well-suited for Deno projects, where Atlas can read your deno.json or deno.jsonc configuration, understand JSR and npm specifiers, and interpret defined tasks. By splitting the audit into independent slices,perhaps by directory, Deno module, or specific rule,you can assign each slice to a dedicated subagent. For instance, one subagent might grep for deprecated API usage in src/utils/, while another globs for unformatted files in src/components/, all without their intermediate file dumps ever entering your main context window. Only their final, summarized findings are reported back, making large-scale repository sweeps manageable and efficient.

## How does Atlas integrate with Deno's built-in tools and permissions?

Atlas deeply integrates with Deno's batteries-included toolchain and robust permission model, making it a natural fit for Deno developers in 2026. Every Atlas tool call is permission-gated, mirroring Deno's own --allow-net or --allow-read flags, ensuring secure and controlled operations within your deno.json configured project.

Atlas is designed to understand and leverage the Deno ecosystem. When running Atlas in a Deno project, it automatically reads your deno.json or deno.jsonc file, parsing import maps, JSR and npm specifiers, and any defined tasks. This allows Atlas to intelligently interact with your codebase using Deno's native commands. For example, Atlas can be instructed to run deno test to validate code, deno check for type-checking, or deno fmt and deno lint to ensure code style consistency. Crucially, Atlas's permission-gating system aligns perfectly with Deno's. Before any command runs, Atlas presents a prompt, allowing you to approve or deny specific actions, much like Deno's own runtime permissions. This means you can ask Atlas to tighten a broad --allow-all task down to the specific --allow-net and --allow-read scopes that your Deno code truly requires, enhancing security and control during an audit or development task. Atlas can even assist in managing dependencies by suggesting deno add jsr:@std/... rather than requiring manual import_map.json edits.

## What are the safety features for auditing Deno code with Atlas?

Ensuring safety during a repository audit is paramount, especially when dealing with a large Deno codebase in 2026. Atlas provides robust safety mechanisms, primarily through its explore subagent type, which is explicitly deny-by-default and read-only, preventing any unintended modifications to your project files.

The explore subagent is specifically designed for tasks like repository audits where no changes should be made. When you launch a task with subagent_type explore, the subagent operates under a strict read-only policy. This means it can search code with hybrid semantic and keyword retrieval, index code by AST declarations using tree-sitter, and even build its code index with local Ollama embeddings, all without the ability to write to disk. This deny-by-default nature provides a strong guarantee against accidental edits. For scenarios where a subagent might need to run Deno commands for analysis (e.g., deno check on a specific file), the general subagent type can be used, but even then, every tool call is permission-gated. Furthermore, Atlas drafts a plan in a read-only plan agent and asks for approval before switching to a build agent, and computes a unified diff for every file edit, surfacing it for approval before writing. This multi-layered approach ensures that you, the Deno developer, maintain full control over any potential changes, even when fanning out work to multiple parallel subagents.

## How do I collect and fix audit findings from parallel Deno subagents?

After parallel subagents complete their audit slices across your Deno repository, collecting and acting on their findings is a streamlined process in 2026. Atlas automatically surfaces each subagent's final message, allowing you to merge these conclusions into a unified todowrite list for efficient remediation within your main session.

Once you issue multiple task calls concurrently, Atlas manages the execution of each subagent. Upon completion, Atlas collects each subagent's final message. If a subagent encounters an issue or fails, its error text is surfaced verbatim; if it was cancelled, 'Task cancelled' is reported. This clear feedback mechanism allows you to quickly assess the outcome of each audit slice. The next step is to merge these individual findings into a single, actionable todowrite list. This list serves as a consolidated view of all identified problems across your Deno project. From this todowrite list, you can then use the edit tool in your main Atlas session to address each issue. Atlas assists in this remediation by computing a unified diff for every file edit and surfacing it for approval before writing, and can even snapshot file changes as git patches so edits can be diffed and rolled back. This ensures that fixes are applied precisely and with full transparency, maintaining the integrity of your Deno codebase.

## Steps

1. Split your Deno repository audit into independent slices: Divide the codebase by directory (e.g., src/api/, src/components/), Deno module, or specific rule to ensure subagents do not overlap.
2. Launch parallel read-only explore subagent tasks: Issue multiple atlas task --subagent-type explore "Audit src/api/ for deprecated Deno.serve usage" calls concurrently to sweep each slice without making changes.
3. Collect final messages from each Deno subagent: Monitor Atlas as it surfaces each subagent's conclusion, including any verbatim error text or 'Task cancelled' messages.
4. Merge findings into a todowrite list: Consolidate the individual subagent reports into a single atlas todowrite list to create an actionable plan for your Deno project.
5. Fix identified issues in the main session with edit: Use atlas edit to address problems, leveraging Atlas's unified diffs and approval prompts before writing changes to your Deno files.
6. Run deno fmt and deno lint on the diff: After edits, ask Atlas to run deno fmt and deno lint on the modified files to ensure Deno's code style and quality standards are maintained.
7. Validate changes with deno test and deno check: Have Atlas execute deno test and deno check behind a permission prompt to confirm that fixes haven't introduced regressions in your Deno application.

## FAQ

### How do Atlas subagents handle Deno's deno.json configuration?

Atlas automatically reads your deno.json or deno.jsonc file when operating within a Deno project. This allows it to understand your import maps, JSR and npm specifiers, and any tasks defined in the configuration, ensuring subagents operate with full awareness of your Deno project's setup.

### Can Atlas subagents run Deno commands like deno test or deno fmt?

Yes, Atlas subagents can run Deno commands. For read-only analysis, the explore subagent is preferred. If a subagent needs to execute commands like deno test, deno check, deno fmt, or deno lint, you would use the general subagent type. Every command execution is permission-gated by Atlas, requiring your approval.

### How does Atlas prevent subagents from making unwanted changes to my Deno code?

Atlas employs several safety measures. The explore subagent type is deny-by-default and strictly read-only, preventing any file modifications. For general subagents, Atlas drafts a plan in a read-only agent, asks for approval, and computes a unified diff for every proposed file edit, which you must approve before writing.

### What is the benefit of using parallel subagents for a Deno repository audit?

The primary benefit is sweeping an entire Deno repository for problems without blowing the main session's context window. By fanning out work to parallel subagents, each handles a slice of the audit, and only their concise conclusions return, making large-scale audits efficient and manageable.

### How does Atlas manage Deno dependencies with JSR?

Atlas understands JSR specifiers and can assist in managing Deno dependencies. It can suggest or execute deno add jsr:@std/... commands to add new dependencies, automatically updating your import map without requiring manual edits, streamlining dependency management in your Deno project.

### Can Atlas help tighten Deno's permission flags for tasks?

Yes, Atlas can help tighten Deno's permission flags. If a task is initially defined with a broad --allow-all, you can ask Atlas to analyze the code and suggest narrowing the scope to specific permissions, such as --allow-net or --allow-read, aligning with Deno's granular security model.

### How do I review the changes proposed by Atlas after an audit?

After an audit and subsequent remediation using atlas edit, Atlas computes a unified diff for every file edit. This diff is surfaced for your approval before any changes are written to your Deno files. Atlas also snapshots file changes as git patches, allowing you to easily diff and roll back edits if needed.

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