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Development-only library providing x-ray vision into running Boundary applications. Zero production overhead — loaded only via the :dev and :repl-clj aliases.

Note
 Not published to Clojars. Included as a local dependency via libs/devtools.

Features

The DX Vision feature set spans six phases:

  1. Guidance Engine — startup dashboard, post-scaffold tips, contextual help, command palette

  2. Introspection — route table, config tree (secrets redacted), module/migration/test state analysis, schema exploration

  3. Error Pipeline — BND-xxx error codes, classifier → enricher → formatter chain, auto-fix suggestions

  4. Dev Dashboard — browser-based UI at localhost:9999 with live system views

  5. Advanced REPL — request/response recording, route testing, rapid prototyping

  6. Dashboard Extensions + AI — jobs monitoring, config editor, security status, AI-powered code review

Error Pipeline

Layered pipeline: classify → enrich → format → output. All pure functions in core/, side effects in shell/.

BND Error Codes

Range Category

BND-1xx

Configuration errors

BND-2xx

Validation errors

BND-3xx

Persistence errors

BND-4xx

Authentication / authorization

BND-5xx

Interceptor pipeline

BND-6xx

FC/IS violations

Auto-Fix

;; Fix the last error (safe fixes auto-apply, risky ones confirm)
(fix!)

;; Fix a specific exception
(fix! ex)

Safe fixes (e.g. setting an env var) apply automatically. Risky fixes (e.g. running a migration) always prompt for confirmation regardless of guidance level.

Dev Dashboard

Local web UI at http://localhost:9999 providing live insight into the running system.

Pages

Page What it shows

/dashboard

System overview: components, routes, modules, environment

/dashboard/routes

Filterable route table with interceptor chains

/dashboard/requests

Live request stream (HTMX polling, 2s interval)

/dashboard/schemas

Malli schema browser with example generation

/dashboard/db

Database explorer: migrations, pool stats, query runner

/dashboard/errors

BND-coded errors with fix suggestions

/dashboard/jobs

Job queue stats, failed jobs with retry button

/dashboard/config

Editable config tree with secret redaction and diff preview

/dashboard/security

Security posture: password policy, auth methods, MFA, CSRF, rate limiting

/dashboard/docs

In-app documentation browser

Architecture

  • Integrant component (:boundary/dashboard) starts Jetty on port 9999

  • Server-rendered Hiccup + HTMX polling for live updates

  • Request capture middleware wraps the main HTTP handler (port 3000)

  • Dark theme CSS in resources/dashboard/assets/dashboard.css

Introspection & REPL Tools

;; Route table
(routes)

;; Config tree (secrets redacted)
(config)

;; Module summary
(modules)

;; Schema exploration
(schema-tree :user/CreateUser)
(schema-example :user/CreateUser)
(schema-diff :user/CreateUser :user/UpdateUser)

Request Recording

Capture HTTP request/response pairs for debugging and replay.

;; Start recording
(def session (recording/create-session))

;; After capturing entries, inspect them
(recording/format-entry-table session)
(recording/diff-entries session 0 1)

;; Save/load sessions
(recording/serialize-session session)

Route Testing

Add or remove routes on a running system without restart.

;; Add a temporary test route
(router/add-route {:path "/test" :method :get :handler my-handler})

;; Inject a tap interceptor for debugging
(router/inject-tap-interceptor route-name)

AI REPL Commands

Three AI-powered commands (require an AI provider to be configured):

;; Code review
(ai/review "path/to/file.clj")

;; Suggest missing test cases
(ai/test-ideas "path/to/file.clj")

;; FC/IS refactoring guide
(ai/refactor-fcis 'boundary.product.core.validation)

(new-feature!) Workflow

End-to-end feature scaffolding from a single REPL call:

(new-feature! "invoicing"
  "Invoice module with customer, line-items, PDF export")

Steps: AI spec generation → confirm → scaffold → integrate → test.

Key namespaces

Namespace Layer Responsibility

boundary.devtools.core.error_classifier

core

Exception → BND-xxx code mapping (5 strategies)

boundary.devtools.core.error_enricher

core

Adds stacktrace, suggestions, fix descriptor, URLs

boundary.devtools.core.error_formatter

core

Rich formatted output with BND code header

boundary.devtools.core.auto_fix

core

Pure fix descriptor registry

boundary.devtools.core.error_codes

core

BND error catalog (BND-1xx through BND-6xx)

boundary.devtools.core.guidance

core

Startup dashboard, tips, command palette

boundary.devtools.core.introspection

core

Route table, config tree, module summary

boundary.devtools.core.schema_tools

core

Schema tree, diff, example generation

boundary.devtools.core.recording

core

Request/response session management

boundary.devtools.core.router

core

Route addition/removal, tap interceptor injection

boundary.devtools.core.prototype

core

Malli schema → scaffold spec conversion

boundary.devtools.core.config_editor

core

Config redaction, formatting, diff

boundary.devtools.core.security_analyzer

core

Security posture analysis

boundary.devtools.shell.repl

shell

Unified REPL API

boundary.devtools.shell.dashboard.server

shell

Integrant component, Reitit router for dashboard

boundary.devtools.shell.http_error_middleware

shell

Dev error enrichment middleware

Testing

clojure -M:test:db/h2 :devtools