diff --git a/.gitignore b/.gitignore
index f431220..f3de3cf 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,5 @@ test_input.txt
 
 # Generated artifacts (source of truth is .org)
 /skills/*.lisp
-/tests/*.lisp
 /tmp/*.lisp
 *.fasl
diff --git a/lisp/core-skills.lisp b/lisp/core-skills.lisp
index 97c7363..7b839b3 100644
--- a/lisp/core-skills.lisp
+++ b/lisp/core-skills.lisp
@@ -99,11 +99,8 @@
                                     (string= n "security-dispatcher")
                                     (string= n "system-model-router")
                                     (string= n "system-model-embedding")
-                                     (string= n "system-model-explorer")
-                                     (string= n "gateway-tui")
-                                     (string= n "gateway-tui-model")
-                                     (string= n "gateway-tui-view")
-                                     (string= n "gateway-tui-main"))))
+                                    (string= n "system-model-explorer")
+                                    (string= n "gateway-tui"))))
                            all-files))
         (adj (make-hash-table :test 'equal))
         (name-to-file (make-hash-table :test 'equal))
@@ -284,3 +281,29 @@
             (load-skill-from-lisp file)
             (load-skill-from-org file)))
       (log-message "LOADER: Boot Complete."))))
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (ql:quickload :fiveam :silent t))
+
+(defpackage :passepartout-boot-tests
+  (:use :cl :fiveam :passepartout)
+  (:export #:boot-suite))
+
+(in-package :passepartout-boot-tests)
+
+(def-suite boot-suite :description "Verification of the Skill Engine loader")
+(in-suite boot-suite)
+
+(test test-topological-sort-basic
+  (let ((tmp-dir "/tmp/passepartout-boot-test/"))
+    (uiop:ensure-all-directories-exist (list tmp-dir))
+    (with-open-file (out (merge-pathnames "org-skill-a.org" tmp-dir) :direction :output :if-exists :supersede)
+      (format out "#+DEPENDS_ON: skill-b-id~%"))
+    (with-open-file (out (merge-pathnames "org-skill-b.org" tmp-dir) :direction :output :if-exists :supersede)
+      (format out ":PROPERTIES:~%:ID: skill-b-id~%:END:~%"))
+    (unwind-protect
+         (let ((sorted (passepartout::skill-topological-sort tmp-dir)))
+           (let ((pos-a (position "org-skill-a" sorted :key #'pathname-name :test #'string-equal))
+                 (pos-b (position "org-skill-b" sorted :key #'pathname-name :test #'string-equal)))
+             (is (< pos-b pos-a))))
+       (uiop:delete-directory-tree (uiop:ensure-directory-pathname tmp-dir) :validate t))))
diff --git a/lisp/gateway-tui-main.lisp b/lisp/gateway-tui-main.lisp
index 9b1d5b8..f7824e2 100644
--- a/lisp/gateway-tui-main.lisp
+++ b/lisp/gateway-tui-main.lisp
@@ -163,3 +163,24 @@
         (refresh scr)
         (sleep 0.03))
        (disconnect-daemon))))
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (ql:quickload :fiveam :silent t))
+
+(defpackage :passepartout-tui-tests
+  (:use :cl :passepartout)
+  (:export #:tui-suite))
+
+(in-package :passepartout-tui-tests)
+
+(fiveam:def-suite tui-suite :description "Verification of the TUI parsing and styling logic")
+(fiveam:in-suite tui-suite)
+
+(fiveam:test test-tui-connection-drop
+  "Tier 2 Chaos: Verify that handle-return degrades gracefully when the daemon connection is lost."
+  (let ((passepartout.gateway-tui::*incoming-msgs* nil)
+        (passepartout.gateway-tui::*input-buffer* (make-array 5 :element-type 'character :initial-contents "hello" :fill-pointer 5 :adjustable t))
+        (mock-stream (make-string-output-stream)))
+    (close mock-stream)
+    (passepartout.gateway-tui::handle-return mock-stream)
+    (fiveam:is (member "ERROR: Connection to daemon lost." passepartout.gateway-tui::*incoming-msgs* :test #'string=))))
diff --git a/lisp/programming-lisp.lisp b/lisp/programming-lisp.lisp
index 933a126..a64600e 100644
--- a/lisp/programming-lisp.lisp
+++ b/lisp/programming-lisp.lisp
@@ -1,3 +1,5 @@
+(in-package :passepartout)
+
 (defun lisp-structural-check (code)
   "Checks if parentheses are balanced and the code is readable."
   (handler-case
@@ -146,3 +148,78 @@
 (defskill :passepartout-programming-lisp
   :priority 400
   :trigger (lambda (ctx) (declare (ignore ctx)) nil))
+
+(defpackage :passepartout-utils-lisp-tests
+  (:use :cl :fiveam :passepartout)
+  (:export #:utils-lisp-suite))
+
+(in-package :passepartout-utils-lisp-tests)
+
+(def-suite utils-lisp-suite
+  :description "Tests for the Lisp Validator structural, syntactic, and semantic gates")
+
+(in-suite utils-lisp-suite)
+
+(test structural-balanced
+  (is (eq t (passepartout:lisp-structural-check "(+ 1 2)"))))
+
+(test structural-unbalanced-open
+  (multiple-value-bind (ok reason) (passepartout:lisp-structural-check "(+ 1 2")
+    (is (null ok))
+    (is (search "Reader Error" reason))))
+
+(test structural-unbalanced-close
+  (multiple-value-bind (ok reason) (passepartout:lisp-structural-check "+ 1 2)")
+    (is (null ok))
+    (is (search "Reader Error" reason))))
+
+(test syntactic-valid
+  (is (eq t (passepartout:lisp-syntactic-check "(+ 1 2)"))))
+
+(test semantic-safe
+  (is (eq t (passepartout:lisp-semantic-check "(+ 1 2)"))))
+
+(test semantic-blocked-eval
+  (multiple-value-bind (ok reason) (passepartout:lisp-semantic-check "(eval '(+ 1 2))")
+    (is (null ok))
+    (is (search "Unsafe" reason))))
+
+(test unified-success
+  (let ((result (passepartout:lisp-validate "(+ 1 2)" :strict t)))
+    (is (eq (getf result :status) :success))))
+
+(test unified-failure
+  (let ((result (passepartout:lisp-validate "(+ 1 2" :strict nil)))
+    (is (eq (getf result :status) :error))))
+
+(test eval-basic
+  (let ((result (passepartout:lisp-eval "(+ 1 2)")))
+    (is (eq (getf result :status) :success))
+    (is (string= (getf result :result) "3"))))
+
+(test structural-extract
+  (let* ((code "(defun hello () (print \"hi\")) (defun bye () (print \"bye\"))")
+         (extracted (passepartout:lisp-extract code "hello")))
+    (is (not (null extracted)))
+    (let ((form (read-from-string extracted)))
+      (is (eq (car form) 'DEFUN))
+      (is (eq (second form) 'HELLO)))))
+
+(test list-definitions
+  (let ((code "(defun foo () t) (defmacro bar () nil) (defparameter *baz* 10)"))
+    (let ((names (passepartout:lisp-list-definitions code)))
+      (is (member 'FOO names))
+      (is (member 'BAR names))
+      (is (member '*BAZ* names)))))
+
+(test structural-inject
+  (let* ((code "(defun my-fun (x) (print x))")
+         (injected (passepartout:lisp-inject code "my-fun" "(finish-output)")))
+    (let ((form (read-from-string injected)))
+      (is (equal (last form) '((FINISH-OUTPUT)))))))
+
+(test structural-slurp
+  (let* ((code "(defun work () (step-1))")
+         (slurped (passepartout:lisp-slurp code "work" "(step-2)")))
+    (let ((form (read-from-string slurped)))
+      (is (equal (last form) '((STEP-2)))))))
diff --git a/lisp/programming-org.lisp b/lisp/programming-org.lisp
index 8575f5c..c423d54 100644
--- a/lisp/programming-org.lisp
+++ b/lisp/programming-org.lisp
@@ -1,3 +1,5 @@
+(in-package :passepartout)
+
 (defun org-filetags-extract (content)
   "Extracts the list of tags from a #+FILETAGS: line."
   (let ((lines (uiop:split-string content :separator '(#\Newline))))
@@ -242,3 +244,41 @@ AST format: (:TYPE :HEADLINE :properties (:ID ... :TITLE ... :TAGS (...))
 (defskill :passepartout-programming-org
   :priority 100
   :trigger (lambda (ctx) (declare (ignore ctx)) nil))
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (ignore-errors (ql:quickload :fiveam :silent t)))
+
+(defpackage :passepartout-utils-org-tests
+  (:use :cl :fiveam :passepartout)
+  (:export #:utils-org-suite))
+
+(in-package :passepartout-utils-org-tests)
+
+(def-suite utils-org-suite
+  :description "Tests for Utils Org skill.")
+
+(in-suite utils-org-suite)
+
+(test id-generation
+  (let ((id1 (org-id-generate))
+        (id2 (org-id-generate)))
+    (is (plusp (length id1)))
+    (is (not (string= id1 id2)))))
+
+(test id-format
+  (let ((formatted (org-id-format "abc12345")))
+    (is (search "id:" formatted))))
+
+(test property-setter
+  (let ((ast (list :type :HEADLINE
+                  :properties (list :ID "id:test123" :TITLE "Test")
+                  :contents nil)))
+    (org-property-set ast "id:test123" :STATUS "ACTIVE")
+    (is (string= (getf (getf ast :properties) :STATUS) "ACTIVE"))))
+
+(test todo-setter
+  (let ((ast (list :type :HEADLINE
+                  :properties (list :ID "id:todo001" :TITLE "Task")
+                  :contents nil)))
+    (org-todo-set ast "id:todo001" "DONE")
+    (is (string= (getf (getf ast :properties) :TODO) "DONE"))))
diff --git a/lisp/system-diagnostics.lisp b/lisp/system-diagnostics.lisp
index adfdf69..de7b4ff 100644
--- a/lisp/system-diagnostics.lisp
+++ b/lisp/system-diagnostics.lisp
@@ -172,6 +172,34 @@
       (uiop:quit 0)
       (uiop:quit 1)))
 
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (ql:quickload :fiveam :silent t))
+
+(defpackage :passepartout-diagnostics-tests
+  (:use :cl :fiveam :passepartout)
+  (:export #:diagnostics-suite))
+
+(in-package :passepartout-diagnostics-tests)
+
+(def-suite diagnostics-suite :description "Verification of the System Diagnostics logic")
+(in-suite diagnostics-suite)
+
+(test test-diagnostics-dependency-fail
+  "Verify that missing binaries are correctly identified as failures."
+  (let ((passepartout::*diagnostics-binaries* '("non-existent-binary-123")))
+    (is (null (diagnostics-dependencies-check)))))
+
+(test test-diagnostics-env-fail
+  "Verify that an invalid MEMEX_DIR triggers a critical failure."
+  (let ((old-m (uiop:getenv "MEMEX_DIR"))
+        (old-d (uiop:getenv "PASSEPARTOUT_DATA_DIR")))
+    (unwind-protect
+         (progn
+           (setf (uiop:getenv "MEMEX_DIR") "/non/existent/path/999")
+           (is (null (diagnostics-env-check))))
+      (setf (uiop:getenv "MEMEX_DIR") (or old-m ""))
+      (setf (uiop:getenv "PASSEPARTOUT_DATA_DIR") (or old-d "")))))
+
 (defskill :passepartout-system-diagnostics
   :priority 100
   :trigger (lambda (ctx) (eq (getf (getf ctx :payload) :sensor) :heartbeat))
diff --git a/lisp/system-model-explorer.lisp b/lisp/system-model-explorer.lisp
index a33432f..b3df95e 100644
--- a/lisp/system-model-explorer.lisp
+++ b/lisp/system-model-explorer.lisp
@@ -67,3 +67,43 @@
     (:chat . "Casual conversation, Q&A, creative writing. Prefer balanced quality, low latency.\nRecommend: Llama 3.3 70B (strong generalist) or Gemma 4 31B (thinking mode).")
     (:plan . "Strategic planning, architecture design, complex multi-step reasoning.\nRecommend: Owl Alpha (free, tool use, 1M ctx) or Hermes 3 405B (strongest free reasoning).")
     (:background . "Heartbeat summaries, delegation responses, tool output filtering. Must be small + fast.\nRecommend: Llama 3.2 3B (131K ctx, fast) or LFM 2.5 1.2B (edge-ready).")))
+
+;; REPL-verified: 2026-05-04
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (ignore-errors (ql:quickload :fiveam :silent t)))
+
+(defpackage :passepartout-system-model-explorer-tests
+  (:use :cl :passepartout)
+  (:export #:model-explorer-suite))
+
+(in-package :passepartout-system-model-explorer-tests)
+
+(fiveam:def-suite model-explorer-suite :description "Tests for the model explorer skill")
+
+(fiveam:in-suite model-explorer-suite)
+
+(fiveam:test model-explorer-recommend-slots
+  "model-explorer-recommend should return models for all standard slots"
+  (dolist (slot '(:code :chat :plan :background))
+    (let ((recs (passepartout::model-explorer-recommend slot)))
+      (fiveam:is (listp recs))
+      (fiveam:is (>= (length recs) 1)))))
+
+(fiveam:test model-explorer-recommend-format
+  "Each recommendation should have :id and :name"
+  (dolist (rec (passepartout::model-explorer-recommend :chat))
+    (fiveam:is (getf rec :id))
+    (fiveam:is (getf rec :name))))
+
+(fiveam:test model-explorer-recommend-unknown-slot
+  "Unknown slot should return fallback"
+  (let ((recs (passepartout::model-explorer-recommend :unknown)))
+    (fiveam:is (listp recs))
+    (fiveam:is (>= (length recs) 1))))
+
+(fiveam:test model-explorer-fetch-openrouter-count
+  "OpenRouter API should return at least 300 models"
+  (let ((models (passepartout::model-explorer-fetch :openrouter)))
+    (if models
+        (fiveam:is (>= (length models) 300))
+        (fiveam:skip "API unreachable"))))
diff --git a/lisp/system-model-provider.lisp b/lisp/system-model-provider.lisp
index 484f76c..4854ac6 100644
--- a/lisp/system-model-provider.lisp
+++ b/lisp/system-model-provider.lisp
@@ -116,3 +116,20 @@ If API-KEY is nil, reads from environment."
 (defskill :passepartout-system-model-provider
   :priority 50
   :trigger (lambda (ctx) (declare (ignore ctx)) nil))
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (ql:quickload :fiveam :silent t))
+
+(defpackage :passepartout-llm-gateway-tests
+  (:use :cl :passepartout)
+  (:export #:llm-gateway-suite))
+
+(in-package :passepartout-llm-gateway-tests)
+
+(fiveam:def-suite llm-gateway-suite :description "Tests for the LLM provider backend")
+(fiveam:in-suite llm-gateway-suite)
+
+(fiveam:test test-provider-rejects-bad-keyword
+  "Verify that provider-openai-request returns :error for an unregistered provider."
+  (let ((result (provider-openai-request "hello" "test" :provider :not-a-real-provider)))
+    (fiveam:is (eq (getf result :status) :error))))
diff --git a/org/core-manifest.org b/org/core-manifest.org
index 497f1b0..98b3222 100644
--- a/org/core-manifest.org
+++ b/org/core-manifest.org
@@ -40,21 +40,7 @@ Components are loaded in sequence (~:serial t~): package first (defines the publ
 
 ** Test System
 
-The test system loads on top of ~opencortex~ and adds FiveAM (the test framework). Each test file is tangled from a ~:tangle ../tests/...~ block in the parent org file.
-
-Note: not every harness or skill file has a corresponding test file. Tests exist only for the parts of the system where deterministic verification is most critical — the pipeline stages, the loader, the memory Merkle tree, and the peripheral vision model.
-
-#+begin_src lisp
-(defsystem :passepartout/tests
-  :depends-on (:passepartout :fiveam)
-  :components ((:file "tests/programming-org-tests")
-               (:file "tests/programming-lisp-tests")
-               (:file "tests/boot-sequence-tests")
-               (:file "tests/model-explorer-tests")
-               (:file "tests/diagnostics-tests")
-               (:file "tests/tui-tests")
-               (:file "tests/llm-gateway-tests")))
-#+end_src
+Tests are embedded directly in each module's source file — see the `* Test Suite` section at the end of each `.org` file. No separate test system is needed.
 
 ** TUI System
 
diff --git a/org/core-skills.org b/org/core-skills.org
index c7f5a2c..870d4a6 100644
--- a/org/core-skills.org
+++ b/org/core-skills.org
@@ -411,7 +411,7 @@ files live after tangling. The org source files live in ~org/~.
 
 * Test Suite
 Verifies that the topological sorter correctly orders skills by their ~#+DEPENDS_ON:~ declarations.
-#+begin_src lisp :tangle ../tests/boot-sequence-tests.lisp
+#+begin_src lisp
 (eval-when (:compile-toplevel :load-toplevel :execute)
   (ql:quickload :fiveam :silent t))
 
diff --git a/org/gateway-tui-main.org b/org/gateway-tui-main.org
index ef59b1c..228c8e1 100644
--- a/org/gateway-tui-main.org
+++ b/org/gateway-tui-main.org
@@ -185,7 +185,7 @@ Event handlers + daemon I/O + main loop.
 #+end_src
 
 * Test Suite
-#+begin_src lisp :tangle ../tests/tui-tests.lisp
+#+begin_src lisp
 (eval-when (:compile-toplevel :load-toplevel :execute)
   (ql:quickload :fiveam :silent t))
 
diff --git a/org/programming-lisp.org b/org/programming-lisp.org
index e9ab9bd..68d21d6 100644
--- a/org/programming-lisp.org
+++ b/org/programming-lisp.org
@@ -17,6 +17,11 @@ The skill has four layers:
 
 * Implementation
 
+** Package Context
+#+begin_src lisp
+(in-package :passepartout)
+#+end_src
+
 ** Structural Validation
 ;; REPL-VERIFIED: 2026-05-03T13:00:00
 #+begin_src lisp
@@ -215,7 +220,7 @@ The skill has four layers:
 
 * Test Suite
 Tests for the Lisp Validator structural, syntactic, and semantic gates.
-#+begin_src lisp :tangle ../tests/programming-lisp-tests.lisp
+#+begin_src lisp
 (defpackage :passepartout-utils-lisp-tests
   (:use :cl :fiveam :passepartout)
   (:export #:utils-lisp-suite))
diff --git a/org/programming-org.org b/org/programming-org.org
index 3087357..4a3a34b 100644
--- a/org/programming-org.org
+++ b/org/programming-org.org
@@ -8,6 +8,11 @@ Structural manipulation tools for Org-mode files. This skill handles reading, wr
 
 * Implementation
 
+** Package Context
+#+begin_src lisp
+(in-package :passepartout)
+#+end_src
+
 ** Reading Files (with Privacy Filter)
 ;; REPL-VERIFIED: 2026-05-03T13:00:00
 #+begin_src lisp
@@ -331,7 +336,7 @@ AST format: (:TYPE :HEADLINE :properties (:ID ... :TITLE ... :TAGS (...))
 
 * Test Suite
 Verification of the structural manipulation for Org-mode files and their AST representation.
-#+begin_src lisp :tangle ../tests/programming-org-tests.lisp
+#+begin_src lisp
 (eval-when (:compile-toplevel :load-toplevel :execute)
   (ignore-errors (ql:quickload :fiveam :silent t)))
 
diff --git a/org/system-diagnostics.org b/org/system-diagnostics.org
index d2ccf03..0e10196 100644
--- a/org/system-diagnostics.org
+++ b/org/system-diagnostics.org
@@ -243,7 +243,7 @@ The doctor checks all supported LLM providers and detects local Ollama instances
 
 * Phase D: Verification (Testing)
 
-#+begin_src lisp :tangle ../tests/diagnostics-tests.lisp
+#+begin_src lisp
 (eval-when (:compile-toplevel :load-toplevel :execute)
   (ql:quickload :fiveam :silent t))
 
diff --git a/org/system-model-explorer.org b/org/system-model-explorer.org
index ae37ace..35027c4 100644
--- a/org/system-model-explorer.org
+++ b/org/system-model-explorer.org
@@ -104,7 +104,7 @@ Recommended models are curated per task slot — code generation needs different
 
 * Tests
 
-#+begin_src lisp :tangle ../tests/model-explorer-tests.lisp
+#+begin_src lisp
 ;; REPL-verified: 2026-05-04
 (eval-when (:compile-toplevel :load-toplevel :execute)
   (ignore-errors (ql:quickload :fiveam :silent t)))
diff --git a/org/system-model-provider.org b/org/system-model-provider.org
index 57212fa..5f1d4b9 100644
--- a/org/system-model-provider.org
+++ b/org/system-model-provider.org
@@ -163,7 +163,7 @@ If API-KEY is nil, reads from environment."
 #+end_src
 
 * Test Suite
-#+begin_src lisp :tangle ../tests/llm-gateway-tests.lisp
+#+begin_src lisp
 (eval-when (:compile-toplevel :load-toplevel :execute)
   (ql:quickload :fiveam :silent t))
 
diff --git a/passepartout.asd b/passepartout.asd
index 6638e5c..4bacbca 100644
--- a/passepartout.asd
+++ b/passepartout.asd
@@ -16,16 +16,6 @@
                (:file "lisp/core-loop-act")
                (:file "lisp/core-loop")))
 
-(defsystem :passepartout/tests
-  :depends-on (:passepartout :fiveam)
-  :components ((:file "tests/programming-org-tests")
-               (:file "tests/programming-lisp-tests")
-               (:file "tests/boot-sequence-tests")
-               (:file "tests/model-explorer-tests")
-               (:file "tests/diagnostics-tests")
-               (:file "tests/tui-tests")
-               (:file "tests/llm-gateway-tests")))
-
 (defsystem :passepartout/tui
   :depends-on (:passepartout :croatoan :usocket :bordeaux-threads)
   :components ((:file "lisp/gateway-tui")))