diff --git a/docs/commands.md b/docs/commands.md
index 554ae783..0435f396 100644
--- a/docs/commands.md
+++ b/docs/commands.md
@@ -121,6 +121,40 @@ never `--stand-alone` or `--exclude-root`; `--exclude-dependency` and
 out. The selected environment's `exclude-services` also removes services from
 the composition roots; a module withdrawn whole contributes no root, including
 its service-entry. CLI and run-profile exclusions still apply on top.
+
+**An operation is held to the environment it selected, never refused because a
+DIFFERENT environment's `exclude-services` is inconsistent with the workspace
+graph.** Run, build, deploy and `deploy gitops render` each check the one
+environment they were given against the graph, and a refusal names that
+environment in the message itself rather than only under `--debug`.
+
+This is scoped to the graph-consistency check, which is where the
+cross-environment refusal came from. It is not a general rule that other
+environments are ignored. The check itself decodes and validates EVERY
+environment's declarations before it compares the selected one against the
+graph, so a **malformed** `exclude-services` anywhere — an unqualified name, a
+duplicate, a service withdrawn from itself — still refuses, whatever was
+selected. (Loading the workspace does not: a workspace with such a declaration
+still loads, and a clean environment still selects. It is the validation that
+refuses, not the load.) Module namespaces, host composition,
+service-scoped names (`service-config`, `service-identity`, `service-mesh`)
+and `managed-services` keys are likewise still held across every environment,
+so a bad declaration in one of those blocks in an unselected environment can
+still refuse a correct operation elsewhere.
+This matters because the exclusion graph is the workspace's **current**
+composition: an environment imported before a module overlay added a service
+carries no `withdrawn-from` for it, so holding every environment to that graph
+refused a correct render of a different environment — and the operator could
+not satisfy it, since re-importing the offending environment requires the
+product intent to declare it.
+
+Every CLI path that checks exclusions against the graph selects an
+environment: run, build, test and deploy through the flow, `deploy gitops
+render` and the solution and dev renders through the workspace validation, and
+`codefly doctor workspace` through its own scope check — doctor selects and
+calls the selected check directly, rather than relying on the fallback. The
+whole-workspace form, which holds every environment's graph at once, remains
+the behaviour for a caller that has selected none.
 The deterministic port hash folds every endpoint into a few thousand
 buckets, so a `--naming-scope` can hash two endpoints to one port and abort
 the run; `--temporary-ports` sidesteps the hash, under the ordering its
diff --git a/docs/configuration-contract.md b/docs/configuration-contract.md
index d37a17dd..b90b8194 100644
--- a/docs/configuration-contract.md
+++ b/docs/configuration-contract.md
@@ -243,7 +243,19 @@ environments:
 Nothing may still reach what is withdrawn: a service that declares a
 dependency on it is refused unless `withdrawn-from` names it, and so are a
 solution consuming one of its endpoints, an environment declaration naming it
-and a configuration reference to one of its endpoints. A service the module's
+and a configuration reference to one of its endpoints. **Those refusals are
+judged for the environment the operation selected, and the message names that
+environment**: an operation is not refused because a different environment's
+`exclude-services` is inconsistent with the workspace graph. A **malformed**
+exclusion is a separate matter — the check validates every environment's
+declarations for shape before comparing the selected one against the graph, so
+one of those refuses whatever was selected. It is the validation that refuses,
+not the load: such a workspace still loads, and a clean environment still
+selects. That distinction is load-bearing, because the graph a
+declaration is held to is the workspace's current composition — an environment
+imported before a module overlay added a service carries no `withdrawn-from`
+for it, and holding every environment to that graph refuses operations on
+environments whose own declarations are complete. A service the module's
 `interface:` exports, or names its `service-entry`, is withdrawn only with the
 whole module: an environment that names every service of a module leaves the
 module out, and its exports leave with it. Withdrawing some of its services is
diff --git a/pkg/environments/excluded_services.go b/pkg/environments/excluded_services.go
index 87c0a744..6ae0ccb1 100644
--- a/pkg/environments/excluded_services.go
+++ b/pkg/environments/excluded_services.go
@@ -161,10 +161,12 @@ func ValidateEnvironmentExclusions(ctx context.Context, workspace *resources.Wor
 	if err != nil {
 		return err
 	}
-	if err := env.validateExclusionsAgainst(graph); err != nil {
-		return fmt.Errorf("environment %q: %w", env.Name, err)
-	}
-	return nil
+	// No "environment %q:" prefix here: validateExclusionsAgainst names the
+	// environment inside each message, because a prefix is a separate link in
+	// the error chain and the plain renderer shows only the leaf — which is how
+	// a `--env blue` refusal printed no environment at all and sent its reader
+	// to re-declare something that was already declared.
+	return env.validateExclusionsAgainst(graph)
 }
 
 // ValidateExcludedServices holds every environment's exclude-services to the
@@ -188,7 +190,7 @@ func ValidateExcludedServices(ctx context.Context, workspace *resources.Workspac
 			}
 		}
 		if err := env.validateExclusionsAgainst(graph); err != nil {
-			return fmt.Errorf("environment %q: %w", env.Name, err)
+			return err
 		}
 	}
 	return nil
@@ -253,21 +255,21 @@ func (env *Environment) validateExclusionsAgainst(graph *exclusionGraph) error {
 	}
 	for _, entry := range env.ExcludeServices {
 		if !composed[entry.Service] {
-			return fmt.Errorf("exclude-services names %q, which the workspace does not compose", entry.Service)
+			return fmt.Errorf("environment %q excludes %q, which the workspace does not compose", env.Name, entry.Service)
 		}
 		for _, consumer := range consumers[entry.Service] {
 			if excluded[consumer] || slices.Contains(entry.WithdrawnFrom, consumer) {
 				continue
 			}
-			return fmt.Errorf("exclude-services withdraws %q, but %s declares a dependency on it: name %s under its withdrawn-from to withdraw that edge with it, or stop excluding %s",
-				entry.Service, consumer, consumer, entry.Service)
+			return fmt.Errorf("environment %q withdraws %q, but %s declares a dependency on it: name %s under that environment's withdrawn-from to withdraw the edge with it, or stop excluding %s there",
+				env.Name, entry.Service, consumer, consumer, entry.Service)
 		}
 		for _, consumer := range entry.WithdrawnFrom {
 			if !slices.Contains(consumers[entry.Service], consumer) {
-				return fmt.Errorf("exclude-services %q withdrawn-from names %s, which declares no dependency on it", entry.Service, consumer)
+				return fmt.Errorf("environment %q excludes %q with a withdrawn-from naming %s, which declares no dependency on it", env.Name, entry.Service, consumer)
 			}
 			if excluded[consumer] {
-				return fmt.Errorf("exclude-services %q withdrawn-from names %s, which this environment excludes too", entry.Service, consumer)
+				return fmt.Errorf("environment %q excludes %q with a withdrawn-from naming %s, which it excludes too", env.Name, entry.Service, consumer)
 			}
 		}
 	}
@@ -277,7 +279,7 @@ func (env *Environment) validateExclusionsAgainst(graph *exclusionGraph) error {
 	for index := range graph.consumed {
 		consumption := &graph.consumed[index]
 		if excluded[resources.ServiceUnique(consumption.Module, consumption.Service)] {
-			return fmt.Errorf("solution %s consumes %s/%s/%s (api.consumes), which exclude-services withdraws from this environment", consumption.Solution, consumption.Module, consumption.Service, consumption.Endpoint)
+			return fmt.Errorf("solution %s consumes %s/%s/%s (api.consumes), which environment %q withdraws", consumption.Solution, consumption.Module, consumption.Service, consumption.Endpoint, env.Name)
 		}
 	}
 	for _, named := range env.serviceDeclarations() {
@@ -290,7 +292,7 @@ func (env *Environment) validateExclusionsAgainst(graph *exclusionGraph) error {
 			}
 		}
 		if excluded[target] {
-			return fmt.Errorf("%s names %s, which exclude-services withdraws from this environment: drop the declaration, or stop excluding %s", named.block, named.name, target)
+			return fmt.Errorf("%s names %s, which environment %q withdraws: drop the declaration, or stop excluding %s there", named.block, named.name, env.Name, target)
 		}
 	}
 	return nil
diff --git a/pkg/environments/excluded_services_test.go b/pkg/environments/excluded_services_test.go
index 48bf62ea..4ecd1fa2 100644
--- a/pkg/environments/excluded_services_test.go
+++ b/pkg/environments/excluded_services_test.go
@@ -116,7 +116,7 @@ func TestExcludeServicesRefusesWhatStillConsumesIt(t *testing.T) {
 		"a withdrawal from a non-consumer": {`    exclude-services:
       - service: shop/vault
         withdrawn-from: [shop/api, shop/cache]
-`, "withdrawn-from names shop/cache, which declares no dependency on it"},
+`, `environment "staging" excludes "shop/vault" with a withdrawn-from naming shop/cache, which declares no dependency on it`},
 		"a service the workspace does not compose": {`    exclude-services:
       - service: shop/vaults
 `, `"shop/vaults", which the workspace does not compose`},
@@ -221,7 +221,7 @@ service-dependencies:
 	reloaded, err := resources.LoadWorkspaceFromDir(context.Background(), root)
 	require.NoError(t, err)
 	err = environments.ValidateWorkspace(context.Background(), reloaded)
-	require.ErrorContains(t, err, `exclude-services withdraws "shop/cache", but portal/web declares a dependency on it`)
+	require.ErrorContains(t, err, `environment "staging" withdraws "shop/cache", but portal/web declares a dependency on it`)
 }
 
 // A module naming the excluded service its entry routes the host to a service
@@ -313,3 +313,86 @@ func TestCoordinateContractCarriesExcludedServices(t *testing.T) {
 	env.ExcludeServices[0].WithdrawnFrom[0] = "changed/consumer"
 	require.Equal(t, "saas/accounts", contract.Environment.ExcludeServices[0].WithdrawnFrom[0])
 }
+
+// TestValidateWorkspaceHoldsOnlyTheSelectedEnvironment exercises the changed
+// path directly: environments.ValidateWorkspace, which the gitops render
+// callers reach. An earlier regression for this went through NewFlow, which
+// already used ValidateEnvironmentExclusions at flow.go:484 — so it passed
+// against unfixed main and proved nothing about ValidateWorkspace.
+//
+// The fixture gives `staging` an exclusion the graph refuses (shop/api still
+// consumes shop/vault) and leaves `local` clean. A render of `local` must not
+// inherit staging's refusal; a render of `staging` must still get it; and a
+// caller that selects nothing must still hold the whole workspace.
+//
+// (`doctor workspace` is NOT such a caller: it selects an environment and
+// calls ValidateEnvironmentExclusions directly. The no-selection fallback is
+// for a caller whose subject really is the whole workspace.)
+func TestValidateWorkspaceHoldsOnlyTheSelectedEnvironment(t *testing.T) {
+	ctx := context.Background()
+	workspace := writeExclusionWorkspace(t, `    exclude-services:
+      - service: shop/vault
+`)
+	declared, err := environments.FromWorkspace(workspace)
+	require.NoError(t, err)
+	byName := map[string]*environments.Environment{}
+	for _, env := range declared {
+		if env != nil {
+			byName[env.Name] = env
+		}
+	}
+	require.Contains(t, byName, "staging")
+	require.Contains(t, byName, "local")
+	require.Empty(t, byName["local"].ExcludeServices, "local is the clean environment")
+
+	// The selected environment is the inconsistent one: still refused, so this
+	// test cannot pass by the check having been disabled.
+	err = environments.ValidateWorkspace(ctx, workspace, byName["staging"])
+	require.Error(t, err)
+	require.ErrorContains(t, err, `environment "staging" withdraws "shop/vault"`)
+
+	// The selected environment is clean: must NOT be refused over staging's
+	// declaration. This is the assertion that fails before the fix.
+	require.NoError(t, environments.ValidateWorkspace(ctx, workspace, byName["local"]),
+		"a selected environment must not be refused over another environment's exclusion")
+
+	// Nothing selected: the whole workspace is still held, preserving the
+	// default for a caller whose subject is the workspace itself.
+	err = environments.ValidateWorkspace(ctx, workspace)
+	require.Error(t, err, "with no selection every environment is still held")
+	require.ErrorContains(t, err, `environment "staging" withdraws "shop/vault"`)
+
+	// A nil selection is the same as none, not a silent skip.
+	err = environments.ValidateWorkspace(ctx, workspace, nil)
+	require.Error(t, err, "a nil selection must not skip the check")
+}
+
+// TestSelectionNarrowsTheGraphCheckAndNothingElse pins the limit of the
+// change, so the prose describing it cannot drift past the code.
+//
+// Selecting an environment narrows the GRAPH-consistency check and only that.
+// ValidateWorkspace decodes and validates every environment's declarations
+// before it compares the selected one against the graph, so a MALFORMED
+// exclusion — an unqualified name, here, in an environment nobody selected —
+// still refuses. Note what the assertions below show about where that
+// happens: the workspace LOADS and the clean environment SELECTS; it is the
+// validation that refuses, not the load. That is deliberate — a declaration
+// that cannot be parsed is not a disagreement between an environment and the
+// graph, it is a workspace that does not say what it means.
+func TestSelectionNarrowsTheGraphCheckAndNothingElse(t *testing.T) {
+	ctx := context.Background()
+	workspace := writeExclusionWorkspace(t, `    exclude-services:
+          - service: vault
+`)
+	// The clean environment selects fine — Select decodes only the one it is
+	// asked for, so the malformed declaration elsewhere does not block it.
+	local, err := environments.Select(workspace, "local")
+	require.NoError(t, err)
+
+	// But validating with that selection still refuses, because the first
+	// thing the check does is decode EVERY environment. This is the boundary:
+	// the selection narrows the graph comparison, not the parsing.
+	err = environments.ValidateWorkspace(ctx, workspace, local)
+	require.Error(t, err, "a malformed exclusion elsewhere still refuses a selected, clean environment")
+	require.ErrorContains(t, err, "exclude-services service")
+}
diff --git a/pkg/environments/workspace.go b/pkg/environments/workspace.go
index 8e5807bb..ff5bfaa1 100644
--- a/pkg/environments/workspace.go
+++ b/pkg/environments/workspace.go
@@ -191,7 +191,36 @@ func validateResourcePathComponent(kind, name string) error {
 // it earlier.
 // Loading the graph is why this is a pass separate from postLoad, mirroring
 // ValidateServiceDependencies.
-func ValidateWorkspace(ctx context.Context, workspace *resources.Workspace) error {
+// A selected environment narrows the exclusion check to that environment. The
+// exclusion graph is built from the workspace's CURRENT composition
+// (loadExclusionGraph: LoadServices, LoadModules, ConsumedEndpoints), so
+// holding EVERY environment to it refuses a flow over a declaration that is
+// not its own: an environment imported before a module overlay added a service
+// has no withdrawal for that service, and a render of a different, correct
+// environment then fails over it. Blue hit exactly that — `render --env blue`
+// refused over `staging`, whose composition predates robin/sandbox.
+//
+// So a caller that has selected an environment passes it, and gets
+// ValidateEnvironmentExclusions' contract: "a flow is held to its own
+// environment's GRAPH, never refused over another's". A caller with no
+// selection passes none and keeps holding every environment, which is right
+// for a check whose subject IS the workspace. `doctor workspace` is not that
+// caller: it selects, and calls ValidateEnvironmentExclusions directly
+// (cmd/doctor_workspace.go) rather than relying on this fallback.
+//
+// What the selection narrows is EXACTLY the graph-consistency check, and
+// nothing else in this function:
+//
+//   - FromWorkspace above decodes and validates every environment, including
+//     the SHAPE of its exclude-services (qualified names, duplicates,
+//     self-withdrawal). A malformed exclusion anywhere still refuses here.
+//   - module namespaces, host composition, service-scoped names and
+//     managed-service keys are all still held across every environment.
+//
+// Those remain whole-workspace deliberately — they are invariants of the
+// workspace, not of a selection — but they are the same cross-environment
+// shape, so narrowing them is a separate decision, not an oversight here.
+func ValidateWorkspace(ctx context.Context, workspace *resources.Workspace, selected ...*Environment) error {
 	environments, err := FromWorkspace(workspace)
 	if err != nil {
 		return err
@@ -208,7 +237,7 @@ func ValidateWorkspace(ctx context.Context, workspace *resources.Workspace) erro
 			return w.Wrap(hostErr)
 		}
 	}
-	if excludedErr := ValidateExcludedServices(ctx, workspace); excludedErr != nil {
+	if excludedErr := validateSelectedExclusions(ctx, workspace, selected); excludedErr != nil {
 		return w.Wrap(excludedErr)
 	}
 	needsGraph := false
@@ -380,3 +409,17 @@ func validateModuleNamespaces(workspace *resources.Workspace, environments []*En
 	}
 	return nil
 }
+
+// validateSelectedExclusions holds exclude-services to the workspace graph for
+// the one selected environment, or for every environment when nothing was
+// selected. A nil selection is the same as none: a caller that has no
+// environment must not silently skip the check.
+func validateSelectedExclusions(ctx context.Context, workspace *resources.Workspace, selected []*Environment) error {
+	for _, env := range selected {
+		if env == nil {
+			continue
+		}
+		return ValidateEnvironmentExclusions(ctx, workspace, env)
+	}
+	return ValidateExcludedServices(ctx, workspace)
+}
diff --git a/pkg/gitops/dev.go b/pkg/gitops/dev.go
index 1d0416a0..d9dc6402 100644
--- a/pkg/gitops/dev.go
+++ b/pkg/gitops/dev.go
@@ -134,7 +134,7 @@ func buildRenderedServiceImages(
 	rebuild bool,
 	sink orchestration.OutputSink,
 ) ([]string, error) {
-	if err := environments.ValidateWorkspace(ctx, workspace); err != nil {
+	if err := environments.ValidateWorkspace(ctx, workspace, env); err != nil {
 		return nil, err
 	}
 	if err := prepareSnapshotRegistry(ctx, env); err != nil {
diff --git a/pkg/gitops/excluded_services_test.go b/pkg/gitops/excluded_services_test.go
index f0faec6e..5d66d006 100644
--- a/pkg/gitops/excluded_services_test.go
+++ b/pkg/gitops/excluded_services_test.go
@@ -62,6 +62,60 @@ func TestRenderModuleLeavesAnExcludedServiceOutOfTheTreeAndTheInventory(t *testi
 		`rendered unit "store" is a service environment "staging" excludes`)
 }
 
+// TestRenderModuleIsNotRefusedOverAnotherEnvironmentsExclusion is the render
+// caller's half of the Blue defect, and it is the one a direct test of
+// ValidateWorkspace cannot give: it fails if RenderModule stops passing the
+// environment it was given, however correct the validator underneath is.
+//
+// It covers that one entry. The other three callers that pass a selection —
+// orchestrate.go's second call, dev.go and solution.go — are reviewed source,
+// not covered here.
+//
+// `stale` excludes shop/store while shop/api still consumes it and withdraws
+// nothing, so that environment genuinely does not hold up against the
+// workspace graph. Rendering `staging`, whose own declaration is clean, must
+// still succeed — the exclusion graph is built from the workspace's CURRENT
+// composition, so an environment imported before a module overlay added a
+// service carries no withdrawal for it, and an operator cannot repair an
+// environment the product intent does not declare.
+func TestRenderModuleIsNotRefusedOverAnotherEnvironmentsExclusion(t *testing.T) {
+	installFakeAgents(t)
+	root := t.TempDir()
+	require.NoError(t, copyTree(filepath.Join("testdata", "container-ports"), root))
+	path := filepath.Join(root, resources.WorkspaceConfigurationName)
+	data, err := os.ReadFile(path)
+	require.NoError(t, err)
+	data = append(data, []byte(`  - name: stale
+    namespace: acme
+    registry:
+      url: registry.example.com/acme
+    exclude-services:
+      - service: shop/store
+`)...)
+	require.NoError(t, os.WriteFile(path, data, 0o644))
+	ctx := context.Background()
+	workspace, err := resources.LoadWorkspaceFromDir(ctx, root)
+	require.NoError(t, err)
+	module, err := workspace.LoadModuleFromName(ctx, "shop")
+	require.NoError(t, err)
+
+	// The other environment really is inconsistent with the graph: selecting
+	// it is refused. Without this the next assertion would pass vacuously.
+	stale, err := orchestration.SelectEnvironment(workspace, "stale")
+	require.NoError(t, err)
+	_, err = RenderModule(ctx, workspace, module, stale, "acme-stale", nil)
+	require.ErrorContains(t, err, "shop/store",
+		"the inconsistent environment must still be refused when it is the selected one")
+
+	// Selecting the clean environment must not inherit that refusal.
+	staging, err := orchestration.SelectEnvironment(workspace, "staging")
+	require.NoError(t, err)
+	result, err := RenderModule(ctx, workspace, module, staging, "acme-staging", nil)
+	require.NoError(t, err, "a render is held to its own environment, never refused over another's")
+	require.DirExists(t, filepath.Join(result.Path, "services", "store"),
+		"and the service the OTHER environment excludes is rendered here")
+}
+
 // A module the environment withdraws whole renders nothing there: the render
 // refuses it by name instead of producing an empty tree.
 func TestRenderModuleRefusesAModuleTheEnvironmentWithdrawsWhole(t *testing.T) {
diff --git a/pkg/gitops/orchestrate.go b/pkg/gitops/orchestrate.go
index 45ae2375..1b99a542 100644
--- a/pkg/gitops/orchestrate.go
+++ b/pkg/gitops/orchestrate.go
@@ -46,7 +46,7 @@ func renderModuleTree(
 	if err := selectionguard.RejectUnboundExecution(workspace.Dir(), module.Dir()); err != nil {
 		return RenderResult{}, err
 	}
-	if err := environments.ValidateWorkspace(ctx, workspace); err != nil {
+	if err := environments.ValidateWorkspace(ctx, workspace, env); err != nil {
 		return RenderResult{}, err
 	}
 	if env.WithdrawsModule(module) {
@@ -618,7 +618,7 @@ func RenderService(ctx context.Context, workspace *resources.Workspace, module *
 }
 
 func renderService(ctx context.Context, workspace *resources.Workspace, module *resources.Module, service *resources.Service, env *environments.Environment, project string, build renderBuild, sink orchestration.OutputSink) (RenderResult, error) {
-	if err := environments.ValidateWorkspace(ctx, workspace); err != nil {
+	if err := environments.ValidateWorkspace(ctx, workspace, env); err != nil {
 		return RenderResult{}, err
 	}
 	if err := CheckCompositionPermissions(ctx, workspace, env, true, module.Name); err != nil {
diff --git a/pkg/gitops/solution.go b/pkg/gitops/solution.go
index ad7b3e72..ab82414b 100644
--- a/pkg/gitops/solution.go
+++ b/pkg/gitops/solution.go
@@ -59,7 +59,7 @@ func RenderSolution(ctx context.Context, req *SolutionRenderRequest) (RenderResu
 	if err := selectionguard.RejectUnboundExecution(req.Workspace.Dir(), req.Source); err != nil {
 		return RenderResult{}, err
 	}
-	if err := environments.ValidateWorkspace(ctx, req.Workspace); err != nil {
+	if err := environments.ValidateWorkspace(ctx, req.Workspace, req.Environment); err != nil {
 		return RenderResult{}, err
 	}
 	env := req.Environment
diff --git a/pkg/orchestration/excluded_services_test.go b/pkg/orchestration/excluded_services_test.go
index 70ad63af..59bfc74e 100644
--- a/pkg/orchestration/excluded_services_test.go
+++ b/pkg/orchestration/excluded_services_test.go
@@ -122,3 +122,54 @@ func TestPlanRefusesARootGroupReferenceToAnExcludedService(t *testing.T) {
 	require.ErrorContains(t, err, "from this environment (exclude-services")
 	require.ErrorContains(t, err, "platform/authority")
 }
+
+// TestFlowIsNotRefusedOverAnotherEnvironmentsExclusion is the Blue render
+// defect: a flow selecting one environment was refused over a DIFFERENT
+// environment's exclude-services.
+//
+// The exclusion graph is built from the workspace's current composition, so an
+// environment imported before a module overlay added a service carries no
+// withdrawal for it. Holding every environment to that graph meant a correct
+// `--env blue` render failed over `staging`, whose composition predates the
+// service — and the operator could not fix it from the declaration side,
+// because the product intent declares no `staging` to re-import.
+//
+// Here `stale` excludes shop/vault while shop/api still consumes it, so
+// `stale` genuinely does not hold up. Selecting `staging`, whose own
+// declaration is clean, must still succeed.
+func TestFlowIsNotRefusedOverAnotherEnvironmentsExclusion(t *testing.T) {
+	ctx := context.Background()
+	files := exclusionWorkspaceFiles("")
+	files["workspace.codefly.yaml"] = `name: acme
+layout: modules
+modules:
+    - name: shop
+environments:
+    - name: staging
+      namespace: acme
+    - name: stale
+      namespace: acme
+      exclude-services:
+          - service: shop/vault
+`
+	workspace := writeTempWorkspace(t, files)
+	module, err := workspace.LoadModuleFromName(ctx, "shop")
+	require.NoError(t, err)
+	api, err := module.LoadServiceFromName(ctx, "api")
+	require.NoError(t, err)
+
+	// The other environment really is inconsistent with the graph: selecting it
+	// refuses, which is what makes the next assertion meaningful rather than
+	// vacuous.
+	stale, err := SelectEnvironment(workspace, "stale")
+	require.NoError(t, err)
+	_, err = NewFlow(ctx, workspace, module, api, stale, RunMode)
+	require.ErrorContains(t, err, "declares a dependency on it",
+		"the inconsistent environment must still refuse when it is the selected one")
+
+	// Selecting the clean environment must not inherit that refusal.
+	staging, err := SelectEnvironment(workspace, "staging")
+	require.NoError(t, err)
+	_, err = NewFlow(ctx, workspace, module, api, staging, RunMode)
+	require.NoError(t, err, "a flow is held to its own environment, never refused over another's")
+}