diff --git a/app/Http/Controllers/ProposalOpeningController.php b/app/Http/Controllers/ProposalOpeningController.php
new file mode 100644
index 0000000..f615514
--- /dev/null
+++ b/app/Http/Controllers/ProposalOpeningController.php
@@ -0,0 +1,85 @@
+<?php
+
+namespace App\Http\Controllers;
+
+use App\Enums\PurchasingRole;
+use App\Models\ProposalOpening;
+use App\Models\PurchaseAward;
+use App\Models\Requisition;
+use App\Services\ConflictGuard;
+use App\Services\ProposalOpeningWorkflow;
+use Carbon\CarbonImmutable;
+use Illuminate\Http\RedirectResponse;
+use Illuminate\Http\Request;
+use Illuminate\Validation\ValidationException;
+use Inertia\Inertia;
+use Symfony\Component\HttpFoundation\Response;
+
+class ProposalOpeningController extends Controller
+{
+    private function access(Request $request, int $requisitionId): Requisition
+    {
+        abort_unless(in_array($request->user()->purchasing_role, [PurchasingRole::Admin, PurchasingRole::Procurement, PurchasingRole::Finance, PurchasingRole::DepartmentHead]), 403);
+
+        return Requisition::query()->visibleTo($request->user())->findOrFail($requisitionId);
+    }
+
+    public function show(Request $request, Requisition $requisition, ProposalOpeningWorkflow $workflow): Response
+    {
+        $this->access($request, $requisition->id);
+        $proposals = $workflow->proposals($requisition);
+        $query = ProposalOpening::query()->where('requisition_id', $requisition->id)->latest('revision');
+        $latest = (clone $query)->first();
+        $openings = $query->paginate(10)->withQueryString();
+        Inertia::encryptHistory();
+        $response = Inertia::render('purchases/opening', [
+            'requisition' => $requisition->only(['id', 'number', 'justification']), 'proposals' => $proposals, 'basisHash' => $workflow->basis($proposals), 'openings' => $openings,
+            'sourceChanged' => $latest && $workflow->basis($proposals) !== $latest->basis_hash,
+            'latestId' => $latest->id ?? 0,
+            'canRecord' => $request->user()->purchasing_role === PurchasingRole::Procurement && $requisition->status === 'approved' && ! PurchaseAward::query()->where('requisition_id', $requisition->id)->exists() && ! app(ConflictGuard::class)->participationBlocked($request->user(), $requisition),
+        ])->toResponse($request);
+        $response->headers->set('Cache-Control', 'private, no-store, max-age=0');
+
+        return $response;
+    }
+
+    public function store(Request $request, Requisition $requisition, ProposalOpeningWorkflow $workflow): RedirectResponse
+    {
+        $this->access($request, $requisition->id);
+        $data = $request->validate([
+            'previous_id' => 'required|integer|min:0', 'basis_hash' => 'required|string|size:64',
+            'opened_at' => 'required|date_format:Y-m-d\TH:i',
+            'timezone' => 'required|in:Africa/Maputo,Africa/Johannesburg,UTC',
+            'submission_deadline' => 'nullable|date_format:Y-m-d\TH:i|before_or_equal:opened_at',
+            'reference' => 'required|string|min:3|max:150', 'location' => 'required|string|min:3|max:300',
+            'reason' => 'required|string|min:10|max:4000', 'notes' => 'nullable|string|max:6000',
+            'quotation_ids' => 'required|array|min:1|max:100', 'quotation_ids.*' => 'required|integer|distinct',
+            'participants' => 'required|array|min:1|max:50', 'participants.*.name' => 'required|string|min:2|max:150',
+            'participants.*' => 'required|array:name,capacity,group',
+            'participants.*.capacity' => 'required|string|min:2|max:150', 'participants.*.group' => 'required|in:jury,participant',
+            'annexes' => 'nullable|array|max:30', 'annexes.*' => 'required|string|min:3|max:300',
+            'snapshot' => 'prohibited', 'tenant_id' => 'prohibited', 'created_by' => 'prohibited',
+            'confirmed' => 'accepted',
+        ]);
+        $opened = CarbonImmutable::createFromFormat('!Y-m-d\TH:i', $data['opened_at'], $data['timezone']);
+        if (! $opened || $opened->isFuture()) {
+            throw ValidationException::withMessages(['opened_at' => 'A sessão não pode estar no futuro no fuso horário indicado.']);
+        }
+        $data['opened_at'] = $opened->utc()->format('Y-m-d H:i:s');
+        $data['submission_deadline'] = empty($data['submission_deadline']) ? null : CarbonImmutable::createFromFormat('!Y-m-d\TH:i', $data['submission_deadline'], $data['timezone'])->utc()->format('Y-m-d H:i:s');
+        $data['quotation_ids'] = array_map(intval(...), $data['quotation_ids']);
+        $workflow->record($request->user(), $requisition, $data);
+
+        return back();
+    }
+
+    public function print(Request $request, ProposalOpening $opening): Response
+    {
+        $this->access($request, $opening->requisition_id);
+
+        $response = response()->view('purchases.opening', ['opening' => $opening, 'snapshot' => $opening->snapshot]);
+        $response->headers->set('Cache-Control', 'private, no-store, max-age=0');
+
+        return $response;
+    }
+}
diff --git a/app/Http/Controllers/PurchaseProcessController.php b/app/Http/Controllers/PurchaseProcessController.php
index eb51b8d..d4f7320 100644
--- a/app/Http/Controllers/PurchaseProcessController.php
+++ b/app/Http/Controllers/PurchaseProcessController.php
@@ -9,6 +9,7 @@ use App\Models\BudgetEntry;
 use App\Models\ExternalPayment;
 use App\Models\GoodsReceipt;
 use App\Models\Invoice;
+use App\Models\ProposalOpening;
 use App\Models\PurchaseAward;
 use App\Models\PurchaseOrder;
 use App\Models\PurchasePlanItem;
@@ -35,6 +36,10 @@ class PurchaseProcessController extends Controller
         $base = '/requisicoes/'.$requisition->id;
         $stages = [];
         $documents = [['label' => $requisition->number, 'kind' => 'Requisição', 'href' => $base]];
+        $opening = $purchases ? ProposalOpening::query()->where('requisition_id', $requisition->id)->latest('revision')->first(['id', 'revision']) : null;
+        if ($opening) {
+            $documents[] = ['label' => 'Acta de abertura · Versão '.$opening->revision, 'kind' => 'Abertura', 'href' => $base.'/abertura'];
+        }
         $planning = PurchasePlanItem::query()->visibleTo($actor)->where('requisition_id', $requisition->id)->first(['id', 'title']);
         if ($planning) {
             $documents[] = ['label' => $planning->title, 'kind' => 'Planeamento', 'href' => '/planeamento?item='.$planning->id];
@@ -98,7 +103,7 @@ class PurchaseProcessController extends Controller
         }
         $actions = ['requisition.created', 'requisition.updated', 'requisition.submitted', 'approval.approved', 'approval.rejected', 'equipment.technical_approved', 'equipment.technical_rejected', 'requisition.revision_created'];
         if ($purchases) {
-            $actions = [...$actions, 'award.created', 'award.approved', 'award.rejected', 'purchase_order.issued', 'cancellation.requested', 'cancellation.approved', 'cancellation.rejected'];
+            $actions = [...$actions, 'opening.recorded', 'award.created', 'award.approved', 'award.rejected', 'purchase_order.issued', 'cancellation.requested', 'cancellation.approved', 'cancellation.rejected'];
         }
         if ($inventory) {
             $actions[] = 'receipt.confirmed';
@@ -113,7 +118,7 @@ class PurchaseProcessController extends Controller
             'stages' => $stages, 'documents' => $documents, 'decisions' => $decisions, 'related' => $related,
             'cancellation' => $cancellation ? ['status' => $cancellation->status, 'href' => '/revisao-compras'] : null,
             'history' => AuditLog::query()->where('requisition_id', $requisition->id)->whereIn('action', $actions)->orderBy('id')->get(['id', 'action', 'created_at']),
-            'future' => ['Sessão de abertura e acta', 'Qualificação específica do concurso', 'Relatório de recomendação em etapas'],
+            'future' => ['Qualificação específica do concurso', 'Relatório de recomendação em etapas'],
         ])->toResponse($request);
         $response->headers->set('Cache-Control', 'private, no-store, max-age=0');
 
diff --git a/app/Models/ProposalOpening.php b/app/Models/ProposalOpening.php
new file mode 100644
index 0000000..44f035a
--- /dev/null
+++ b/app/Models/ProposalOpening.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace App\Models;
+
+use App\Models\Concerns\AppendOnlyInventoryRecord;
+use App\Models\Concerns\BelongsToTenant;
+use Illuminate\Database\Eloquent\Model;
+
+class ProposalOpening extends Model
+{
+    use AppendOnlyInventoryRecord, BelongsToTenant;
+
+    public $timestamps = false;
+
+    protected $guarded = ['id'];
+
+    protected function casts(): array
+    {
+        return ['participants' => 'array', 'annexes' => 'array', 'snapshot' => 'array'];
+    }
+}
diff --git a/app/Services/ConflictGuard.php b/app/Services/ConflictGuard.php
index a72de67..e4430ca 100644
--- a/app/Services/ConflictGuard.php
+++ b/app/Services/ConflictGuard.php
@@ -84,6 +84,7 @@ class ConflictGuard
                 'requisition.created', 'requisition.updated', 'requisition.submitted',
                 'approval.approved', 'approval.rejected', 'quotation.created', 'quotation.evaluated',
                 'award.created', 'award.approved', 'award.rejected', 'purchase_order.issued',
+                'opening.recorded',
                 'equipment.technical_approved', 'equipment.technical_rejected',
                 'invoice.created', 'invoice.validated',
                 'payment.registered', 'payment.confirmed', 'payment.rejected',
diff --git a/app/Services/ProposalOpeningWorkflow.php b/app/Services/ProposalOpeningWorkflow.php
new file mode 100644
index 0000000..52b7639
--- /dev/null
+++ b/app/Services/ProposalOpeningWorkflow.php
@@ -0,0 +1,77 @@
+<?php
+
+namespace App\Services;
+
+use App\Enums\PurchasingRole;
+use App\Models\ProposalOpening;
+use App\Models\PurchaseAward;
+use App\Models\Quotation;
+use App\Models\QuotationItem;
+use App\Models\Requisition;
+use App\Models\Supplier;
+use App\Models\Tenant;
+use App\Models\User;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Validation\ValidationException;
+
+class ProposalOpeningWorkflow
+{
+    /** @return list<array<string,mixed>> */
+    public function proposals(Requisition $requisition): array
+    {
+        return array_values(Quotation::query()->where('requisition_id', $requisition->id)->with(['supplier', 'items' => fn ($query) => $query->orderBy('id')])->orderBy('id')->get()->map(fn (Quotation $quote) => [
+            ...$quote->only(['id', 'reference', 'currency', 'subtotal_minor', 'tax_minor', 'total_minor', 'delivery_days', 'valid_until', 'payment_terms']),
+            'supplier' => $quote->supplier?->only(['id', 'name', 'nuit']),
+            'items' => $quote->items->map(fn ($item) => $item->only(['requisition_item_id', 'description', 'quantity', 'unit_price_minor', 'tax_rate', 'subtotal_minor', 'tax_minor', 'total_minor']))->all(),
+        ])->all());
+    }
+
+    /** @param list<array<string,mixed>> $proposals */
+    public function basis(array $proposals): string
+    {
+        return hash('sha256', json_encode($proposals, JSON_THROW_ON_ERROR));
+    }
+
+    /** @param array<string,mixed> $data */
+    public function record(User $actor, Requisition $requisition, array $data): ProposalOpening
+    {
+        return DB::transaction(function () use ($actor, $requisition, $data) {
+            app(ConflictGuard::class)->lockCompany($actor);
+            $actor = app(CurrentActor::class)->lock($actor, [PurchasingRole::Procurement]);
+            $requisition = Requisition::query()->lockForUpdate()->findOrFail($requisition->id);
+            app(ConflictGuard::class)->assertParticipation($actor, $requisition);
+            if ($requisition->status !== 'approved' || PurchaseAward::query()->where('requisition_id', $requisition->id)->exists()) {
+                throw ValidationException::withMessages(['opening' => 'Registe a abertura num pedido aprovado, antes da adjudicação. O histórico posterior não é reescrito.']);
+            }
+            $latest = ProposalOpening::query()->where('requisition_id', $requisition->id)->latest('revision')->first();
+            if ((int) $data['previous_id'] !== ($latest->id ?? 0)) {
+                throw ValidationException::withMessages(['previous_id' => 'A acta mudou. Actualize a página antes de registar outra versão.']);
+            }
+            $quotes = Quotation::query()->where('requisition_id', $requisition->id)->orderBy('id')->lockForUpdate()->get(['id', 'supplier_id']);
+            Supplier::query()->whereIn('id', $quotes->pluck('supplier_id'))->orderBy('id')->lockForUpdate()->get();
+            QuotationItem::query()->whereIn('quotation_id', $quotes->pluck('id'))->orderBy('id')->lockForUpdate()->get();
+            $proposals = $this->proposals($requisition);
+            if ($data['basis_hash'] !== $this->basis($proposals)) {
+                throw ValidationException::withMessages(['basis_hash' => 'As propostas mudaram desde a consulta. Confira os dados actualizados antes de registar.']);
+            }
+            $selected = array_values(array_filter($proposals, fn ($proposal) => in_array($proposal['id'], $data['quotation_ids'], true)));
+            if ($selected === [] || count($selected) !== count($data['quotation_ids'])) {
+                throw ValidationException::withMessages(['quotation_ids' => 'Seleccione apenas propostas deste processo, sem repetições.']);
+            }
+            foreach ($selected as $proposal) {
+                app(ConflictGuard::class)->assertProcess($requisition, $proposal['supplier']['id'], $actor);
+            }
+            $opening = ProposalOpening::query()->create([
+                'tenant_id' => $actor->tenant_id, 'requisition_id' => $requisition->id, 'created_by' => $actor->id, 'revision' => ($latest->revision ?? 0) + 1,
+                'opened_at' => $data['opened_at'], 'timezone' => $data['timezone'], 'submission_deadline' => $data['submission_deadline'] ?? null,
+                'reference' => $data['reference'], 'location' => $data['location'], 'reason' => $data['reason'], 'notes' => $data['notes'] ?? null,
+                'participants' => $data['participants'], 'annexes' => $data['annexes'] ?? [], 'basis_hash' => $this->basis($selected),
+                'snapshot' => ['company' => Tenant::query()->findOrFail($actor->tenant_id)->only(['id', 'name']), 'requisition' => $requisition->only(['id', 'number', 'justification']), 'author' => $actor->only(['id', 'name']), 'proposals' => $selected],
+                'created_at' => now(),
+            ]);
+            app(RequisitionWorkflow::class)->audit($actor, 'opening.recorded', $requisition, null, ['opening_id' => $opening->id, 'revision' => $opening->revision, 'previous_id' => $latest?->id, 'quotation_ids' => $data['quotation_ids']]);
+
+            return $opening;
+        });
+    }
+}
diff --git a/database/migrations/2026_10_28_000017_create_proposal_openings.php b/database/migrations/2026_10_28_000017_create_proposal_openings.php
new file mode 100644
index 0000000..48d1eee
--- /dev/null
+++ b/database/migrations/2026_10_28_000017_create_proposal_openings.php
@@ -0,0 +1,37 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('proposal_openings', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('tenant_id')->constrained()->restrictOnDelete();
+            $table->foreignId('requisition_id')->constrained()->restrictOnDelete();
+            $table->foreignId('created_by')->constrained('users')->restrictOnDelete();
+            $table->unsignedInteger('revision');
+            $table->dateTime('opened_at');
+            $table->string('timezone', 64);
+            $table->dateTime('submission_deadline')->nullable();
+            $table->string('reference', 150);
+            $table->string('location', 300);
+            $table->text('reason');
+            $table->text('notes')->nullable();
+            $table->json('participants');
+            $table->json('annexes');
+            $table->json('snapshot');
+            $table->string('basis_hash', 64);
+            $table->timestamp('created_at');
+            $table->unique(['requisition_id', 'revision']);
+        });
+    }
+
+    public function down(): void
+    {
+        throw new LogicException('Preservar as actas e as suas versões.');
+    }
+};
diff --git a/docs/abertura-concorrencia-postgresql.json b/docs/abertura-concorrencia-postgresql.json
new file mode 100644
index 0000000..d920bd5
--- /dev/null
+++ b/docs/abertura-concorrencia-postgresql.json
@@ -0,0 +1,33 @@
+{
+    "tested_at_utc": "2026-10-28T16:45:17+00:00",
+    "separate_database": true,
+    "transport": "Independent PHP service transactions and PostgreSQL connections",
+    "scenarios": [
+        {
+            "name": "competing_initial_versions",
+            "passed": true,
+            "overlapping_lock_waits": 2,
+            "immutable_versions": 1
+        },
+        {
+            "name": "competing_corrections",
+            "passed": true,
+            "overlapping_lock_waits": 2,
+            "immutable_versions": 2
+        },
+        {
+            "name": "revoked_role",
+            "passed": true,
+            "overlapping_lock_waits": 2,
+            "immutable_versions": 0
+        },
+        {
+            "name": "changed_basis",
+            "passed": true,
+            "overlapping_lock_waits": 2,
+            "immutable_versions": 0
+        }
+    ],
+    "passed": true,
+    "test_database_dropped": true
+}
diff --git a/docs/abertura-migracao-000017.json b/docs/abertura-migracao-000017.json
new file mode 100644
index 0000000..cdc4261
--- /dev/null
+++ b/docs/abertura-migracao-000017.json
@@ -0,0 +1,16 @@
+{
+    "verified_at_utc": "2026-10-28T16:46:10+00:00",
+    "migration": "2026_10_28_000017_create_proposal_openings",
+    "batch": 18,
+    "backup_created": true,
+    "backup_bytes": 291397,
+    "restore_verified": true,
+    "restored_tables": 54,
+    "restore_database_dropped": true,
+    "business_records_unchanged": true,
+    "existing_constraints_preserved": true,
+    "env_unchanged": true,
+    "proposal_openings_count": 0,
+    "purchase_plan_milestones_count": 0,
+    "operational_validation": false
+}
diff --git a/docs/exemplos-orquestracao-compras.md b/docs/exemplos-orquestracao-compras.md
index 0711364..e74f838 100644
--- a/docs/exemplos-orquestracao-compras.md
+++ b/docs/exemplos-orquestracao-compras.md
@@ -2,7 +2,8 @@
 
 Evolução do roteiro: a visão única foi entregue em `76d2463`. O incremento de
 planeamento acrescenta itens por empresa, responsáveis, marcos e datas
-previstas/realizadas, com ligação posterior às requisições. Actas, qualificação
+previstas/realizadas, com ligação posterior às requisições. O registo documental
+opcional da abertura e actas por versão também foi implementado. Qualificação
 específica e avaliação em novas modalidades continuam por implementar. Estes
 avanços não importam os processos históricos nem aprovam as regras de
 cancelamento de ordens emitidas.
diff --git a/docs/validacao-tecnica.md b/docs/validacao-tecnica.md
index 80766e3..91a7901 100644
--- a/docs/validacao-tecnica.md
+++ b/docs/validacao-tecnica.md
@@ -1,5 +1,73 @@
 # Validação técnica do SGC — 28 de Outubro de 2026
 
+## Incremento: sessão de abertura e actas por versão
+
+Nas propostas existe o acesso «Sessão de abertura e actas», em
+`/requisicoes/{requisition}/abertura`. Compras pode registar uma sessão num
+pedido aprovado, antes de existir adjudicação. O registo é opcional; não
+introduz um concurso público obrigatório, um número mínimo de propostas,
+um júri obrigatório ou um novo circuito financeiro em todas as empresas.
+
+O operador declara referência, local, data/hora, fuso horário, intervenientes,
+qualidade em que participam, observações e referências de anexos, selecciona
+as propostas e confirma a conferência. As propostas seleccionadas são
+copiadas no servidor com fornecedor, referência, valores e linhas; não se
+aceitam valores de uma acta enviados pelo cliente. Uma impressão autenticada
+usa a cópia preservada, incluindo nome da empresa e autor do registo.
+Não contém pontuações ou uma recomendação de adjudicação.
+
+As datas são interpretadas no fuso declarado, guardadas em UTC e apresentadas
+nesse fuso. Este primeiro âmbito suporta Africa/Johannesburg, Africa/Maputo e
+UTC; a interface começa pelo fuso do contexto local. Sessões futuras e prazo
+de apresentação posterior à sessão são recusados. O prazo é declarado; não
+se presume que a data de criação de uma cotação no SGC seja a sua data real
+de entrega pelo concorrente.
+
+Correcções criam versões novas, com fundamento e referência à versão anterior
+na auditoria. As versões guardadas não são editadas ou eliminadas pela
+aplicação. Uma base de propostas alterada desde a consulta ou uma versão
+anterior desactualizada é recusada. A interface permite conferir a base
+actualizada sem apagar os textos introduzidos. Propostas posteriormente
+adicionadas ou alteradas não entram nas actas anteriores; uma divergência é
+assinalada na consulta. Não se alterou a política de recepção de cotações.
+
+Os nomes dos intervenientes são declarações, não assinaturas digitais
+verificadas. A impressão disponibiliza espaço para assinaturas manuscritas.
+As referências de anexos não representam carregamento ou validação de
+ficheiros. Registar uma acta não avalia propostas, não certifica a realização
+da sessão, não adjudica, não reserva orçamento e não autoriza compras.
+Alterações documentais depois da adjudicação exigem um circuito futuro;
+este incremento conserva as actas anteriores para consulta, sem as reescrever.
+
+Administração, Compras, Finanças e chefias autorizadas consultam; apenas
+Compras regista. Mantêm-se isolamento entre empresas, âmbito departamental,
+verificação de conflitos e revalidação do operador dentro da transacção.
+Solicitantes e Armazém não ganham acesso a preços ou actas. Consulta e
+impressão usam `private, no-store`; o histórico Inertia é cifrado. Os registos
+aparecem nos documentos e eventos da visão única conforme o perfil.
+
+A migração aditiva 000017 foi aplicada no batch 18 após backup privado de
+291397 bytes e restauro verificado de 54 tabelas. Dados anteriores,
+restrições e `.env` foram preservados; não foram criadas actas fictícias na
+base de negócio. Ver `abertura-migracao-000017.json`. Backup e manifesto
+ficam fora do Git.
+
+Resultado: **443 testes aprovados, 2 ignorados, 3431 asserções**, incluindo
+11 testes novos de snapshots, versões, base desactualizada, impressão,
+fuso horário, validação, segregação, empresas/departamentos, revogação de
+perfil, rollback de auditoria, imutabilidade e escape de texto. Quatro
+cenários PostgreSQL passaram, cada um com duas ligações e duas esperas de
+bloqueio simultâneas: versões iniciais concorrentes, correcções concorrentes,
+perfil revogado e base alterada durante a espera. A base temporária exclusiva
+foi eliminada. Ver `abertura-concorrencia-postgresql.json`.
+
+PHPStan, Pint, TypeScript e build passaram. A revisão visual da interface e
+da impressão permanece pendente pela indisponibilidade do navegador. Não se
+declara validação operacional de concursos, assinaturas, orçamentos ou regras
+de cancelamento de ordens emitidas. Publicação de concursos, propostas
+seladas, qualificação por etapas e novos métodos de avaliação continuam
+pendentes; os exemplos locais não os tornam obrigações universais.
+
 ## Incremento: planeamento por empresa
 
 O menu Compras inclui `/planeamento`. Administração e Compras registam itens
diff --git a/resources/js/pages/purchases/opening.tsx b/resources/js/pages/purchases/opening.tsx
new file mode 100644
index 0000000..2d90786
--- /dev/null
+++ b/resources/js/pages/purchases/opening.tsx
@@ -0,0 +1,560 @@
+import { Head, Link, useForm } from '@inertiajs/react';
+import { FormErrors, PageTitle, Panel } from '@/components/procurement';
+import { Button } from '@/components/ui/button';
+import { Input } from '@/components/ui/input';
+import { Label } from '@/components/ui/label';
+
+type Participant = {
+    name: string;
+    capacity: string;
+    group: 'jury' | 'participant';
+};
+type Proposal = {
+    id: number;
+    reference: string;
+    currency: string;
+    supplier: { name: string } | null;
+    subtotal_minor: number;
+    tax_minor: number;
+    total_minor: number;
+};
+type Opening = {
+    id: number;
+    revision: number;
+    opened_at: string;
+    timezone: string;
+    location: string;
+    reference: string;
+    reason: string;
+    notes: string | null;
+    participants: Participant[];
+    annexes: string[];
+    created_at: string;
+    snapshot: { author: { name: string }; proposals: Proposal[] };
+};
+type Props = {
+    requisition: { id: number; number: string; justification: string };
+    proposals: Proposal[];
+    basisHash: string;
+    latestId: number;
+    sourceChanged: boolean;
+    canRecord: boolean;
+    openings: {
+        data: Opening[];
+        prev_page_url: string | null;
+        next_page_url: string | null;
+    };
+};
+const selectClass = 'h-10 w-full rounded-md border bg-background px-3 text-sm';
+const amount = (minor: number, currency: string) =>
+    `${(minor / 100).toLocaleString('pt-PT', { minimumFractionDigits: 2, maximumFractionDigits: 2 })} ${currency}`;
+const sessionDate = (utc: string, timezone: string) =>
+    new Date(`${utc.replace(' ', 'T')}Z`).toLocaleString('pt-PT', {
+        timeZone: timezone,
+        dateStyle: 'short',
+        timeStyle: 'short',
+    });
+
+function OpeningForm({
+    requisition,
+    proposals,
+    basisHash,
+    latestId,
+}: Pick<Props, 'requisition' | 'proposals' | 'basisHash' | 'latestId'>) {
+    const form = useForm({
+        previous_id: latestId,
+        basis_hash: basisHash,
+        opened_at: '',
+        timezone: 'Africa/Johannesburg',
+        submission_deadline: '',
+        reference: '',
+        location: '',
+        reason: '',
+        notes: '',
+        quotation_ids: [] as number[],
+        participants: [
+            { name: '', capacity: '', group: 'participant' },
+        ] as Participant[],
+        annexes_text: '',
+        confirmed: false,
+    });
+    const participant = (index: number, change: Partial<Participant>) =>
+        form.setData(
+            'participants',
+            form.data.participants.map((entry, position) =>
+                position === index ? { ...entry, ...change } : entry,
+            ),
+        );
+    return (
+        <form
+            onSubmit={(event) => {
+                event.preventDefault();
+                form.transform(({ annexes_text, ...data }) => ({
+                    ...data,
+                    annexes: annexes_text
+                        .split('\n')
+                        .map((line) => line.trim())
+                        .filter(Boolean),
+                }));
+                form.post(`/requisicoes/${requisition.id}/abertura`, {
+                    preserveScroll: true,
+                });
+            }}
+            className="space-y-5"
+        >
+            {form.data.basis_hash !== basisHash && (
+                <div className="rounded-lg border border-amber-300 p-4 text-sm">
+                    <p>
+                        As propostas foram actualizadas. Confira os valores
+                        abaixo; os textos introduzidos foram mantidos.
+                    </p>
+                    <Button
+                        type="button"
+                        variant="outline"
+                        className="mt-3"
+                        onClick={() => {
+                            form.setData('basis_hash', basisHash);
+                            form.setData('confirmed', false);
+                            form.setData(
+                                'quotation_ids',
+                                form.data.quotation_ids.filter((id) =>
+                                    proposals.some(
+                                        (proposal) => proposal.id === id,
+                                    ),
+                                ),
+                            );
+                        }}
+                    >
+                        Usar a base actual para nova conferência
+                    </Button>
+                </div>
+            )}
+            <div className="grid gap-4 sm:grid-cols-2">
+                <Label>
+                    Referência do processo ou concurso
+                    <Input
+                        required
+                        minLength={3}
+                        maxLength={150}
+                        value={form.data.reference}
+                        onChange={(event) =>
+                            form.setData('reference', event.target.value)
+                        }
+                    />
+                </Label>
+                <Label>
+                    Local da sessão
+                    <Input
+                        required
+                        minLength={3}
+                        maxLength={300}
+                        value={form.data.location}
+                        onChange={(event) =>
+                            form.setData('location', event.target.value)
+                        }
+                    />
+                </Label>
+                <Label>
+                    Data e hora da sessão
+                    <Input
+                        type="datetime-local"
+                        required
+                        value={form.data.opened_at}
+                        onChange={(event) =>
+                            form.setData('opened_at', event.target.value)
+                        }
+                    />
+                </Label>
+                <Label>
+                    Fuso horário
+                    <select
+                        className={selectClass}
+                        value={form.data.timezone}
+                        onChange={(event) =>
+                            form.setData('timezone', event.target.value)
+                        }
+                    >
+                        <option value="Africa/Johannesburg">
+                            Africa/Johannesburg (UTC+2)
+                        </option>
+                        <option value="Africa/Maputo">
+                            Africa/Maputo (UTC+2)
+                        </option>
+                        <option value="UTC">UTC</option>
+                    </select>
+                </Label>
+                <Label>
+                    Limite declarado de apresentação (opcional)
+                    <Input
+                        type="datetime-local"
+                        value={form.data.submission_deadline}
+                        onChange={(event) =>
+                            form.setData(
+                                'submission_deadline',
+                                event.target.value,
+                            )
+                        }
+                    />
+                </Label>
+            </div>
+            <fieldset className="space-y-3">
+                <legend className="mb-3 text-sm font-semibold">
+                    Propostas incluídas na sessão
+                </legend>
+                <p className="text-sm text-muted-foreground">
+                    Os valores são copiados da aplicação. Seleccione e confira
+                    as propostas incluídas.
+                </p>
+                {proposals.map((proposal) => (
+                    <Label
+                        key={proposal.id}
+                        className="flex items-start gap-3 rounded-lg border p-3"
+                    >
+                        <input
+                            type="checkbox"
+                            checked={form.data.quotation_ids.includes(
+                                proposal.id,
+                            )}
+                            onChange={(event) =>
+                                form.setData(
+                                    'quotation_ids',
+                                    event.target.checked
+                                        ? [
+                                              ...form.data.quotation_ids,
+                                              proposal.id,
+                                          ]
+                                        : form.data.quotation_ids.filter(
+                                              (id) => id !== proposal.id,
+                                          ),
+                                )
+                            }
+                        />
+                        <span>
+                            {proposal.supplier?.name ??
+                                'Fornecedor indisponível'}{' '}
+                            · {proposal.reference}
+                            <span className="mt-1 block text-xs text-muted-foreground">
+                                Sem IVA:{' '}
+                                {amount(
+                                    proposal.subtotal_minor,
+                                    proposal.currency,
+                                )}{' '}
+                                · IVA:{' '}
+                                {amount(proposal.tax_minor, proposal.currency)}{' '}
+                                · Total:{' '}
+                                {amount(
+                                    proposal.total_minor,
+                                    proposal.currency,
+                                )}
+                            </span>
+                        </span>
+                    </Label>
+                ))}
+            </fieldset>
+            <fieldset className="space-y-3">
+                <legend className="mb-3 text-sm font-semibold">
+                    Intervenientes declarados
+                </legend>
+                {form.data.participants.map((entry, index) => (
+                    <div
+                        key={index}
+                        className="grid gap-3 rounded-lg border p-3 sm:grid-cols-3"
+                    >
+                        <Label>
+                            Nome
+                            <Input
+                                required
+                                minLength={2}
+                                maxLength={150}
+                                value={entry.name}
+                                onChange={(event) =>
+                                    participant(index, {
+                                        name: event.target.value,
+                                    })
+                                }
+                            />
+                        </Label>
+                        <Label>
+                            Qualidade ou função
+                            <Input
+                                required
+                                minLength={2}
+                                maxLength={150}
+                                value={entry.capacity}
+                                onChange={(event) =>
+                                    participant(index, {
+                                        capacity: event.target.value,
+                                    })
+                                }
+                            />
+                        </Label>
+                        <Label>
+                            Participação
+                            <select
+                                className={selectClass}
+                                value={entry.group}
+                                onChange={(event) =>
+                                    participant(index, {
+                                        group:
+                                            event.target.value === 'jury'
+                                                ? 'jury'
+                                                : 'participant',
+                                    })
+                                }
+                            >
+                                <option value="participant">
+                                    Participante
+                                </option>
+                                <option value="jury">Júri</option>
+                            </select>
+                        </Label>
+                        {form.data.participants.length > 1 && (
+                            <Button
+                                type="button"
+                                variant="ghost"
+                                onClick={() =>
+                                    form.setData(
+                                        'participants',
+                                        form.data.participants.filter(
+                                            (_, position) => position !== index,
+                                        ),
+                                    )
+                                }
+                            >
+                                Retirar interveniente
+                            </Button>
+                        )}
+                    </div>
+                ))}
+                <Button
+                    type="button"
+                    variant="outline"
+                    disabled={form.data.participants.length >= 50}
+                    onClick={() =>
+                        form.setData('participants', [
+                            ...form.data.participants,
+                            { name: '', capacity: '', group: 'participant' },
+                        ])
+                    }
+                >
+                    Adicionar interveniente
+                </Button>
+            </fieldset>
+            <Label>
+                Referências de anexos (uma por linha)
+                <textarea
+                    className="min-h-20 rounded-md border bg-background p-3 text-sm"
+                    value={form.data.annexes_text}
+                    onChange={(event) =>
+                        form.setData('annexes_text', event.target.value)
+                    }
+                />
+            </Label>
+            <p className="text-xs text-muted-foreground">
+                São referências declaradas; não são ficheiros carregados nem
+                assinaturas verificadas.
+            </p>
+            <Label>
+                Observações
+                <textarea
+                    className="min-h-24 rounded-md border bg-background p-3 text-sm"
+                    maxLength={6000}
+                    value={form.data.notes}
+                    onChange={(event) =>
+                        form.setData('notes', event.target.value)
+                    }
+                />
+            </Label>
+            <Label>
+                Fundamento do registo ou da correcção
+                <textarea
+                    className="min-h-20 rounded-md border bg-background p-3 text-sm"
+                    required
+                    minLength={10}
+                    maxLength={4000}
+                    value={form.data.reason}
+                    onChange={(event) =>
+                        form.setData('reason', event.target.value)
+                    }
+                />
+            </Label>
+            <Label className="flex items-start gap-3">
+                <input
+                    type="checkbox"
+                    checked={form.data.confirmed}
+                    onChange={(event) =>
+                        form.setData('confirmed', event.target.checked)
+                    }
+                    required
+                />
+                <span>
+                    Conferi os dados da sessão e as propostas seleccionadas
+                    antes de guardar esta versão.
+                </span>
+            </Label>
+            <FormErrors errors={form.errors} />
+            <Button disabled={form.processing || !proposals.length}>
+                {latestId
+                    ? 'Registar nova versão da acta'
+                    : 'Registar acta de abertura'}
+            </Button>
+        </form>
+    );
+}
+
+export default function OpeningPage(props: Props) {
+    const { requisition, openings, canRecord, sourceChanged, latestId } = props;
+    return (
+        <>
+            <Head title={`Abertura · ${requisition.number}`} />
+            <div className="mx-auto flex max-w-7xl flex-col gap-6 p-5 lg:p-8">
+                <PageTitle
+                    eyebrow={requisition.number}
+                    title="Abertura de propostas"
+                    description={requisition.justification}
+                    action={
+                        <Button asChild variant="outline">
+                            <Link
+                                href={`/requisicoes/${requisition.id}/processo`}
+                            >
+                                Ver processo
+                            </Link>
+                        </Button>
+                    }
+                />
+                <p className="rounded-xl border bg-muted/30 p-4 text-sm text-muted-foreground">
+                    Registo documental opcional antes da adjudicação. A acta não
+                    avalia propostas, verifica assinaturas ou autoriza compras.
+                    Uma correcção gera outra versão e conserva as anteriores.
+                </p>
+                {sourceChanged && (
+                    <p className="rounded-xl border border-amber-200 bg-amber-50 p-4 text-sm text-amber-950">
+                        Há propostas não incluídas ou dados actuais diferentes
+                        da última acta. Alterações posteriores não entram
+                        automaticamente nos documentos guardados.
+                    </p>
+                )}
+                {canRecord ? (
+                    <Panel
+                        title={
+                            latestId
+                                ? 'Nova versão da acta'
+                                : 'Registar sessão de abertura'
+                        }
+                    >
+                        <OpeningForm key={latestId} {...props} />
+                    </Panel>
+                ) : (
+                    <p className="text-sm text-muted-foreground">
+                        O registo está disponível a Compras num pedido aprovado
+                        e sem adjudicação. As versões anteriores continuam
+                        disponíveis.
+                    </p>
+                )}
+                {openings.data.map((opening) => (
+                    <Panel
+                        key={opening.id}
+                        title={`${opening.reference} · Versão ${opening.revision}`}
+                        description={`${sessionDate(opening.opened_at, opening.timezone)} · ${opening.timezone} · ${opening.location}`}
+                    >
+                        <p className="text-sm">
+                            Registada por {opening.snapshot.author.name} em{' '}
+                            {sessionDate(opening.created_at, opening.timezone)}.
+                        </p>
+                        <p className="mt-3 text-sm whitespace-pre-wrap">
+                            {opening.reason}
+                        </p>
+                        <ul className="mt-4 divide-y">
+                            {opening.snapshot.proposals.map((proposal) => (
+                                <li
+                                    key={proposal.id}
+                                    className="flex flex-wrap justify-between gap-2 py-3 text-sm"
+                                >
+                                    <span>
+                                        {proposal.supplier?.name ??
+                                            'Fornecedor indisponível'}{' '}
+                                        · {proposal.reference}
+                                    </span>
+                                    <strong>
+                                        {amount(
+                                            proposal.total_minor,
+                                            proposal.currency,
+                                        )}
+                                    </strong>
+                                </li>
+                            ))}
+                        </ul>
+                        <details className="mt-3 text-sm">
+                            <summary className="cursor-pointer underline">
+                                Intervenientes, observações e referências de
+                                anexos
+                            </summary>
+                            <ul className="mt-3 space-y-2">
+                                {opening.participants.map((entry, index) => (
+                                    <li key={index}>
+                                        {entry.name} · {entry.capacity} ·{' '}
+                                        {entry.group === 'jury'
+                                            ? 'Júri'
+                                            : 'Participante'}
+                                    </li>
+                                ))}
+                            </ul>
+                            <p className="mt-3 whitespace-pre-wrap">
+                                {opening.notes || 'Sem observações.'}
+                            </p>
+                            <ul className="mt-3 list-inside list-disc">
+                                {opening.annexes.map((annex, index) => (
+                                    <li key={index}>{annex}</li>
+                                ))}
+                            </ul>
+                        </details>
+                        <Button asChild variant="outline" className="mt-5">
+                            <a
+                                href={`/actas/${opening.id}/imprimir`}
+                                target="_blank"
+                                rel="noopener noreferrer"
+                            >
+                                Abrir acta para impressão
+                            </a>
+                        </Button>
+                    </Panel>
+                ))}
+                {!openings.data.length && (
+                    <Panel title="Ainda não existe acta">
+                        <p className="text-sm text-muted-foreground">
+                            A ausência deste registo opcional não cria uma nova
+                            etapa obrigatória.
+                        </p>
+                    </Panel>
+                )}
+                <nav
+                    aria-label="Versões das actas"
+                    className="flex justify-between gap-3"
+                >
+                    {openings.prev_page_url ? (
+                        <Button asChild variant="outline">
+                            <Link href={openings.prev_page_url}>
+                                Versões mais recentes
+                            </Link>
+                        </Button>
+                    ) : (
+                        <span />
+                    )}
+                    {openings.next_page_url && (
+                        <Button asChild variant="outline">
+                            <Link href={openings.next_page_url}>
+                                Versões anteriores
+                            </Link>
+                        </Button>
+                    )}
+                </nav>
+            </div>
+        </>
+    );
+}
+OpeningPage.layout = {
+    breadcrumbs: [
+        { title: 'Requisições', href: '/requisicoes' },
+        { title: 'Abertura de propostas', href: '#' },
+    ],
+};
diff --git a/resources/js/pages/purchases/process.tsx b/resources/js/pages/purchases/process.tsx
index 191e121..341d1c3 100644
--- a/resources/js/pages/purchases/process.tsx
+++ b/resources/js/pages/purchases/process.tsx
@@ -48,6 +48,7 @@ const labels: Record<string, string> = {
     issued: 'Emitida',
 };
 const events: Record<string, string> = {
+    'opening.recorded': 'Versão da acta de abertura registada',
     'requisition.created': 'Requisição criada',
     'requisition.updated': 'Requisição actualizada',
     'requisition.submitted': 'Requisição submetida',
diff --git a/resources/js/pages/quotations/show.tsx b/resources/js/pages/quotations/show.tsx
index 86b8596..70caee3 100644
--- a/resources/js/pages/quotations/show.tsx
+++ b/resources/js/pages/quotations/show.tsx
@@ -110,6 +110,12 @@ export default function Comparison({
                 >
                     Adjudicação, aprovações do valor final e ordem de compra
                 </Link>
+                <Link
+                    className="text-sm font-medium underline"
+                    href={`/requisicoes/${requisition.id}/abertura`}
+                >
+                    Sessão de abertura e actas
+                </Link>
                 <Link
                     className="text-sm text-teal-700"
                     href={`/requisicoes/${requisition.id}`}
diff --git a/resources/views/purchases/opening.blade.php b/resources/views/purchases/opening.blade.php
new file mode 100644
index 0000000..9505890
--- /dev/null
+++ b/resources/views/purchases/opening.blade.php
@@ -0,0 +1,47 @@
+<!DOCTYPE html>
+<html lang="pt">
+<head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>Acta de abertura · {{ $opening->reference }} · SGC</title>
+    <style>
+        @page { size: A4; margin: 17mm; }
+        * { box-sizing: border-box; }
+        body { margin: 24px auto; max-width: 960px; color: #111; font: 12px/1.5 Arial, sans-serif; }
+        header { border-bottom: 3px solid #ed1c24; padding-bottom: 12px; }
+        h1 { font-size: 22px; margin-bottom: 4px; } h2 { font-size: 15px; margin-top: 24px; }
+        p, td, th { overflow-wrap: anywhere; } .pre { white-space: pre-wrap; }
+        table { width: 100%; border-collapse: collapse; margin-top: 12px; }
+        th, td { border: 1px solid #ccc; padding: 8px; text-align: left; vertical-align: top; }
+        th { background: #f2f2f2; } thead { display: table-header-group; } tr { break-inside: avoid; }
+        .notice { border: 1px solid #aaa; padding: 10px; margin-top: 16px; } .small { color: #444; font-size: 10px; }
+        .signature { min-width: 120px; padding-top: 28px; } footer { border-top: 1px solid #ddd; margin-top: 28px; padding-top: 12px; }
+        button { padding: 10px 18px; } @media print { body { margin: 0; max-width: none; } .no-print { display: none; } }
+    </style>
+</head>
+<body>
+    <button type="button" class="no-print" onclick="window.print()">Imprimir acta</button>
+    <header><strong>SGC · Sistema de Gestão de Compras</strong><p>{{ $snapshot['company']['name'] }}</p></header>
+    <h1>Acta de sessão de abertura de propostas</h1>
+    <p><strong>{{ $opening->reference }}</strong> · Versão {{ $opening->revision }} · {{ $snapshot['requisition']['number'] }}</p>
+    <p class="pre">Objecto: {{ $snapshot['requisition']['justification'] }}</p>
+    <p>Data e hora declaradas da sessão: {{ \Carbon\CarbonImmutable::parse($opening->opened_at, 'UTC')->timezone($opening->timezone)->format('d/m/Y H:i') }}<br>Fuso horário: {{ $opening->timezone }}<br>Local: {{ $opening->location }}</p>
+    @if($opening->submission_deadline)<p>Limite declarado para apresentação: {{ \Carbon\CarbonImmutable::parse($opening->submission_deadline, 'UTC')->timezone($opening->timezone)->format('d/m/Y H:i') }}</p>@endif
+    <div class="notice">Registo documental para conferência e assinatura. Os nomes são declarados; o SGC não valida assinaturas nem certifica a realização da sessão. Esta acta não constitui avaliação, recomendação, adjudicação ou autorização financeira.</div>
+    <h2>Intervenientes declarados</h2>
+    <table><thead><tr><th>Nome</th><th>Qualidade</th><th>Participação</th><th>Assinatura manuscrita</th></tr></thead><tbody>
+    @foreach($opening->participants as $participant)<tr><td>{{ $participant['name'] }}</td><td>{{ $participant['capacity'] }}</td><td>{{ $participant['group'] === 'jury' ? 'Júri' : 'Participante' }}</td><td class="signature">____________________</td></tr>@endforeach
+    </tbody></table>
+    <h2>Mapa das propostas registadas na aplicação</h2>
+    <p>Valores preservados à data deste registo, para conferência com os dados da sessão. Não inclui propostas adicionadas ou alteradas posteriormente.</p>
+    <table><thead><tr><th>Ordem</th><th>Concorrente e referência</th><th>Sem IVA</th><th>IVA</th><th>Total</th></tr></thead><tbody>
+    @foreach($snapshot['proposals'] as $index => $proposal)<tr><td>{{ $index + 1 }}</td><td>{{ $proposal['supplier']['name'] ?? 'Fornecedor indisponível' }}<br>{{ $proposal['reference'] }}</td><td>{{ number_format($proposal['subtotal_minor'] / 100, 2, ',', '.') }} {{ $proposal['currency'] }}</td><td>{{ number_format($proposal['tax_minor'] / 100, 2, ',', '.') }} {{ $proposal['currency'] }}</td><td>{{ number_format($proposal['total_minor'] / 100, 2, ',', '.') }} {{ $proposal['currency'] }}</td></tr>@endforeach
+    </tbody></table>
+    <h2>Observações</h2><p class="pre">{{ $opening->notes ?: 'Sem observações registadas.' }}</p>
+    <h2>Referências de anexos</h2>
+    @if(count($opening->annexes))<ul>@foreach($opening->annexes as $annex)<li>{{ $annex }}</li>@endforeach</ul>@else<p>Sem referências de anexos registadas.</p>@endif
+    <p class="small">As referências acima não significam que os ficheiros ou assinaturas foram carregados ou verificados no SGC.</p>
+    <h2>Fundamento do registo desta versão</h2><p class="pre">{{ $opening->reason }}</p>
+    <footer class="small">Registado por {{ $snapshot['author']['name'] }} em {{ \Carbon\CarbonImmutable::parse($opening->created_at, 'UTC')->timezone($opening->timezone)->format('d/m/Y H:i') }} · {{ $opening->timezone }}.<br>SGC · Sistema de Gestão de Compras · Documento do processo {{ $snapshot['requisition']['number'] }}.</footer>
+</body>
+</html>
diff --git a/routes/web.php b/routes/web.php
index 08ebd1d..989b4da 100644
--- a/routes/web.php
+++ b/routes/web.php
@@ -9,6 +9,7 @@ use App\Http\Controllers\ExternalPaymentController;
 use App\Http\Controllers\GoodsReceiptController;
 use App\Http\Controllers\InvestmentPolicyController;
 use App\Http\Controllers\InvoiceController;
+use App\Http\Controllers\ProposalOpeningController;
 use App\Http\Controllers\PurchaseControlController;
 use App\Http\Controllers\PurchaseController;
 use App\Http\Controllers\PurchasePlanningController;
@@ -32,6 +33,9 @@ Route::middleware(['auth', 'verified'])->group(function () {
     Route::post('empresa/iniciar', [CompanyController::class, 'store'])->name('company.store');
 
     Route::middleware(EnsureCompanyIsConfigured::class)->group(function () {
+        Route::get('requisicoes/{requisition}/abertura', [ProposalOpeningController::class, 'show'])->name('openings.show');
+        Route::post('requisicoes/{requisition}/abertura', [ProposalOpeningController::class, 'store']);
+        Route::get('actas/{opening}/imprimir', [ProposalOpeningController::class, 'print'])->name('openings.print');
         Route::get('planeamento', [PurchasePlanningController::class, 'index'])->name('planning.index');
         Route::post('planeamento', [PurchasePlanningController::class, 'store']);
         Route::post('planeamento/{item}/responsavel', [PurchasePlanningController::class, 'assign']);
diff --git a/tests/Concurrency/opening-worker.php b/tests/Concurrency/opening-worker.php
new file mode 100644
index 0000000..71131f1
--- /dev/null
+++ b/tests/Concurrency/opening-worker.php
@@ -0,0 +1,34 @@
+<?php
+
+use App\Models\Requisition;
+use App\Models\User;
+use App\Services\ProposalOpeningWorkflow;
+use Illuminate\Contracts\Console\Kernel;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Validation\ValidationException;
+use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
+
+require __DIR__.'/../../vendor/autoload.php';
+$database = $argv[1] ?? '';
+if (! preg_match('/^compras_receipts_test_[a-f0-9]{12}$/', $database)) {
+    throw new LogicException('Base de teste inválida.');
+}
+$app = require __DIR__.'/../../bootstrap/app.php';
+$app->make(Kernel::class)->bootstrap();
+if (! $app->environment('testing') || DB::connection()->getDatabaseName() !== $database) {
+    throw new LogicException('Worker não isolado.');
+}
+DB::select('select set_config(?, ?, false)', ['application_name', 'sgc_opening_'.$argv[4]]);
+$pid = DB::selectOne('select pg_backend_pid() as pid')->pid;
+$actor = User::query()->findOrFail($argv[2]);
+auth()->guard()->setUser($actor);
+$data = json_decode(stream_get_contents(STDIN), true, 512, JSON_THROW_ON_ERROR);
+try {
+    app(ProposalOpeningWorkflow::class)->record($actor, Requisition::query()->findOrFail($argv[3]), $data);
+    $status = 200;
+} catch (ValidationException) {
+    $status = 422;
+} catch (HttpExceptionInterface $exception) {
+    $status = $exception->getStatusCode();
+}
+echo json_encode(['status' => $status, 'backend_pid' => $pid], JSON_THROW_ON_ERROR);
diff --git a/tests/Concurrency/run-openings.php b/tests/Concurrency/run-openings.php
new file mode 100644
index 0000000..829fd86
--- /dev/null
+++ b/tests/Concurrency/run-openings.php
@@ -0,0 +1,132 @@
+<?php
+
+use App\Models\AuditLog;
+use App\Models\ProposalOpening;
+use App\Services\ProposalOpeningWorkflow;
+use Illuminate\Contracts\Console\Kernel;
+use Illuminate\Support\Facades\Artisan;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+use Symfony\Component\Process\Process;
+
+require __DIR__.'/../../vendor/autoload.php';
+foreach (['APP_ENV' => 'testing', 'CACHE_STORE' => 'array', 'SESSION_DRIVER' => 'array', 'QUEUE_CONNECTION' => 'sync', 'MAIL_MAILER' => 'array'] as $key => $value) {
+    putenv($key.'='.$value);
+    $_ENV[$key] = $_SERVER[$key] = $value;
+}
+$app = require __DIR__.'/../../bootstrap/app.php';
+$app->make(Kernel::class)->bootstrap();
+require __DIR__.'/../Support/ProposalOpeningFixture.php';
+$original = DB::connection();
+if ($original->getDriverName() !== 'pgsql') {
+    throw new LogicException('Exige PostgreSQL.');
+}
+$config = $original->getConfig();
+$admin = $original->getPdo();
+$database = 'compras_receipts_test_'.bin2hex(random_bytes(6));
+$created = false;
+$processes = [];
+$report = ['tested_at_utc' => gmdate('c'), 'separate_database' => true, 'transport' => 'Independent PHP service transactions and PostgreSQL connections', 'scenarios' => []];
+try {
+    $admin->exec('CREATE DATABASE "'.$database.'"');
+    $created = true;
+    config(['database.connections.pgsql' => [...$config, 'database' => $database, 'url' => null]]);
+    DB::purge('pgsql');
+    DB::setDefaultConnection('pgsql');
+    Schema::clearResolvedInstance('db.schema');
+    app()->forgetInstance('db.schema');
+    if (DB::connection()->getDatabaseName() !== $database || Schema::getConnection()->getDatabaseName() !== $database) {
+        throw new LogicException('Migração fora do isolamento recusada.');
+    }
+    Artisan::call('migrate', ['--database' => 'pgsql', '--force' => true]);
+    $workerEnv = ['APP_ENV' => 'testing', 'DB_CONNECTION' => 'pgsql', 'DB_URL' => '', 'DB_DATABASE' => $database, 'DB_HOST' => $config['host'], 'DB_PORT' => (string) $config['port'], 'DB_USERNAME' => $config['username'], 'DB_PASSWORD' => $config['password'], 'CACHE_STORE' => 'array', 'SESSION_DRIVER' => 'array'];
+    foreach (['competing_initial_versions', 'competing_corrections', 'revoked_role', 'changed_basis'] as $scenario) {
+        $f = proposalOpeningFixture();
+        $actor = $f['issuer'];
+        $data = $f['service_data'];
+        if ($scenario === 'competing_corrections') {
+            $initial = app(ProposalOpeningWorkflow::class)->record($actor, $f['r'], $data);
+            $data['previous_id'] = $initial->id;
+        }
+        $connection = DB::connection();
+        $connection->beginTransaction();
+        $connection->table('tenants')->where('id', $actor->tenant_id)->lockForUpdate()->first();
+        $processes = [];
+        foreach (['A', 'B'] as $suffix) {
+            $process = new Process([PHP_BINARY, __DIR__.'/opening-worker.php', $database, (string) $actor->id, (string) $f['r']->id, $suffix], base_path(), $workerEnv);
+            $process->setInput(json_encode([...$data, 'notes' => 'Versão concorrente fictícia '.$suffix], JSON_THROW_ON_ERROR));
+            $process->setTimeout(40);
+            $process->start();
+            $processes[] = $process;
+        }
+        $statement = $admin->prepare("SELECT count(*) FROM pg_stat_activity WHERE datname = ? AND application_name IN ('sgc_opening_A','sgc_opening_B') AND wait_event_type = 'Lock'");
+        $deadline = microtime(true) + 20;
+        do {
+            $statement->execute([$database]);
+            $waits = (int) $statement->fetchColumn();
+            if ($waits === 2) {
+                break;
+            }
+            foreach ($processes as $process) {
+                if (! $process->isRunning()) {
+                    throw new RuntimeException('Worker terminou antes do bloqueio: '.$process->getErrorOutput());
+                }
+            }
+            usleep(20000);
+        } while (microtime(true) < $deadline);
+        if ($scenario === 'revoked_role') {
+            $connection->table('users')->where('id', $actor->id)->update(['purchasing_role' => 'finance']);
+        }
+        if ($scenario === 'changed_basis') {
+            $connection->table('quotations')->where('id', $f['quote']->id)->update(['reference' => 'Referência alterada durante a espera']);
+        }
+        $connection->commit();
+        if ($waits !== 2) {
+            throw new RuntimeException('Sem sobreposição de bloqueios.');
+        }
+        $results = [];
+        foreach ($processes as $process) {
+            $process->wait();
+            if (! $process->isSuccessful()) {
+                throw new RuntimeException('Falha do worker: '.$process->getErrorOutput());
+            }
+            $results[] = json_decode($process->getOutput(), true, 512, JSON_THROW_ON_ERROR);
+        }
+        $statuses = array_column($results, 'status');
+        sort($statuses);
+        $expected = match ($scenario) {
+            'revoked_role' => [403, 403], 'changed_basis' => [422, 422], default => [200, 422]
+        };
+        $count = ProposalOpening::query()->count();
+        $expectedCount = match ($scenario) {
+            'competing_initial_versions' => 1, 'competing_corrections' => 2, default => 0
+        };
+        if ($statuses !== $expected || count(array_unique(array_column($results, 'backend_pid'))) !== 2 || $count !== $expectedCount || AuditLog::query()->where('action', 'opening.recorded')->count() !== $expectedCount) {
+            throw new RuntimeException('Versão concorrente inesperada.');
+        }
+        if ($count && (int) ProposalOpening::query()->max('revision') !== $expectedCount) {
+            throw new RuntimeException('Numeração inconsistente.');
+        }
+        if ($scenario === 'competing_corrections' && $initial->refresh()->notes !== $f['data']['notes']) {
+            throw new RuntimeException('Versão anterior alterada.');
+        }
+        $report['scenarios'][] = ['name' => $scenario, 'passed' => true, 'overlapping_lock_waits' => $waits, 'immutable_versions' => $count];
+    }
+    $report['passed'] = true;
+} finally {
+    foreach ($processes as $process) {
+        if ($process->isRunning()) {
+            $process->stop();
+        }
+    }
+    if (isset($connection) && $connection->transactionLevel() > 0) {
+        $connection->rollBack();
+    }
+    DB::disconnect('pgsql');
+    if ($created && $database !== $original->getDatabaseName() && preg_match('/^compras_receipts_test_[a-f0-9]{12}$/', $database)) {
+        $admin->exec('DROP DATABASE "'.$database.'"');
+        $report['test_database_dropped'] = true;
+    }
+}
+file_put_contents(base_path('docs/abertura-concorrencia-postgresql.json'), json_encode($report, JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR).PHP_EOL);
+echo json_encode($report, JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR).PHP_EOL;
diff --git a/tests/Feature/ProposalOpeningTest.php b/tests/Feature/ProposalOpeningTest.php
new file mode 100644
index 0000000..5ae6635
--- /dev/null
+++ b/tests/Feature/ProposalOpeningTest.php
@@ -0,0 +1,133 @@
+<?php
+
+use App\Enums\PurchasingRole;
+use App\Models\AuditLog;
+use App\Models\BudgetEntry;
+use App\Models\Department;
+use App\Models\ProposalOpening;
+use App\Models\PurchaseAward;
+use App\Models\Supplier;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Services\ProposalOpeningWorkflow;
+use Illuminate\Support\Facades\DB;
+use Inertia\Testing\AssertableInertia as Assert;
+
+require_once __DIR__.'/../Support/ProposalOpeningFixture.php';
+
+beforeEach(function () {
+    $this->f = proposalOpeningFixture();
+    $this->url = '/requisicoes/'.$this->f['r']->id.'/abertura';
+    $this->actingAs($this->f['issuer']);
+});
+
+function recordOpening(object $test, array $changes = []): ProposalOpening
+{
+    $test->post($test->url, [...$test->f['data'], ...$changes])->assertSessionHasNoErrors();
+
+    return ProposalOpening::query()->latest('revision')->firstOrFail();
+}
+
+test('opening is an optional documentary snapshot without approval or financial effects', function () {
+    $opening = recordOpening($this);
+    expect($opening->revision)->toBe(1)->and($opening->snapshot['proposals'][0]['total_minor'])->toBe(10000)
+        ->and($opening->snapshot['proposals'][0])->not->toHaveKey('evaluations')->and(BudgetEntry::query()->count())->toBe(0)
+        ->and($this->f['r']->refresh()->status)->toBe('approved')->and(PurchaseAward::query()->count())->toBe(0);
+    $this->get($this->url)->assertOk()->assertHeader('Cache-Control', 'max-age=0, no-store, private')->assertInertia(fn (Assert $page) => $page->component('purchases/opening')->where('sourceChanged', false)->where('latestId', $opening->id));
+    $this->get('/requisicoes/'.$this->f['r']->id.'/processo')->assertInertia(fn (Assert $page) => $page->where('documents', fn ($documents) => collect($documents)->contains('kind', 'Abertura')));
+});
+
+test('opening corrections append a new version and refuse stale predecessor ids', function () {
+    $first = recordOpening($this);
+    $second = recordOpening($this, ['previous_id' => $first->id, 'notes' => 'Nova observação sem apagar o passado']);
+    expect($second->revision)->toBe(2)->and($first->refresh()->notes)->toBe('Observações fictícias');
+    $this->post($this->url, [...$this->f['data'], 'previous_id' => $first->id])->assertSessionHasErrors('previous_id');
+    expect(ProposalOpening::query()->count())->toBe(2);
+});
+
+test('opening refuses a proposal basis changed after the form was loaded', function () {
+    $this->f['quote']->update(['reference' => 'Referência actualizada']);
+    $this->post($this->url, $this->f['data'])->assertSessionHasErrors('basis_hash');
+    expect(ProposalOpening::query()->count())->toBe(0);
+});
+
+test('printed acta preserves supplier and price snapshots after source changes', function () {
+    $opening = recordOpening($this);
+    $name = $opening->snapshot['proposals'][0]['supplier']['name'];
+    Supplier::query()->whereKey($this->f['quote']->supplier_id)->update(['name' => 'Nome posterior fictício']);
+    $this->f['quote']->update(['total_minor' => 20000]);
+    $this->get($this->url)->assertInertia(fn (Assert $page) => $page->where('sourceChanged', true));
+    $this->get('/actas/'.$opening->id.'/imprimir')->assertOk()->assertHeader('Cache-Control', 'max-age=0, no-store, private')->assertSee($name)->assertDontSee('Nome posterior fictício')->assertSee('100,00')->assertSee('não valida assinaturas');
+});
+
+test('opening stores local session time as UTC and prints the declared timezone', function () {
+    $opening = recordOpening($this);
+    expect($opening->opened_at)->toBe($this->f['service_data']['opened_at'])->and($opening->timezone)->toBe('Africa/Johannesburg');
+    $this->get('/actas/'.$opening->id.'/imprimir')->assertSee('Africa/Johannesburg');
+    $this->post($this->url, [...$this->f['data'], 'previous_id' => $opening->id, 'opened_at' => now()->addHour()->timezone('Africa/Johannesburg')->format('Y-m-d\TH:i')])->assertSessionHasErrors('opened_at');
+});
+
+test('opening validates deadline confirmation and declared participants', function () {
+    $this->post($this->url, [...$this->f['data'], 'confirmed' => false])->assertSessionHasErrors('confirmed');
+    $this->post($this->url, [...$this->f['data'], 'submission_deadline' => now()->addDay()->timezone('Africa/Johannesburg')->format('Y-m-d\TH:i')])->assertSessionHasErrors('submission_deadline');
+    $this->post($this->url, [...$this->f['data'], 'participants' => []])->assertSessionHasErrors('participants');
+    $this->post($this->url, [...$this->f['data'], 'snapshot' => ['signed' => true]])->assertSessionHasErrors('snapshot');
+});
+
+test('opening cannot rewrite a process after an award or record a draft request', function () {
+    $this->f['r']->update(['status' => 'draft']);
+    $this->post($this->url, $this->f['data'])->assertSessionHasErrors('opening');
+    $this->f['r']->update(['status' => 'approved']);
+    PurchaseAward::query()->create($this->f['award_attributes']);
+    $this->post($this->url, $this->f['data'])->assertSessionHasErrors('opening');
+    expect(ProposalOpening::query()->count())->toBe(0);
+});
+
+test('opening is restricted by role department company and authentication including print', function () {
+    $opening = recordOpening($this);
+    $print = '/actas/'.$opening->id.'/imprimir';
+    $this->actingAs($this->f['receiver'])->get($this->url)->assertForbidden();
+    $this->get($print)->assertForbidden();
+    $finance = User::factory()->create(['tenant_id' => $this->f['tenant']->id, 'purchasing_role' => PurchasingRole::Finance]);
+    $this->actingAs($finance)->get($this->url)->assertOk();
+    $this->get($print)->assertOk();
+    $this->post($this->url, [...$this->f['data'], 'previous_id' => $opening->id])->assertForbidden();
+    $department = Department::query()->create(['tenant_id' => $this->f['tenant']->id, 'name' => 'Outro departamento']);
+    $head = User::factory()->create(['tenant_id' => $this->f['tenant']->id, 'department_id' => $department->id, 'purchasing_role' => PurchasingRole::DepartmentHead]);
+    $this->actingAs($head)->get($print)->assertNotFound();
+    $other = Tenant::query()->create(['name' => 'Outra empresa fictícia']);
+    $this->actingAs(User::factory()->create(['tenant_id' => $other->id, 'purchasing_role' => PurchasingRole::Admin]))->get($print)->assertNotFound();
+    auth()->logout();
+    $this->get($print)->assertRedirect('/login');
+});
+
+test('opening rejects revoked procurement roles and never accepts foreign proposals', function () {
+    $original = $this->f;
+    $foreign = proposalOpeningFixture();
+    $this->actingAs($original['issuer']);
+    $this->post($this->url, [...$original['data'], 'quotation_ids' => [$foreign['quote']->id]])->assertSessionHasErrors('quotation_ids');
+    DB::table('users')->where('id', $original['issuer']->id)->update(['purchasing_role' => 'finance']);
+    $this->post($this->url, $original['data'])->assertForbidden();
+    expect(ProposalOpening::query()->count())->toBe(0);
+});
+
+test('opening audit failure rolls back the entire immutable document', function () {
+    AuditLog::creating(function (AuditLog $event) {
+        if ($event->action === 'opening.recorded') {
+            throw new RuntimeException('Falha fictícia de auditoria');
+        }
+    });
+    try {
+        expect(fn () => app(ProposalOpeningWorkflow::class)->record($this->f['issuer'], $this->f['r'], $this->f['service_data']))->toThrow(RuntimeException::class);
+    } finally {
+        AuditLog::flushEventListeners();
+    }
+    expect(ProposalOpening::query()->count())->toBe(0);
+});
+
+test('opening documents are immutable and user text is escaped for printing', function () {
+    $opening = recordOpening($this, ['notes' => '<script>alert("ficticio")</script>']);
+    $this->get('/actas/'.$opening->id.'/imprimir')->assertDontSee('<script>', false)->assertSee('&lt;script&gt;', false);
+    expect(fn () => $opening->update(['notes' => 'Alteração proibida']))->toThrow(LogicException::class);
+    expect(fn () => $opening->delete())->toThrow(LogicException::class);
+});
diff --git a/tests/Feature/PurchaseProcessTest.php b/tests/Feature/PurchaseProcessTest.php
index 636792e..3bca1b3 100644
--- a/tests/Feature/PurchaseProcessTest.php
+++ b/tests/Feature/PurchaseProcessTest.php
@@ -21,7 +21,7 @@ test('process overview links records without declaring partial execution complet
             ->where('stages.7.state', 'recorded')
             ->where('stages.7.detail', '1 registadas; 0 validadas. O registo não equivale a validação.')
             ->where('stages.8.state', 'not_started')
-            ->has('future', 3)
+            ->has('future', 2)
             ->where('documents', fn ($documents) => collect($documents)->contains('label', $f['invoice']->number)));
 });
 
diff --git a/tests/Support/ProposalOpeningFixture.php b/tests/Support/ProposalOpeningFixture.php
new file mode 100644
index 0000000..7b3275f
--- /dev/null
+++ b/tests/Support/ProposalOpeningFixture.php
@@ -0,0 +1,28 @@
+<?php
+
+use App\Models\PurchaseAward;
+use App\Models\Quotation;
+use App\Services\ProposalOpeningWorkflow;
+use Carbon\CarbonImmutable;
+use Illuminate\Support\Facades\DB;
+
+require_once __DIR__.'/ReceiptFixture.php';
+
+/** receiptFixture refuses execution outside the isolated test database. */
+function proposalOpeningFixture(): array
+{
+    $f = receiptFixture();
+    auth()->guard()->setUser($f['issuer']);
+    $award = PurchaseAward::query()->findOrFail($f['order']->purchase_award_id);
+    $awardAttributes = $award->getAttributes();
+    unset($awardAttributes['id']);
+    DB::table('purchase_order_items')->where('purchase_order_id', $f['order']->id)->delete();
+    DB::table('purchase_orders')->where('id', $f['order']->id)->delete();
+    DB::table('purchase_awards')->where('id', $award->id)->delete();
+    $quote = Quotation::query()->where('requisition_id', $f['r']->id)->firstOrFail();
+    $workflow = app(ProposalOpeningWorkflow::class);
+    $data = ['previous_id' => 0, 'basis_hash' => $workflow->basis($workflow->proposals($f['r'])), 'opened_at' => now()->subMinute()->timezone('Africa/Johannesburg')->format('Y-m-d\TH:i'), 'timezone' => 'Africa/Johannesburg', 'submission_deadline' => null, 'reference' => 'ABERTURA-FICTICIA', 'location' => 'Sala exclusivamente fictícia', 'reason' => 'Registo exclusivamente fictício de teste', 'notes' => 'Observações fictícias', 'quotation_ids' => [$quote->id], 'participants' => [['name' => 'Participante fictício', 'capacity' => 'Secretariado de teste', 'group' => 'participant']], 'annexes' => ['Lista fictícia de presenças'], 'confirmed' => true];
+    $serviceData = [...$data, 'opened_at' => CarbonImmutable::createFromFormat('!Y-m-d\TH:i', $data['opened_at'], $data['timezone'])->utc()->format('Y-m-d H:i:s')];
+
+    return [...$f, 'quote' => $quote, 'data' => $data, 'service_data' => $serviceData, 'award_attributes' => $awardAttributes];
+}
diff --git a/tests/Support/apply-openings-migration.php b/tests/Support/apply-openings-migration.php
new file mode 100644
index 0000000..14ddb2e
--- /dev/null
+++ b/tests/Support/apply-openings-migration.php
@@ -0,0 +1,111 @@
+<?php
+
+// Explicit operational entry point: backup, restore verification, then only migration 000017.
+use Illuminate\Contracts\Console\Kernel;
+use Illuminate\Support\Facades\Artisan;
+use Illuminate\Support\Facades\DB;
+use Symfony\Component\Process\Process;
+
+require __DIR__.'/../../vendor/autoload.php';
+$app = require __DIR__.'/../../bootstrap/app.php';
+$app->make(Kernel::class)->bootstrap();
+$connection = DB::connection();
+if ($connection->getDriverName() !== 'pgsql' || $connection->getDatabaseName() !== 'compras_dev' || ! $app->environment('local')) {
+    throw new LogicException('Aplicação recusada fora de compras_dev/local.');
+}
+$pdo = $connection->getPdo();
+$migration = '2026_10_28_000017_create_proposal_openings';
+if ($pdo->query("SELECT count(*) FROM migrations WHERE migration = '$migration'")->fetchColumn() > 0) {
+    throw new LogicException('Migração já aplicada; não repetir.');
+}
+$config = $connection->getConfig();
+$bin = 'C:/Program Files/PostgreSQL/17/bin/';
+foreach (['pg_dump.exe', 'pg_restore.exe'] as $tool) {
+    if (! is_file($bin.$tool)) {
+        throw new LogicException('Ferramentas PostgreSQL 17 ausentes.');
+    }
+}
+$envHash = hash_file('sha256', base_path('.env'));
+$directory = storage_path('app/private/backups/proposal-openings-000017-'.gmdate('Ymd-His').'-'.bin2hex(random_bytes(3)));
+if (! mkdir($directory, 0700, true)) {
+    throw new RuntimeException('Não foi possível criar backup privado.');
+}
+$env = ['PGHOST' => $config['host'], 'PGPORT' => (string) $config['port'], 'PGUSER' => $config['username'], 'PGPASSWORD' => $config['password'], 'PGSSLMODE' => $config['sslmode'] ?? 'prefer'];
+$quote = fn (string $name) => '"'.str_replace('"', '""', $name).'"';
+$columns = [];
+$fingerprints = function (PDO $db, array $tables) use ($quote, &$columns): array {
+    $result = [];
+    foreach ($tables as $table) {
+        $rows = $db->query('SELECT md5(row_to_json(t)::text) FROM (SELECT '.implode(', ', array_map($quote, $columns[$table])).' FROM public.'.$quote($table).') t')->fetchAll(PDO::FETCH_COLUMN);
+        sort($rows, SORT_STRING);
+        $result[$table] = ['count' => count($rows), 'sha256' => hash('sha256', implode('\n', $rows))];
+    }
+
+    return $result;
+};
+$tables = $pdo->query("SELECT tablename FROM pg_tables WHERE schemaname = 'public' ORDER BY tablename")->fetchAll(PDO::FETCH_COLUMN);
+foreach ($tables as $table) {
+    $statement = $pdo->prepare("SELECT column_name FROM information_schema.columns WHERE table_schema = 'public' AND table_name = ? ORDER BY ordinal_position");
+    $statement->execute([$table]);
+    $columns[$table] = $statement->fetchAll(PDO::FETCH_COLUMN);
+}
+$restoreDatabase = 'compras_restore_check_'.bin2hex(random_bytes(6));
+$restoreCreated = false;
+try {
+    // pg_dump and the manifest read exactly the same committed snapshot.
+    $pdo->beginTransaction();
+    $pdo->exec('SET TRANSACTION ISOLATION LEVEL REPEATABLE READ, READ ONLY');
+    $snapshot = $pdo->query('SELECT pg_export_snapshot()')->fetchColumn();
+    $backupState = $fingerprints($pdo, $tables);
+    $dump = new Process([$bin.'pg_dump.exe', '--format=custom', '--no-owner', '--no-acl', '--snapshot='.$snapshot, '--file='.$directory.'/database.dump', '--dbname='.$config['database']], base_path(), $env);
+    $dump->setTimeout(120);
+    $dump->run();
+    if (! $dump->isSuccessful()) {
+        throw new RuntimeException('Falha no backup PostgreSQL; migração não executada.');
+    }
+    $pdo->commit();
+    $pdo->exec('CREATE DATABASE '.$quote($restoreDatabase));
+    $restoreCreated = true;
+    $restore = new Process([$bin.'pg_restore.exe', '--exit-on-error', '--no-owner', '--no-acl', '--dbname='.$restoreDatabase, $directory.'/database.dump'], base_path(), $env);
+    $restore->setTimeout(120);
+    $restore->run();
+    if (! $restore->isSuccessful()) {
+        throw new RuntimeException('Restauro de verificação falhou; migração não executada.');
+    }
+    config(['database.connections.budget_restore' => [...$config, 'url' => null, 'database' => $restoreDatabase]]);
+    $restored = DB::connection('budget_restore')->getPdo();
+    if ($fingerprints($restored, $tables) !== $backupState) {
+        throw new RuntimeException('Restauro não corresponde ao backup; migração recusada.');
+    }
+    file_put_contents($directory.'/manifest.json', json_encode(['tables' => $backupState, 'columns' => $columns, 'dump_sha256' => hash_file('sha256', $directory.'/database.dump')], JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
+    file_put_contents($directory.'/RECUPERACAO.txt', "Backup custom PostgreSQL 17 verificado por restauro numa base separada.\nUsar pg_restore --exit-on-error --no-owner --no-acl --dbname=NOVA_BASE database.dump.\nAs credenciais pertencem ao ambiente local e não estão neste manifesto.\nNão restaurar por cima da base existente.\n");
+    DB::disconnect('budget_restore');
+    unset($restored);
+    $pdo->exec('DROP DATABASE '.$quote($restoreDatabase));
+    $restoreCreated = false;
+    $businessTables = array_values(array_diff($tables, ['migrations', 'sessions', 'cache', 'cache_locks', 'jobs', 'failed_jobs', 'job_batches']));
+    $before = $fingerprints($pdo, $businessTables);
+    $oldMigrations = $pdo->query('SELECT id, migration, batch FROM migrations ORDER BY id')->fetchAll(PDO::FETCH_ASSOC);
+    $constraints = $pdo->query("SELECT conname, pg_get_constraintdef(oid) AS definition FROM pg_constraint WHERE connamespace = 'public'::regnamespace ORDER BY conname, definition")->fetchAll(PDO::FETCH_ASSOC);
+    $exit = Artisan::call('migrate', ['--path' => 'database/migrations/'.$migration.'.php', '--force' => true]);
+    if ($exit !== 0) {
+        throw new RuntimeException('Migração falhou; consultar backup privado.');
+    }
+    $after = $fingerprints($pdo, $businessTables);
+    $newMigrations = $pdo->query('SELECT id, migration, batch FROM migrations ORDER BY id')->fetchAll(PDO::FETCH_ASSOC);
+    $newConstraints = $pdo->query("SELECT conname, pg_get_constraintdef(oid) AS definition FROM pg_constraint WHERE connamespace = 'public'::regnamespace ORDER BY conname, definition")->fetchAll(PDO::FETCH_ASSOC);
+    if ($before !== $after || array_slice($newMigrations, 0, count($oldMigrations)) !== $oldMigrations || count($newMigrations) !== count($oldMigrations) + 1 || array_diff(array_map('serialize', $constraints), array_map('serialize', $newConstraints)) !== [] || hash_file('sha256', base_path('.env')) !== $envHash) {
+        throw new RuntimeException('Verificação de preservação falhou; não executar mais escritas.');
+    }
+    $report = ['verified_at_utc' => gmdate('c'), 'migration' => $migration, 'batch' => (int) end($newMigrations)['batch'], 'backup_created' => true, 'backup_bytes' => filesize($directory.'/database.dump'), 'restore_verified' => true, 'restored_tables' => count($tables), 'restore_database_dropped' => true, 'business_records_unchanged' => true, 'existing_constraints_preserved' => true, 'env_unchanged' => true, 'proposal_openings_count' => (int) $pdo->query('SELECT count(*) FROM proposal_openings')->fetchColumn(), 'purchase_plan_milestones_count' => (int) $pdo->query('SELECT count(*) FROM purchase_plan_milestones')->fetchColumn(), 'operational_validation' => false];
+    file_put_contents(base_path('docs/abertura-migracao-000017.json'), json_encode($report, JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR).PHP_EOL);
+    echo json_encode($report, JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR).PHP_EOL;
+} finally {
+    if ($pdo->inTransaction()) {
+        $pdo->rollBack();
+    }
+    DB::disconnect('budget_restore');
+    if ($restoreCreated && preg_match('/^compras_restore_check_[a-f0-9]{12}$/', $restoreDatabase) && $restoreDatabase !== $connection->getDatabaseName()) {
+        $pdo->exec('DROP DATABASE '.$quote($restoreDatabase));
+    }
+}