feat(services): builder selection, resource reservations, static builder (C3)

services.builder picks the build strategy per service: auto detects from
repo contents (Dockerfile → railpack → nixpacks), explicit overrides force
a builder, and static builds assets in a node stage then serves them from
an nginx image (static_build_cmd/static_dir, port 80 default).

- cpu_reserve/memory_reserve → Docker CPU shares + MemoryReservation;
  cpu/memory stay hard caps (NanoCPUs/Memory). Empty string clears.
- app_settings.default_cpu/default_memory override service-create
  fallbacks; capacity_policy=block fails deploys whose requested memory
  exceeds node capacity (default warn logs via slog).
- Resource specs are validated — "512mb" fails instead of silently
  dropping the limit.
- Fixes: deployments.go hardcoded nixpacks (auto-detect was dead code);
  DockerfileBuilder passed the Dockerfile *path* as build-context content;
  BuildImage never drained the daemon stream so builds could abort and
  errors went unseen — stream is now consumed and errorDetail surfaced.
- CLI: --builder/--cpu-reserve/--memory-reserve/--static-cmd/--static-dir
  on create+update; MCP args on services create/update; UI Build &
  Resources card; OpenAPI + llms.txt + CLI.md.

Verified live: static build of a real repo → nginx image → deployed;
reserves reach HostConfig (shares=256, MemoryReservation=128Mi);
validation rejects bad specs; builder persists + clears.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/backend/internal/api/deployments.go

@@ -4,9 +4,11 @@ import (
 	"containr/internal/database"
 	"containr/internal/deployment"
 	"containr/internal/deployqueue"
+	"containr/internal/docker"
 	"context"
 	"errors"
 	"fmt"
+	"log/slog"
 	"net/http"
 	"strings"
 	"time"
@@ -232,6 +234,9 @@ func handleCreateDeployment(c *gin.Context) {
 		        COALESCE(s.replicas, 1), COALESCE(s.port, 0),
 		        COALESCE(s.domain, ''), COALESCE(s.healthcheck_path, ''),
 		        COALESCE(s.restart_policy, 'unless-stopped'),
+		        COALESCE(s.builder, 'auto'), COALESCE(s.cpu_reserve, ''),
+		        COALESCE(s.memory_reserve, ''), COALESCE(s.static_build_cmd, ''),
+		        COALESCE(s.static_dir, ''),
 		        s.created_at, s.updated_at, p.owner_id
 		 FROM services s
 		 JOIN projects p ON s.project_id = p.id
@@ -242,7 +247,9 @@ func handleCreateDeployment(c *gin.Context) {
 		&service.Image, &service.Command, &service.Environment, &service.GitRepo,
 		&service.GitBranch, &service.BuildPath, &service.CPU, &service.Memory,
 		&service.Replicas, &service.Port, &service.Domain, &service.HealthCheckPath,
-		&service.RestartPolicy, &service.CreatedAt, &service.UpdatedAt, &projectOwner,
+		&service.RestartPolicy, &service.Builder, &service.CPUReserve,
+		&service.MemoryReserve, &service.StaticBuildCmd, &service.StaticDir,
+		&service.CreatedAt, &service.UpdatedAt, &projectOwner,
 	)
 
 	if err != nil {
@@ -401,6 +408,13 @@ func runDeploymentAndSyncWithImage(
 	// ephemeral ports.
 	_ = db.QueryRow(`SELECT published_port FROM services WHERE id = $1`, service.ID).Scan(&publishedPort)
 
+	publicPort := int32(service.Port)
+	if service.Builder == "static" && publicPort == 0 {
+		// The static builder's image is nginx — route to its default port
+		// unless the user picked another.
+		publicPort = 80
+	}
+
 	maintenanceMode, basicAuthUsers := serviceAccess(db, service.ID)
 	maintURL := ""
 	if maintenanceMode {
@@ -417,7 +431,7 @@ func runDeploymentAndSyncWithImage(
 			Command:       command,
 			Environment:   env,
 			Replicas:      replicas,
-			PublicPort:    int32(service.Port),
+			PublicPort:    publicPort,
 			PublishedPort: publishedPort,
 			Domain:        service.Domain,
 			HealthPath:    service.HealthCheckPath,
@@ -425,8 +439,10 @@ func runDeploymentAndSyncWithImage(
 			VolumeMounts:  loadServiceVolumes(db, service.ID),
 			Domains:       serviceDomainNames(db, service.ID, service.Domain),
 			Resources: deployment.ResourceLimits{
-				MemoryBytes: parseMemoryLimit(service.Memory),
-				CPUQuota:    parseCPULimit(service.CPU),
+				MemoryBytes:       parseMemoryLimit(service.Memory),
+				MemoryReservation: parseMemoryLimit(service.MemoryReserve),
+				CPUQuota:          parseCPULimit(service.CPU),
+				CPUShares:         parseCPUReserveShares(service.CPUReserve),
 			},
 			Maintenance:    maintenanceMode,
 			MaintenanceURL: maintURL,
@@ -452,13 +468,33 @@ func runDeploymentAndSyncWithImage(
 			PrebuiltImage: service.Image,
 		}
 	} else {
+		// "auto" leaves BuildType empty so the manager detects it; the static
+		// builder additionally feeds its generated Dockerfile the service's
+		// build command and output dir.
+		buildType := ""
+		if service.Builder != "" && service.Builder != "auto" {
+			buildType = service.Builder
+		}
 		deployReq.BuildConfig = &deployment.BuildConfig{
-			BuildType:  "nixpacks",
+			BuildType:  buildType,
 			SourcePath: sourcePath,
 			Branch:     req.Branch,
 			Commit:     req.CommitHash,
 			NoCache:    req.NoCache,
 		}
+		if buildType == "static" {
+			deployReq.BuildConfig.BuildCommand = firstNonEmpty(service.StaticBuildCmd, "npm ci && npm run build")
+			deployReq.BuildConfig.BuildArgs = map[string]string{"STATIC_DIR": firstNonEmpty(service.StaticDir, "dist")}
+		}
+	}
+
+	if msg := capacityCheck(parentCtx, db, engine.DockerClient(), service, replicas); msg != "" {
+		failedAt := time.Now()
+		_, _ = db.Exec(
+			`UPDATE deployments SET status = 'failed', error = $1, completed_at = $2, updated_at = $2 WHERE id = $3`,
+			msg, failedAt, dbDeployment.ID,
+		)
+		return
 	}
 
 	engineDeployment, err := engine.Deploy(ctx, deployReq)
@@ -822,6 +858,9 @@ func handleRollbackDeployment(c *gin.Context) {
 			        COALESCE(s.replicas, 1), COALESCE(s.port, 0),
 			        COALESCE(s.domain, ''), COALESCE(s.healthcheck_path, ''),
 			        COALESCE(s.restart_policy, 'unless-stopped'),
+			        COALESCE(s.builder, 'auto'), COALESCE(s.cpu_reserve, ''),
+			        COALESCE(s.memory_reserve, ''), COALESCE(s.static_build_cmd, ''),
+			        COALESCE(s.static_dir, ''),
 			        s.created_at, s.updated_at
 			 FROM services s WHERE s.id = $1`, serviceID,
 		).Scan(
@@ -829,7 +868,9 @@ func handleRollbackDeployment(c *gin.Context) {
 			&service.Image, &service.Command, &service.Environment, &service.GitRepo,
 			&service.GitBranch, &service.BuildPath, &service.CPU, &service.Memory,
 			&service.Replicas, &service.Port, &service.Domain, &service.HealthCheckPath,
-			&service.RestartPolicy, &service.CreatedAt, &service.UpdatedAt,
+			&service.RestartPolicy, &service.Builder, &service.CPUReserve,
+			&service.MemoryReserve, &service.StaticBuildCmd, &service.StaticDir,
+			&service.CreatedAt, &service.UpdatedAt,
 		)
 
 		rollbackReq := CreateDeploymentRequest{
@@ -863,3 +904,35 @@ func handleRollbackDeployment(c *gin.Context) {
 		"message": "Rollback initiated",
 	})
 }
+
+// capacityCheck compares the requested per-replica memory (limit, falling
+// back to reservation) against node capacity. app_settings.capacity_policy
+// = "block" fails the deployment; the default "warn" only logs. CPU is not
+// gated — shares are a weight, not a reservation.
+func capacityCheck(ctx context.Context, db *database.DB, client *docker.Client, service Service, replicas int) string {
+	if client == nil {
+		return ""
+	}
+	requested := parseMemoryLimit(service.Memory)
+	if requested == 0 {
+		requested = parseMemoryLimit(service.MemoryReserve)
+	}
+	if requested == 0 {
+		return ""
+	}
+	info, err := client.GetSystemInfo(ctx)
+	if err != nil || info.MemTotal <= 0 {
+		return ""
+	}
+	need := requested * int64(replicas)
+	if need <= info.MemTotal {
+		return ""
+	}
+	msg := fmt.Sprintf("requested %d bytes x %d replicas exceeds node memory (%d bytes)",
+		requested, replicas, info.MemTotal)
+	if strings.ToLower(settingValue(db, "capacity_policy", "", "warn")) == "block" {
+		return msg
+	}
+	slog.Warn("capacity check exceeded", "service_id", service.ID, "detail", msg)
+	return ""
+}

app/backend/internal/api/resources_test.go

@@ -0,0 +1,48 @@
+package api
+
+import "testing"
+
+func TestParseCPUReserveShares(t *testing.T) {
+	cases := map[string]int64{
+		"":      0,
+		"0":     0,
+		"-1":    0,
+		"abc":   0,
+		"0.25":  256,
+		"1":     1024,
+		"2.5":   2560,
+		" 0.5 ": 512,
+	}
+	for in, want := range cases {
+		if got := parseCPUReserveShares(in); got != want {
+			t.Errorf("parseCPUReserveShares(%q) = %d, want %d", in, got, want)
+		}
+	}
+}
+
+func TestValidateResourceSpecs(t *testing.T) {
+	if err := validateCPUSpec(""); err != nil {
+		t.Error("empty cpu should pass")
+	}
+	if err := validateCPUSpec("0.5"); err != nil {
+		t.Error("0.5 should be valid cpu")
+	}
+	if err := validateCPUSpec("512mb"); err == nil {
+		t.Error("512mb should fail cpu validation")
+	}
+	if err := validateMemorySpec(""); err != nil {
+		t.Error("empty memory should pass")
+	}
+	if err := validateMemorySpec("512Mi"); err != nil {
+		t.Error("512Mi should be valid memory")
+	}
+	if err := validateMemorySpec("1g"); err != nil {
+		t.Error("1g should be valid memory")
+	}
+	if err := validateMemorySpec("0.5"); err == nil {
+		t.Error("0.5 should fail memory validation (parses to <1 byte)")
+	}
+	if err := validateMemorySpec("lots"); err == nil {
+		t.Error("'lots' should fail memory validation")
+	}
+}

app/backend/internal/api/runtime.go

@@ -53,6 +53,13 @@ func serviceRuntimeSpec(db *database.DB, service Service) (deployment.RuntimeSpe
 	}
 	spec.NanoCPUs = parseCPULimit(service.CPU)
 	spec.MemoryBytes = parseMemoryLimit(service.Memory)
+	spec.MemoryReserve = parseMemoryLimit(service.MemoryReserve)
+	spec.CPUShares = parseCPUReserveShares(service.CPUReserve)
+	if service.Builder == "static" && spec.Port == 0 {
+		// The static builder's image is nginx; expose its default port so
+		// Traefik has something to route to without extra config.
+		spec.Port = 80
+	}
 	spec.Volumes = loadServiceVolumes(db, service.ID)
 	spec.Domains = serviceDomainNames(db, service.ID, service.Domain)
 	spec.Maintenance, spec.BasicAuthUsers = serviceAccess(db, service.ID)
@@ -160,6 +167,32 @@ func parseCPULimit(cpu string) int64 {
 	return int64(v * 1e9)
 }
 
+// parseCPUReserveShares maps a cpu fraction to Docker's relative share
+// weight: 1024 shares ≈ one CPU.
+func parseCPUReserveShares(cpu string) int64 {
+	v, err := strconv.ParseFloat(strings.TrimSpace(cpu), 64)
+	if err != nil || v <= 0 {
+		return 0
+	}
+	return int64(v * 1024)
+}
+
+// validateCPUSpec and validateMemorySpec reject values that silently parse
+// to zero — a typo like "512mb" must fail loudly instead of dropping the limit.
+func validateCPUSpec(v string) error {
+	if s := strings.TrimSpace(v); s != "" && parseCPULimit(s) <= 0 {
+		return fmt.Errorf("must be a positive cpu fraction (e.g. 0.5, 2)")
+	}
+	return nil
+}
+
+func validateMemorySpec(v string) error {
+	if s := strings.TrimSpace(v); s != "" && parseMemoryLimit(s) <= 0 {
+		return fmt.Errorf("must be bytes with unit (e.g. 256Mi, 1g)")
+	}
+	return nil
+}
+
 var memUnits = map[string]int64{"k": 1e3, "m": 1e6, "g": 1e9, "ki": 1 << 10, "mi": 1 << 20, "gi": 1 << 30}
 
 func parseMemoryLimit(mem string) int64 {
@@ -215,6 +248,9 @@ func loadOwnedService(c *gin.Context, db *database.DB) (Service, bool) {
 		        COALESCE(s.replicas, 1), COALESCE(s.port, 0),
 		        COALESCE(s.domain, ''), COALESCE(s.healthcheck_path, ''),
 		        COALESCE(s.restart_policy, 'unless-stopped'),
+		        COALESCE(s.builder, 'auto'), COALESCE(s.cpu_reserve, ''),
+		        COALESCE(s.memory_reserve, ''), COALESCE(s.static_build_cmd, ''),
+		        COALESCE(s.static_dir, ''),
 		        s.created_at, s.updated_at, p.owner_id
 		 FROM services s JOIN projects p ON s.project_id = p.id
 		 WHERE s.id = $1`,
@@ -224,7 +260,9 @@ func loadOwnedService(c *gin.Context, db *database.DB) (Service, bool) {
 		&service.Image, &service.Command, &service.Environment, &service.GitRepo,
 		&service.GitBranch, &service.BuildPath, &service.CPU, &service.Memory,
 		&service.Replicas, &service.Port, &service.Domain, &service.HealthCheckPath,
-		&service.RestartPolicy, &service.CreatedAt, &service.UpdatedAt, &owner,
+		&service.RestartPolicy, &service.Builder, &service.CPUReserve,
+		&service.MemoryReserve, &service.StaticBuildCmd, &service.StaticDir,
+		&service.CreatedAt, &service.UpdatedAt, &owner,
 	)
 	if err != nil {
 		c.JSON(http.StatusNotFound, gin.H{"error": "Service not found"})
@@ -258,6 +296,9 @@ func loadReadableService(c *gin.Context, db *database.DB) (Service, bool) {
 		        COALESCE(s.replicas, 1), COALESCE(s.port, 0),
 		        COALESCE(s.domain, ''), COALESCE(s.healthcheck_path, ''),
 		        COALESCE(s.restart_policy, 'unless-stopped'),
+		        COALESCE(s.builder, 'auto'), COALESCE(s.cpu_reserve, ''),
+		        COALESCE(s.memory_reserve, ''), COALESCE(s.static_build_cmd, ''),
+		        COALESCE(s.static_dir, ''),
 		        s.created_at, s.updated_at, s.project_id
 		 FROM services s
 		 WHERE s.id = $1`,
@@ -267,7 +308,9 @@ func loadReadableService(c *gin.Context, db *database.DB) (Service, bool) {
 		&service.Image, &service.Command, &service.Environment, &service.GitRepo,
 		&service.GitBranch, &service.BuildPath, &service.CPU, &service.Memory,
 		&service.Replicas, &service.Port, &service.Domain, &service.HealthCheckPath,
-		&service.RestartPolicy, &service.CreatedAt, &service.UpdatedAt, &projectID,
+		&service.RestartPolicy, &service.Builder, &service.CPUReserve,
+		&service.MemoryReserve, &service.StaticBuildCmd, &service.StaticDir,
+		&service.CreatedAt, &service.UpdatedAt, &projectID,
 	)
 	if err != nil {
 		c.JSON(http.StatusNotFound, gin.H{"error": "Service not found"})
@@ -549,6 +592,9 @@ func runtimeScaleService(c *gin.Context, serviceID string, replicas int) error {
 		        COALESCE(s.replicas, 1), COALESCE(s.port, 0),
 		        COALESCE(s.domain, ''), COALESCE(s.healthcheck_path, ''),
 		        COALESCE(s.restart_policy, 'unless-stopped'),
+		        COALESCE(s.builder, 'auto'), COALESCE(s.cpu_reserve, ''),
+		        COALESCE(s.memory_reserve, ''), COALESCE(s.static_build_cmd, ''),
+		        COALESCE(s.static_dir, ''),
 		        s.created_at, s.updated_at, p.owner_id
 		 FROM services s JOIN projects p ON s.project_id = p.id
 		 WHERE s.id = $1`, serviceID,
@@ -557,7 +603,9 @@ func runtimeScaleService(c *gin.Context, serviceID string, replicas int) error {
 		&service.Image, &service.Command, &service.Environment, &service.GitRepo,
 		&service.GitBranch, &service.BuildPath, &service.CPU, &service.Memory,
 		&service.Replicas, &service.Port, &service.Domain, &service.HealthCheckPath,
-		&service.RestartPolicy, &service.CreatedAt, &service.UpdatedAt, &owner,
+		&service.RestartPolicy, &service.Builder, &service.CPUReserve,
+		&service.MemoryReserve, &service.StaticBuildCmd, &service.StaticDir,
+		&service.CreatedAt, &service.UpdatedAt, &owner,
 	)
 	if err != nil {
 		return err

app/backend/internal/api/services.go

@@ -41,6 +41,11 @@ type Service struct {
 	Domains         []ServiceDomain `json:"domains,omitempty" db:"-"`
 	MaintenanceMode bool            `json:"maintenance_mode" db:"-"`
 	BasicAuth       []string        `json:"basic_auth,omitempty" db:"-"` // usernames only, never hashes
+	Builder         string          `json:"builder" db:"builder"`        // auto|railpack|nixpacks|dockerfile|static
+	CPUReserve      string          `json:"cpu_reserve,omitempty" db:"cpu_reserve"`
+	MemoryReserve   string          `json:"memory_reserve,omitempty" db:"memory_reserve"`
+	StaticBuildCmd  string          `json:"static_build_cmd,omitempty" db:"static_build_cmd"`
+	StaticDir       string          `json:"static_dir,omitempty" db:"static_dir"`
 	CreatedAt       time.Time       `json:"created_at" db:"created_at"`
 	UpdatedAt       time.Time       `json:"updated_at" db:"updated_at"`
 }
@@ -117,6 +122,11 @@ type CreateServiceRequest struct {
 	Volumes         []ServiceVolume `json:"volumes"`
 	MaintenanceMode bool            `json:"maintenance_mode"`
 	BasicAuth       []BasicAuthCred `json:"basic_auth"`
+	Builder         string          `json:"builder" binding:"omitempty,oneof=auto railpack nixpacks dockerfile static"`
+	CPUReserve      string          `json:"cpu_reserve"`
+	MemoryReserve   string          `json:"memory_reserve"`
+	StaticBuildCmd  string          `json:"static_build_cmd"`
+	StaticDir       string          `json:"static_dir"`
 }
 
 // UpdateServiceRequest represents a request to update a service
@@ -139,6 +149,11 @@ type UpdateServiceRequest struct {
 	Volumes         *[]ServiceVolume `json:"volumes"`
 	MaintenanceMode *bool            `json:"maintenance_mode"`
 	BasicAuth       *[]BasicAuthCred `json:"basic_auth"`
+	Builder         string           `json:"builder" binding:"omitempty,oneof=auto railpack nixpacks dockerfile static"`
+	CPUReserve      *string          `json:"cpu_reserve"`
+	MemoryReserve   *string          `json:"memory_reserve"`
+	StaticBuildCmd  *string          `json:"static_build_cmd"`
+	StaticDir       *string          `json:"static_dir"`
 }
 
 // handleGetServices retrieves all services for a project
@@ -183,6 +198,9 @@ func handleGetServices(c *gin.Context) {
 				COALESCE(replicas, 1), COALESCE(port, 0),
 				COALESCE(domain, ''), COALESCE(healthcheck_path, ''),
 				COALESCE(restart_policy, 'unless-stopped'),
+				COALESCE(builder, 'auto'), COALESCE(cpu_reserve, ''),
+				COALESCE(memory_reserve, ''), COALESCE(static_build_cmd, ''),
+				COALESCE(static_dir, ''),
 				created_at, updated_at 
 			FROM services 
 			WHERE project_id = $1 
@@ -203,7 +221,9 @@ func handleGetServices(c *gin.Context) {
 			&service.Image, &service.Command, &service.Environment, &service.GitRepo,
 			&service.GitBranch, &service.BuildPath, &service.CPU, &service.Memory,
 			&service.Replicas, &service.Port, &service.Domain, &service.HealthCheckPath,
-			&service.RestartPolicy, &service.CreatedAt, &service.UpdatedAt,
+			&service.RestartPolicy, &service.Builder, &service.CPUReserve,
+			&service.MemoryReserve, &service.StaticBuildCmd, &service.StaticDir,
+			&service.CreatedAt, &service.UpdatedAt,
 		)
 		if err != nil {
 			c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to scan service"})
@@ -314,12 +334,38 @@ func handleCreateService(c *gin.Context) {
 		UpdatedAt:       time.Now(),
 	}
 
-	// Set default values if not provided
+	// Set default values if not provided; app_settings.default_cpu /
+	// default_memory override the hardcoded fallbacks.
 	if service.CPU == "" {
-		service.CPU = "0.5"
+		service.CPU = firstNonEmpty(settingValue(db.(*database.DB), "default_cpu", "", ""), "0.5")
 	}
 	if service.Memory == "" {
-		service.Memory = "512Mi"
+		service.Memory = firstNonEmpty(settingValue(db.(*database.DB), "default_memory", "", ""), "512Mi")
+	}
+	if req.Builder == "" {
+		service.Builder = "auto"
+	} else {
+		service.Builder = req.Builder
+	}
+	service.CPUReserve = req.CPUReserve
+	service.MemoryReserve = req.MemoryReserve
+	service.StaticBuildCmd = req.StaticBuildCmd
+	service.StaticDir = req.StaticDir
+	if service.Builder == "static" && service.StaticDir == "" {
+		service.StaticDir = "dist"
+	}
+	for label, check := range map[string]func(string) error{
+		"cpu": validateCPUSpec, "cpu_reserve": validateCPUSpec,
+		"memory": validateMemorySpec, "memory_reserve": validateMemorySpec,
+	} {
+		v := map[string]string{
+			"cpu": service.CPU, "cpu_reserve": service.CPUReserve,
+			"memory": service.Memory, "memory_reserve": service.MemoryReserve,
+		}[label]
+		if err := check(v); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("invalid %s: %s", label, err.Error()), "code": "VALIDATION"})
+			return
+		}
 	}
 	if service.Replicas < 1 {
 		service.Replicas = 1
@@ -351,14 +397,18 @@ func handleCreateService(c *gin.Context) {
 			(id, project_id, name, environment_id, service_type, source_type, source_url, image_name,
 				 build_command, start_command, type, status, image, command, environment,
 				 git_repo, git_branch, build_path, cpu, memory, replicas, port, domain,
-				 healthcheck_path, restart_policy, volumes, created_at, updated_at)
-			VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18, $19, $20, $21, $22, $23, $24, $25, $26, $27, $28)`,
+				 healthcheck_path, restart_policy, volumes,
+				 builder, cpu_reserve, memory_reserve, static_build_cmd, static_dir,
+				 created_at, updated_at)
+			VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18, $19, $20, $21, $22, $23, $24, $25, $26,
+					$27, $28, $29, $30, $31, $32, $33)`,
 		service.ID, service.ProjectID, service.Name, environmentID, service.Type,
 		sourceType, firstNonEmpty(service.GitRepo, service.Image), service.Image,
 		"", service.Command, service.Type, service.Status, service.Image, service.Command,
 		service.Environment, service.GitRepo, service.GitBranch, service.BuildPath, service.CPU, service.Memory,
 		service.Replicas, service.Port, service.Domain, service.HealthCheckPath, service.RestartPolicy,
-		volumesJSON, service.CreatedAt, service.UpdatedAt,
+		volumesJSON, service.Builder, service.CPUReserve, service.MemoryReserve,
+		service.StaticBuildCmd, service.StaticDir, service.CreatedAt, service.UpdatedAt,
 	)
 
 	if err != nil {
@@ -443,6 +493,9 @@ func handleGetService(c *gin.Context) {
 				COALESCE(s.replicas, 1), COALESCE(s.port, 0),
 				COALESCE(s.domain, ''), COALESCE(s.healthcheck_path, ''),
 				COALESCE(s.restart_policy, 'unless-stopped'),
+				COALESCE(s.builder, 'auto'), COALESCE(s.cpu_reserve, ''),
+				COALESCE(s.memory_reserve, ''), COALESCE(s.static_build_cmd, ''),
+				COALESCE(s.static_dir, ''),
 				s.created_at, s.updated_at
 			FROM services s
 			JOIN projects p ON s.project_id = p.id
@@ -454,7 +507,9 @@ func handleGetService(c *gin.Context) {
 		&service.Image, &service.Command, &service.Environment, &service.GitRepo,
 		&service.GitBranch, &service.BuildPath, &service.CPU, &service.Memory,
 		&service.Replicas, &service.Port, &service.Domain, &service.HealthCheckPath,
-		&service.RestartPolicy, &service.CreatedAt, &service.UpdatedAt,
+		&service.RestartPolicy, &service.Builder, &service.CPUReserve,
+		&service.MemoryReserve, &service.StaticBuildCmd, &service.StaticDir,
+		&service.CreatedAt, &service.UpdatedAt,
 	)
 
 	if err != nil {
@@ -520,6 +575,9 @@ func handleUpdateService(c *gin.Context) {
 				COALESCE(s.replicas, 1), COALESCE(s.port, 0),
 				COALESCE(s.domain, ''), COALESCE(s.healthcheck_path, ''),
 				COALESCE(s.restart_policy, 'unless-stopped'),
+				COALESCE(s.builder, 'auto'), COALESCE(s.cpu_reserve, ''),
+				COALESCE(s.memory_reserve, ''), COALESCE(s.static_build_cmd, ''),
+				COALESCE(s.static_dir, ''),
 				s.created_at, s.updated_at
 			FROM services s
 			JOIN projects p ON s.project_id = p.id
@@ -532,6 +590,9 @@ func handleUpdateService(c *gin.Context) {
 		&existingService.BuildPath, &existingService.CPU, &existingService.Memory,
 		&existingService.Replicas, &existingService.Port, &existingService.Domain,
 		&existingService.HealthCheckPath, &existingService.RestartPolicy,
+		&existingService.Builder, &existingService.CPUReserve,
+		&existingService.MemoryReserve, &existingService.StaticBuildCmd,
+		&existingService.StaticDir,
 		&existingService.CreatedAt, &existingService.UpdatedAt,
 	)
 
@@ -586,6 +647,37 @@ func handleUpdateService(c *gin.Context) {
 	if req.RestartPolicy != "" {
 		existingService.RestartPolicy = req.RestartPolicy
 	}
+	if req.Builder != "" {
+		existingService.Builder = req.Builder
+	}
+	if req.CPUReserve != nil {
+		existingService.CPUReserve = *req.CPUReserve
+	}
+	if req.MemoryReserve != nil {
+		existingService.MemoryReserve = *req.MemoryReserve
+	}
+	if req.StaticBuildCmd != nil {
+		existingService.StaticBuildCmd = *req.StaticBuildCmd
+	}
+	if req.StaticDir != nil {
+		existingService.StaticDir = *req.StaticDir
+	}
+	if existingService.Builder == "static" && existingService.StaticDir == "" {
+		existingService.StaticDir = "dist"
+	}
+	for label, check := range map[string]func(string) error{
+		"cpu": validateCPUSpec, "cpu_reserve": validateCPUSpec,
+		"memory": validateMemorySpec, "memory_reserve": validateMemorySpec,
+	} {
+		v := map[string]string{
+			"cpu": existingService.CPU, "cpu_reserve": existingService.CPUReserve,
+			"memory": existingService.Memory, "memory_reserve": existingService.MemoryReserve,
+		}[label]
+		if err := check(v); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("invalid %s: %s", label, err.Error()), "code": "VALIDATION"})
+			return
+		}
+	}
 	// lib/pq sends a nil []byte as an empty bytea literal rather than NULL,
 	// so the COALESCE fallback needs an untyped nil when volumes aren't sent.
 	var volumesArg interface{}
@@ -607,7 +699,9 @@ func handleUpdateService(c *gin.Context) {
 			SET name = $1, type = $2, image = $3, command = $4, environment = $5,
 				git_repo = $6, git_branch = $7, build_path = $8, cpu = $9, memory = $10,
 				replicas = $11, port = $12, domain = $13, healthcheck_path = $14,
-				restart_policy = $15, volumes = COALESCE($17::jsonb, volumes), updated_at = $16
+				restart_policy = $15, volumes = COALESCE($17::jsonb, volumes), updated_at = $16,
+				builder = $19, cpu_reserve = $20, memory_reserve = $21,
+				static_build_cmd = $22, static_dir = $23
 			WHERE id = $18`,
 		existingService.Name, existingService.Type, existingService.Image, existingService.Command,
 		existingService.Environment, existingService.GitRepo, existingService.GitBranch,
@@ -615,6 +709,8 @@ func handleUpdateService(c *gin.Context) {
 		existingService.Replicas, existingService.Port, existingService.Domain,
 		existingService.HealthCheckPath, existingService.RestartPolicy,
 		existingService.UpdatedAt, volumesArg, existingService.ID,
+		existingService.Builder, existingService.CPUReserve, existingService.MemoryReserve,
+		existingService.StaticBuildCmd, existingService.StaticDir,
 	)
 
 	if err != nil {

app/backend/internal/api/variables.go

@@ -218,12 +218,14 @@ func handleUpdateVariables(c *gin.Context) {
 			`SELECT id, project_id, name, COALESCE(image, ''), COALESCE(command, ''),
 			        COALESCE(replicas, 1), COALESCE(port, 0), COALESCE(domain, ''),
 			        COALESCE(healthcheck_path, ''), COALESCE(restart_policy, 'unless-stopped'),
-			        COALESCE(cpu, ''), COALESCE(memory, '')
+			        COALESCE(cpu, ''), COALESCE(memory, ''),
+			        COALESCE(builder, 'auto'), COALESCE(cpu_reserve, ''), COALESCE(memory_reserve, '')
 			 FROM services WHERE id = $1`,
 			serviceID,
 		).Scan(&svc.ID, &svc.ProjectID, &svc.Name, &svc.Image, &svc.Command,
 			&svc.Replicas, &svc.Port, &svc.Domain, &svc.HealthCheckPath,
-			&svc.RestartPolicy, &svc.CPU, &svc.Memory)
+			&svc.RestartPolicy, &svc.CPU, &svc.Memory,
+			&svc.Builder, &svc.CPUReserve, &svc.MemoryReserve)
 		resp["redeploy_queued"] = svcErr == nil && enqueueServiceRedeploy(c, db.(*database.DB), svc)
 	}
 	c.JSON(http.StatusOK, resp)

app/backend/internal/build/dockerfile.go

@@ -211,8 +211,12 @@ func (d *DockerfileBuilder) Build(ctx context.Context, req *types.BuildRequest)
 	// Build Docker image
 	imageName := fmt.Sprintf("%s:%s", req.ImageName, req.ImageTag)
 
-	// Create build context tar
-	buildCtx, err := createBuildContext(req.SourcePath, optimizedDockerfile)
+	// createBuildContext wants the Dockerfile contents, not its path.
+	dockerfileContent, err := os.ReadFile(optimizedDockerfile)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read Dockerfile: %w", err)
+	}
+	buildCtx, err := createBuildContext(req.SourcePath, string(dockerfileContent))
 	if err != nil {
 		return nil, fmt.Errorf("failed to create build context: %w", err)
 	}

app/backend/internal/build/manager.go

@@ -16,6 +16,7 @@ type BuildManager struct {
 	railpackBuilder   *RailpackBuilder
 	nixpacksBuilder   *NixpacksBuilder
 	dockerfileBuilder *DockerfileBuilder
+	staticBuilder     *StaticBuilder
 	dockerClient      *docker.Client
 	cacheManager      *CacheManager
 	parallelBuilder   *ParallelBuilder
@@ -28,6 +29,7 @@ const (
 	BuildTypeRailpack   BuildType = "railpack"
 	BuildTypeNixpacks   BuildType = "nixpacks"
 	BuildTypeDockerfile BuildType = "dockerfile"
+	BuildTypeStatic     BuildType = "static"
 	BuildTypePrebuilt   BuildType = "prebuilt"
 )
 
@@ -39,6 +41,7 @@ func NewBuildManager(workDir string, dockerClient *docker.Client) *BuildManager
 		railpackBuilder:   NewRailpackBuilder(workDir, dockerClient),
 		nixpacksBuilder:   NewNixpacksBuilder(workDir, dockerClient),
 		dockerfileBuilder: NewDockerfileBuilder(workDir, dockerClient),
+		staticBuilder:     NewStaticBuilder(dockerClient),
 		dockerClient:      dockerClient,
 		cacheManager:      cacheManager,
 		parallelBuilder:   parallelBuilder,
@@ -80,6 +83,8 @@ func (bm *BuildManager) Build(ctx context.Context, req *types.BuildRequest) (*ty
 		return bm.nixpacksBuilder.Build(ctx, req)
 	case BuildTypeDockerfile:
 		return bm.dockerfileBuilder.Build(ctx, req)
+	case BuildTypeStatic:
+		return bm.staticBuilder.Build(ctx, req)
 	case BuildTypePrebuilt:
 		return bm.buildPrebuilt(ctx, req)
 	default:

app/backend/internal/build/static.go

@@ -0,0 +1,95 @@
+package build
+
+import (
+	"context"
+	"fmt"
+
+	"containr/internal/docker"
+	"containr/internal/types"
+)
+
+// StaticBuilder produces an nginx-served image from a repo's built assets.
+// STATIC_BUILD_CMD runs inside a node build stage; STATIC_DIR names the
+// output directory copied into the nginx image. Both are overridable via
+// build args so repos with non-node toolchains can swap the build image too.
+type StaticBuilder struct {
+	dockerClient *docker.Client
+}
+
+func NewStaticBuilder(dockerClient *docker.Client) *StaticBuilder {
+	return &StaticBuilder{dockerClient: dockerClient}
+}
+
+const staticDockerfile = `ARG BUILD_IMAGE=node:20-alpine
+FROM ${BUILD_IMAGE} AS assets
+WORKDIR /app
+COPY . .
+ARG STATIC_BUILD_CMD
+RUN sh -c "${STATIC_BUILD_CMD}"
+
+FROM nginx:alpine
+ARG STATIC_DIR=dist
+COPY --from=assets /app/${STATIC_DIR} /usr/share/nginx/html
+EXPOSE 80
+CMD ["nginx", "-g", "daemon off;"]
+`
+
+func (s *StaticBuilder) Build(ctx context.Context, req *types.BuildRequest) (*types.BuildResponse, error) {
+	buildCmd := req.BuildCommand
+	if buildCmd == "" {
+		buildCmd = "npm ci && npm run build"
+	}
+	staticDir := req.BuildArgs["STATIC_DIR"]
+	if staticDir == "" {
+		staticDir = "dist"
+	}
+
+	buildArgs := map[string]*string{}
+	for k, v := range req.BuildArgs {
+		v := v
+		buildArgs[k] = &v
+	}
+	for k, v := range req.Environment {
+		v := v
+		buildArgs[k] = &v
+	}
+	buildArgs["STATIC_BUILD_CMD"] = &buildCmd
+	buildArgs["STATIC_DIR"] = &staticDir
+
+	imageName := fmt.Sprintf("%s:%s", req.ImageName, req.ImageTag)
+	buildCtx, err := createBuildContext(req.SourcePath, staticDockerfile)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create build context: %w", err)
+	}
+	defer buildCtx.Close()
+
+	if _, err := s.dockerClient.BuildImage(ctx, buildCtx, docker.BuildOptions{
+		Dockerfile: "Dockerfile",
+		Tags:       []string{imageName},
+		BuildArgs:  buildArgs,
+		NoCache:    req.NoCache,
+		Remove:     true,
+	}); err != nil {
+		return nil, fmt.Errorf("failed to build static image: %w", err)
+	}
+
+	if req.RegistryURL != "" {
+		full := fmt.Sprintf("%s/%s", req.RegistryURL, imageName)
+		if err := s.dockerClient.PushImage(ctx, imageName, req.RegistryURL); err != nil {
+			return nil, fmt.Errorf("failed to push image: %w", err)
+		}
+		imageName = full
+	}
+
+	imageInfo, err := s.dockerClient.GetImageInfo(ctx, imageName)
+	if err != nil {
+		imageInfo = &docker.ImageInfo{Size: 0}
+	}
+
+	return &types.BuildResponse{
+		ImageName: imageName,
+		ImageTag:  req.ImageTag,
+		Size:      imageInfo.Size,
+		Digest:    imageInfo.Digest,
+	}, nil
+}

app/backend/internal/cli/commands/services.go

@@ -79,7 +79,7 @@ var servicesCreateCmd = &cobra.Command{
 		body := map[string]interface{}{
 			"name": args[1],
 		}
-		for _, f := range []string{"type", "image", "git-repo", "git-branch", "build-path", "command", "environment", "domain", "restart-policy", "healthcheck-path", "cpu", "memory"} {
+		for _, f := range []string{"type", "image", "git-repo", "git-branch", "build-path", "command", "environment", "domain", "restart-policy", "healthcheck-path", "cpu", "memory", "builder", "cpu-reserve", "memory-reserve", "static-cmd", "static-dir"} {
 			if v, _ := cmd.Flags().GetString(f); v != "" {
 				key := f
 				// JSON uses snake_case keys matching the API schema.
@@ -94,6 +94,14 @@ var servicesCreateCmd = &cobra.Command{
 					key = "restart_policy"
 				case "healthcheck-path":
 					key = "healthcheck_path"
+				case "cpu-reserve":
+					key = "cpu_reserve"
+				case "memory-reserve":
+					key = "memory_reserve"
+				case "static-cmd":
+					key = "static_build_cmd"
+				case "static-dir":
+					key = "static_dir"
 				}
 				body[key] = v
 			}
@@ -151,7 +159,7 @@ var servicesUpdateCmd = &cobra.Command{
 			return err
 		}
 		body := map[string]interface{}{}
-		for _, f := range []string{"name", "image", "command", "domain", "restart-policy", "healthcheck-path", "cpu", "memory"} {
+		for _, f := range []string{"name", "image", "command", "domain", "restart-policy", "healthcheck-path", "cpu", "memory", "builder", "cpu-reserve", "memory-reserve", "static-cmd", "static-dir"} {
 			if cmd.Flags().Changed(f) {
 				key := f
 				switch f {
@@ -159,6 +167,14 @@ var servicesUpdateCmd = &cobra.Command{
 					key = "restart_policy"
 				case "healthcheck-path":
 					key = "healthcheck_path"
+				case "cpu-reserve":
+					key = "cpu_reserve"
+				case "memory-reserve":
+					key = "memory_reserve"
+				case "static-cmd":
+					key = "static_build_cmd"
+				case "static-dir":
+					key = "static_dir"
 				}
 				v, _ := cmd.Flags().GetString(f)
 				body[key] = v
@@ -406,6 +422,11 @@ func init() {
 	f.String("memory", "", "memory limit (e.g. 512m)")
 	f.Int("port", 0, "container port")
 	f.Int("replicas", 0, "replica count")
+	f.String("builder", "", "build strategy: auto|railpack|nixpacks|dockerfile|static")
+	f.String("cpu-reserve", "", "soft CPU reservation (e.g. 0.25)")
+	f.String("memory-reserve", "", "soft memory reservation (e.g. 128Mi)")
+	f.String("static-cmd", "", "build command for the static builder")
+	f.String("static-dir", "", "output dir for the static builder (default dist)")
 
 	uf := servicesUpdateCmd.Flags()
 	uf.String("name", "", "service name")
@@ -423,6 +444,11 @@ func init() {
 	uf.Bool("clear-volumes", false, "remove all volume mounts")
 	uf.String("maintenance", "", "maintenance mode: on|off")
 	uf.StringArray("basic-auth", nil, "basic-auth credential user:password (repeatable, replaces all)")
+	uf.String("builder", "", "build strategy: auto|railpack|nixpacks|dockerfile|static")
+	uf.String("cpu-reserve", "", "soft CPU reservation (empty clears)")
+	uf.String("memory-reserve", "", "soft memory reservation (empty clears)")
+	uf.String("static-cmd", "", "build command for the static builder (empty clears)")
+	uf.String("static-dir", "", "output dir for the static builder (empty clears)")
 
 	for _, a := range []string{"start", "stop", "restart", "redeploy"} {
 		verb := a

app/backend/internal/deployment/engine.go

@@ -84,10 +84,11 @@ type VolumeMount struct {
 }
 
 type ResourceLimits struct {
-	MemoryBytes int64 `json:"memory_bytes,omitempty"`
-	CPUQuota    int64 `json:"cpu_quota,omitempty"`
-	CPUPeriod   int64 `json:"cpu_period,omitempty"`
-	CPUShares   int64 `json:"cpu_shares,omitempty"`
+	MemoryBytes       int64 `json:"memory_bytes,omitempty"`
+	MemoryReservation int64 `json:"memory_reservation,omitempty"`
+	CPUQuota          int64 `json:"cpu_quota,omitempty"`
+	CPUPeriod         int64 `json:"cpu_period,omitempty"`
+	CPUShares         int64 `json:"cpu_shares,omitempty"`
 }
 
 type HealthCheck struct {
@@ -152,6 +153,7 @@ type BuildConfig struct {
 	PrebuiltImage string            `json:"prebuilt_image"`
 	BuildCommand  string            `json:"build_command"`
 	StartCommand  string            `json:"start_command"`
+	BuildArgs     map[string]string `json:"build_args,omitempty"`
 	Environment   map[string]string `json:"environment"`
 	Branch        string            `json:"branch"`
 	Commit        string            `json:"commit"`
@@ -166,6 +168,12 @@ type TriggerConfig struct {
 	Timestamp time.Time         `json:"timestamp"` // When trigger occurred
 }
 
+// DockerClient exposes the engine's docker handle for read-only queries
+// (capacity checks, image info).
+func (de *DeploymentEngine) DockerClient() *docker.Client {
+	return de.dockerClient
+}
+
 func NewDeploymentEngine(buildManager *build.BuildManager, dockerClient *docker.Client) *DeploymentEngine {
 	return &DeploymentEngine{
 		buildManager:  buildManager,
@@ -290,6 +298,7 @@ func (de *DeploymentEngine) buildImage(ctx context.Context, deployment *Deployme
 		ImageTag:      deployment.ID,
 		BuildCommand:  buildConfig.BuildCommand,
 		StartCommand:  buildConfig.StartCommand,
+		BuildArgs:     buildConfig.BuildArgs,
 		Environment:   buildConfig.Environment,
 		ProjectID:     deployment.ProjectID,
 		ServiceID:     deployment.ServiceID,
@@ -330,7 +339,9 @@ func (de *DeploymentEngine) deployService(ctx context.Context, deployment *Deplo
 		HealthPath:     cfg.HealthPath,
 		RestartPolicy:  cfg.RestartPolicy,
 		MemoryBytes:    cfg.Resources.MemoryBytes,
+		MemoryReserve:  cfg.Resources.MemoryReservation,
 		NanoCPUs:       cfg.Resources.CPUQuota,
+		CPUShares:      cfg.Resources.CPUShares,
 		Volumes:        cfg.VolumeMounts,
 		Domains:        cfg.Domains,
 		Maintenance:    cfg.Maintenance,

app/backend/internal/deployment/runtime.go

@@ -47,7 +47,9 @@ type RuntimeSpec struct {
 	HealthPath     string // http path probed on Port for container healthcheck
 	RestartPolicy  string
 	MemoryBytes    int64
+	MemoryReserve  int64 // soft reservation; scheduler hint, not a hard cap
 	NanoCPUs       int64
+	CPUShares      int64         // relative weight (1024 ≈ 1 cpu), not a cap
 	Volumes        []VolumeMount // applied to every replica
 	Domains        []string      // all public hostnames; Domain is the default
 	Maintenance    bool          // redirect traffic to MaintenanceURL
@@ -273,15 +275,17 @@ func (de *DeploymentEngine) createReplica(ctx context.Context, spec RuntimeSpec,
 	}
 
 	cfg := docker.ContainerConfig{
-		Name:          fmt.Sprintf("%s%d", serviceNamePrefix(spec.ServiceID), index),
-		Image:         spec.Image,
-		Cmd:           spec.Command,
-		Env:           env,
-		Labels:        labels,
-		RestartPolicy: spec.RestartPolicy,
-		Memory:        spec.MemoryBytes,
-		NanoCPUs:      spec.NanoCPUs,
-		Networks:      endpoints,
+		Name:              fmt.Sprintf("%s%d", serviceNamePrefix(spec.ServiceID), index),
+		Image:             spec.Image,
+		Cmd:               spec.Command,
+		Env:               env,
+		Labels:            labels,
+		RestartPolicy:     spec.RestartPolicy,
+		Memory:            spec.MemoryBytes,
+		MemoryReservation: spec.MemoryReserve,
+		NanoCPUs:          spec.NanoCPUs,
+		CPUShares:         spec.CPUShares,
+		Networks:          endpoints,
 	}
 
 	for _, v := range spec.Volumes {
@@ -526,12 +530,14 @@ func specHash(spec RuntimeSpec) string {
 		Env                                            map[string]string
 		Port                                           int32
 		MemoryBytes, NanoCPUs                          int64
+		MemoryReserve, CPUShares                       int64
 		Volumes                                        []VolumeMount
 		Domains                                        []string
 		Maintenance                                    bool
 		BasicAuth                                      string
 	}{spec.Image, spec.Name, spec.Domain, spec.HealthPath, spec.RestartPolicy,
-		spec.Command, spec.Env, spec.Port, spec.MemoryBytes, spec.NanoCPUs, spec.Volumes,
+		spec.Command, spec.Env, spec.Port, spec.MemoryBytes, spec.NanoCPUs,
+		spec.MemoryReserve, spec.CPUShares, spec.Volumes,
 		spec.Domains, spec.Maintenance, spec.BasicAuthUsers})
 	sum := sha256.Sum256(payload)
 	return hex.EncodeToString(sum[:8])

app/backend/internal/docker/client.go

@@ -156,8 +156,10 @@ func (c *Client) CreateContainer(ctx context.Context, config ContainerConfig) (s
 		PortBindings: config.PortBindings,
 		Mounts:       config.Mounts,
 		Resources: container.Resources{
-			Memory:   config.Memory,
-			NanoCPUs: config.NanoCPUs,
+			Memory:            config.Memory,
+			MemoryReservation: config.MemoryReservation,
+			NanoCPUs:          config.NanoCPUs,
+			CPUShares:         config.CPUShares,
 		},
 		NetworkMode: container.NetworkMode(config.NetworkMode),
 	}
@@ -291,7 +293,7 @@ func (c *Client) PullImageWait(ctx context.Context, ref string, auth registry.Au
 
 // BuildImage builds an image from a Dockerfile
 func (c *Client) BuildImage(ctx context.Context, buildContext io.Reader, options BuildOptions) (types.ImageBuildResponse, error) {
-	return c.cli.ImageBuild(ctx, buildContext, types.ImageBuildOptions{
+	resp, err := c.cli.ImageBuild(ctx, buildContext, types.ImageBuildOptions{
 		Dockerfile: options.Dockerfile,
 		Tags:       options.Tags,
 		BuildArgs:  options.BuildArgs,
@@ -299,6 +301,34 @@ func (c *Client) BuildImage(ctx context.Context, buildContext io.Reader, options
 		Remove:     options.Remove,
 		NoCache:    options.NoCache,
 	})
+	if err != nil {
+		return resp, err
+	}
+	// The daemon aborts the build if the response stream isn't consumed,
+	// and reports failures only inside that stream.
+	defer resp.Body.Close()
+	var buildErr string
+	dec := json.NewDecoder(resp.Body)
+	for {
+		var line struct {
+			ErrorDetail struct {
+				Message string `json:"message"`
+			} `json:"errorDetail"`
+			Error string `json:"error"`
+		}
+		if err := dec.Decode(&line); err != nil {
+			break
+		}
+		if line.ErrorDetail.Message != "" {
+			buildErr = line.ErrorDetail.Message
+		} else if line.Error != "" {
+			buildErr = line.Error
+		}
+	}
+	if buildErr != "" {
+		return resp, fmt.Errorf("docker build failed: %s", buildErr)
+	}
+	return resp, nil
 }
 
 // RemoveImage removes an image

app/backend/internal/docker/types.go

@@ -12,20 +12,22 @@ import (
 
 // ContainerConfig represents the configuration for creating a container
 type ContainerConfig struct {
-	Name          string
-	Image         string
-	Cmd           []string
-	Env           []string
-	Labels        map[string]string
-	RestartPolicy string
-	ExposedPorts  nat.PortSet
-	PortBindings  nat.PortMap
-	Mounts        []mount.Mount
-	Memory        int64
-	NanoCPUs      int64
-	NetworkMode   string
-	Networks      map[string]*network.EndpointSettings
-	Healthcheck   *container.HealthConfig
+	Name              string
+	Image             string
+	Cmd               []string
+	Env               []string
+	Labels            map[string]string
+	RestartPolicy     string
+	ExposedPorts      nat.PortSet
+	PortBindings      nat.PortMap
+	Mounts            []mount.Mount
+	Memory            int64
+	MemoryReservation int64
+	NanoCPUs          int64
+	CPUShares         int64
+	NetworkMode       string
+	Networks          map[string]*network.EndpointSettings
+	Healthcheck       *container.HealthConfig
 }
 
 // LogOptions represents options for retrieving container logs

app/backend/internal/mcpserver/server.go

@@ -53,7 +53,7 @@ func init() {
 	// Services
 	register(spec{"containr_services_list", "List services in a project", "GET", "/projects/{project_id}/services", []string{"project_id"}, nil, false})
 	register(spec{"containr_services_get", "Get a service by id", "GET", "/services/{id}", []string{"id"}, nil, false})
-	register(spec{"containr_services_create", "Create a service in a project. Args: name (required), type, image, git_repo, git_branch, environment, port, domain, replicas, volumes = [{type: volume|bind, source, target, read_only}].", "POST", "/projects/{project_id}/services", []string{"project_id"}, nil, false})
+	register(spec{"containr_services_create", "Create a service in a project. Args: name (required), type, image, git_repo, git_branch, environment, port, domain, replicas, volumes = [{type: volume|bind, source, target, read_only}], builder = auto|railpack|nixpacks|dockerfile|static, cpu, memory, cpu_reserve, memory_reserve, static_build_cmd, static_dir.", "POST", "/projects/{project_id}/services", []string{"project_id"}, nil, false})
 	register(spec{"containr_services_delete", "Delete a service. Requires confirm:true.", "DELETE", "/services/{id}", []string{"id"}, nil, true})
 	register(spec{"containr_services_start", "Start a service", "POST", "/services/{id}/start", []string{"id"}, nil, false})
 	register(spec{"containr_services_stop", "Stop a service", "POST", "/services/{id}/stop", []string{"id"}, nil, false})
@@ -61,7 +61,7 @@ func init() {
 	register(spec{"containr_services_redeploy", "Rebuild and redeploy a service", "POST", "/services/{id}/redeploy", []string{"id"}, nil, false})
 	register(spec{"containr_services_logs", "Get service runtime logs. Args: id, tail (default 100).", "GET", "/services/{id}/logs", []string{"id"}, nil, false})
 	register(spec{"containr_services_exec", "Run a one-off command in the service container (30s ceiling). Args: id, command (required).", "POST", "/services/{id}/exec", []string{"id"}, []string{"command"}, false})
-	register(spec{"containr_services_update", "Update a service. Args: id, name, image, command, domain, restart_policy, healthcheck_path, cpu, memory, replicas, port, volumes = [{type: volume|bind, source, target, read_only}] — volumes replaces the whole mount list; pass [] to clear. maintenance_mode (bool), basic_auth = [{username, password}] — replaces all creds; [] clears.", "PUT", "/services/{id}", []string{"id"}, nil, false})
+	register(spec{"containr_services_update", "Update a service. Args: id, name, image, command, domain, restart_policy, healthcheck_path, cpu, memory, replicas, port, volumes = [{type: volume|bind, source, target, read_only}] — volumes replaces the whole mount list; pass [] to clear. maintenance_mode (bool), basic_auth = [{username, password}] — replaces all creds; [] clears. builder = auto|railpack|nixpacks|dockerfile|static, cpu_reserve, memory_reserve, static_build_cmd, static_dir (empty string clears reserves/static fields).", "PUT", "/services/{id}", []string{"id"}, nil, false})
 
 	// Domains
 	register(spec{"containr_domains_list", "List domains attached to a service", "GET", "/services/{id}/domains", []string{"id"}, nil, false})

app/backend/migrations_goose/20261011000000_builder_resources.sql

@@ -0,0 +1,17 @@
+-- +goose Up
+-- +goose StatementBegin
+ALTER TABLE services ADD COLUMN IF NOT EXISTS builder varchar(32) NOT NULL DEFAULT 'auto';
+ALTER TABLE services ADD COLUMN IF NOT EXISTS cpu_reserve varchar(20) NOT NULL DEFAULT '';
+ALTER TABLE services ADD COLUMN IF NOT EXISTS memory_reserve varchar(20) NOT NULL DEFAULT '';
+ALTER TABLE services ADD COLUMN IF NOT EXISTS static_build_cmd varchar(255) NOT NULL DEFAULT '';
+ALTER TABLE services ADD COLUMN IF NOT EXISTS static_dir varchar(255) NOT NULL DEFAULT '';
+-- +goose StatementEnd
+
+-- +goose Down
+-- +goose StatementBegin
+ALTER TABLE services DROP COLUMN IF EXISTS static_dir;
+ALTER TABLE services DROP COLUMN IF EXISTS static_build_cmd;
+ALTER TABLE services DROP COLUMN IF EXISTS memory_reserve;
+ALTER TABLE services DROP COLUMN IF EXISTS cpu_reserve;
+ALTER TABLE services DROP COLUMN IF EXISTS builder;
+-- +goose StatementEnd

app/backend/sqlc/schema.sql

@@ -61,7 +61,12 @@ CREATE TABLE services (
     published_port INTEGER NOT NULL DEFAULT 0,
     volumes JSONB NOT NULL DEFAULT '[]'::jsonb,
     maintenance_mode BOOLEAN NOT NULL DEFAULT false,
-    basic_auth_users TEXT NOT NULL DEFAULT ''
+    basic_auth_users TEXT NOT NULL DEFAULT '',
+    builder VARCHAR(32) NOT NULL DEFAULT 'auto',
+    cpu_reserve VARCHAR(20) NOT NULL DEFAULT '',
+    memory_reserve VARCHAR(20) NOT NULL DEFAULT '',
+    static_build_cmd VARCHAR(255) NOT NULL DEFAULT '',
+    static_dir VARCHAR(255) NOT NULL DEFAULT ''
 );
 
 CREATE TABLE service_domains (