diff --git a/.doc/doki/doc/ruki/semantics.md b/.doc/doki/doc/ruki/semantics.md
index 4f25679..796f6c8 100644
--- a/.doc/doki/doc/ruki/semantics.md
+++ b/.doc/doki/doc/ruki/semantics.md
@@ -34,8 +34,10 @@ This page explains how Ruki statements, triggers, conditions, and expressions be
 
 - `create` is a list of assignments.
 - At least one assignment is required.
+- The resulting task must have a non-empty `title`. This can come from an explicit `title=...` assignment or from the task template.
 - Duplicate assignments to the same field are rejected.
 - Every assigned field must exist in the injected schema.
+- `id`, `createdBy`, `createdAt`, and `updatedAt` are immutable and cannot be assigned.
 
 `update`
 
@@ -43,6 +45,7 @@ This page explains how Ruki statements, triggers, conditions, and expressions be
 - At least one assignment in `set` is required.
 - The `where` clause and every right-hand side expression are validated.
 - Duplicate assignments inside `set` are rejected.
+- `id`, `createdBy`, `createdAt`, and `updatedAt` are immutable and cannot be assigned.
 
 `delete`
 
diff --git a/.doc/doki/doc/ruki/types-and-values.md b/.doc/doki/doc/ruki/types-and-values.md
index ad914d0..b3ad284 100644
--- a/.doc/doki/doc/ruki/types-and-values.md
+++ b/.doc/doki/doc/ruki/types-and-values.md
@@ -81,7 +81,8 @@ Qualified and unqualified references are not literals, but they participate in t
 
 Implemented behavior:
 
-- `empty` can be assigned to any field type
+- `empty` can be assigned to most field types
+- `title`, `status`, `type`, and `priority` reject `empty` assignment — these fields are required
 - `empty` can be compared against any typed expression
 - `is empty` and `is not empty` are allowed for any expression type
 
diff --git a/.doc/doki/doc/ruki/validation-and-errors.md b/.doc/doki/doc/ruki/validation-and-errors.md
index 4ed8114..b1f1fb7 100644
--- a/.doc/doki/doc/ruki/validation-and-errors.md
+++ b/.doc/doki/doc/ruki/validation-and-errors.md
@@ -80,6 +80,15 @@ select where foo = "bar"
 create title="x" foo="bar"
 ```
 
+Immutable field errors:
+
+- `id`, `createdBy`, `createdAt`, and `updatedAt` cannot be assigned in `create` or `update`
+
+```sql
+create title="x" id="TIKI-ABC123"
+update where status = "done" set createdBy="someone"
+```
+
 Qualifier misuse:
 
 - `old.` and `new.` are invalid in standalone statements
@@ -97,6 +106,18 @@ before delete where new.status = "done" deny "x"
 before update where dependsOn any old.status = "done" deny "blocked"
 ```
 
+## Required field errors
+
+The resulting task from `create` must have a non-empty `title`. If the template does not provide one, a `title=...` assignment is required.
+
+`title`, `status`, `type`, and `priority` reject `empty` assignment:
+
+```sql
+create title="" priority=2
+create title="x" status=empty
+update where id = "TIKI-ABC123" set priority=empty
+```
+
 ## Type and operator errors
 
 Comparison mismatches:
diff --git a/internal/ruki/runtime/runner.go b/internal/ruki/runtime/runner.go
index cbcff53..beb60d7 100644
--- a/internal/ruki/runtime/runner.go
+++ b/internal/ruki/runtime/runner.go
@@ -7,11 +7,11 @@ import (
 
 	"github.com/boolean-maybe/tiki/ruki"
 	"github.com/boolean-maybe/tiki/store"
+	"github.com/boolean-maybe/tiki/task"
 )
 
 // RunQuery parses and executes a ruki statement against the given store,
-// writing formatted results to out. SELECT and UPDATE are supported;
-// CREATE and DELETE are rejected.
+// writing formatted results to out.
 func RunQuery(taskStore store.Store, query string, out io.Writer) error {
 	query = strings.TrimSuffix(strings.TrimSpace(query), ";")
 	if query == "" {
@@ -32,6 +32,20 @@ func RunQuery(taskStore store.Store, query string, out io.Writer) error {
 		return fmt.Errorf("parse: %w", err)
 	}
 
+	// for CREATE, fetch template before execution so field references
+	// (e.g. tags=tags+["new"]) resolve from template defaults
+	var template *task.Task
+	if stmt.Create != nil {
+		template, err = taskStore.NewTaskTemplate()
+		if err != nil {
+			return fmt.Errorf("create template: %w", err)
+		}
+		if template == nil {
+			return fmt.Errorf("create template: store returned nil template")
+		}
+		executor.SetTemplate(template)
+	}
+
 	tasks := taskStore.GetAllTasks()
 	result, err := executor.Execute(stmt, tasks)
 	if err != nil {
@@ -46,13 +60,37 @@ func RunQuery(taskStore store.Store, query string, out io.Writer) error {
 	case result.Update != nil:
 		return persistAndSummarize(taskStore, result.Update, out)
 
+	case result.Create != nil:
+		return persistCreate(taskStore, result.Create, template, out)
+
+	case result.Delete != nil:
+		return persistDelete(taskStore, result.Delete, out)
+
 	default:
 		return fmt.Errorf("unsupported statement type")
 	}
 }
 
-// RunSelectQuery is the legacy entry point. It delegates to RunQuery.
+// RunSelectQuery is the legacy entry point restricted to SELECT statements.
+// Non-SELECT statements (CREATE, UPDATE, DELETE) are rejected to preserve
+// read-only semantics expected by callers of this function.
 func RunSelectQuery(taskStore store.Store, query string, out io.Writer) error {
+	trimmed := strings.TrimSuffix(strings.TrimSpace(query), ";")
+	if trimmed == "" {
+		return fmt.Errorf("empty query")
+	}
+
+	schema := NewSchema()
+	parser := ruki.NewParser(schema)
+	stmt, err := parser.ParseStatement(trimmed)
+	if err != nil {
+		return fmt.Errorf("parse: %w", err)
+	}
+
+	if stmt.Select == nil {
+		return fmt.Errorf("RunSelectQuery only supports SELECT statements")
+	}
+
 	return RunQuery(taskStore, query, out)
 }
 
@@ -80,6 +118,44 @@ func persistAndSummarize(taskStore store.Store, ur *ruki.UpdateResult, out io.Wr
 	return nil
 }
 
+func persistCreate(taskStore store.Store, cr *ruki.CreateResult, template *task.Task, out io.Writer) error {
+	t := cr.Task
+	t.ID = template.ID
+	t.CreatedBy = template.CreatedBy
+	t.CreatedAt = template.CreatedAt
+
+	if strings.TrimSpace(t.Title) == "" {
+		return fmt.Errorf("create requires a title")
+	}
+
+	if err := taskStore.CreateTask(t); err != nil {
+		return fmt.Errorf("create task: %w", err)
+	}
+
+	_, _ = fmt.Fprintf(out, "created %s\n", t.ID)
+	return nil
+}
+
+func persistDelete(taskStore store.Store, dr *ruki.DeleteResult, out io.Writer) error {
+	var succeeded, failed int
+	for _, t := range dr.Deleted {
+		taskStore.DeleteTask(t.ID)
+		if taskStore.GetTask(t.ID) != nil {
+			failed++
+		} else {
+			succeeded++
+		}
+	}
+
+	if failed > 0 {
+		_, _ = fmt.Fprintf(out, "deleted %d tasks (%d failed)\n", succeeded, failed)
+		return fmt.Errorf("delete partially failed: %d of %d tasks failed", failed, succeeded+failed)
+	}
+
+	_, _ = fmt.Fprintf(out, "deleted %d tasks\n", succeeded)
+	return nil
+}
+
 // resolveUser returns the current user name from the store.
 // Returns an error if the user cannot be determined.
 func resolveUser(s store.Store) (string, error) {
diff --git a/internal/ruki/runtime/runner_test.go b/internal/ruki/runtime/runner_test.go
index 292a143..1adee2d 100644
--- a/internal/ruki/runtime/runner_test.go
+++ b/internal/ruki/runtime/runner_test.go
@@ -88,16 +88,29 @@ func TestRunSelectQueryParseError(t *testing.T) {
 	}
 }
 
-func TestRunSelectQueryNonSelectRejected(t *testing.T) {
+func TestRunSelectQueryRejectsNonSelect(t *testing.T) {
 	s := setupRunnerTest(t)
 
-	var buf bytes.Buffer
-	err := RunSelectQuery(s, `create title="test"`, &buf)
-	if err == nil {
-		t.Fatal("expected error for unsupported statement")
+	tests := []struct {
+		name  string
+		query string
+	}{
+		{"rejects create", `create title="via legacy"`},
+		{"rejects update", `update where id = "TIKI-AAA001" set title="x"`},
+		{"rejects delete", `delete where id = "TIKI-AAA001"`},
 	}
-	if !strings.Contains(err.Error(), "not supported") {
-		t.Errorf("error should mention not supported: %v", err)
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var buf bytes.Buffer
+			err := RunSelectQuery(s, tt.query, &buf)
+			if err == nil {
+				t.Fatal("expected error for non-SELECT statement via RunSelectQuery")
+			}
+			if !strings.Contains(err.Error(), "only supports SELECT") {
+				t.Errorf("expected 'only supports SELECT' error, got: %v", err)
+			}
+		})
 	}
 }
 
@@ -314,11 +327,11 @@ func TestRunQueryResolveUserErrorUpdate(t *testing.T) {
 func TestRunQueryExecuteError(t *testing.T) {
 	s := setupRunnerTest(t)
 
-	// delete statement is parsed but executor returns "not supported" error
+	// call() is rejected at runtime, triggering an execute error
 	var buf bytes.Buffer
-	err := RunQuery(s, `delete where id = "X"`, &buf)
+	err := RunQuery(s, `select where call("echo") = "x"`, &buf)
 	if err == nil {
-		t.Fatal("expected error for unsupported delete")
+		t.Fatal("expected execute error")
 	}
 	if !strings.Contains(err.Error(), "execute") {
 		t.Errorf("expected execute error, got: %v", err)
@@ -337,3 +350,221 @@ func TestRunQueryUpdateInvalidPointsE2E(t *testing.T) {
 		t.Errorf("expected 'invalid points' error, got: %v", err)
 	}
 }
+
+// --- CREATE via runner ---
+
+func TestRunQueryCreatePersists(t *testing.T) {
+	s := setupRunnerTest(t)
+
+	var buf bytes.Buffer
+	err := RunQuery(s, `create title="New Task" status="ready" priority=1`, &buf)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	out := buf.String()
+	if !strings.Contains(out, "created TIKI-") {
+		t.Fatalf("expected 'created TIKI-' in output, got: %s", out)
+	}
+
+	// verify task exists in store
+	allTasks := s.GetAllTasks()
+	var found *task.Task
+	for _, tk := range allTasks {
+		if tk.Title == "New Task" {
+			found = tk
+			break
+		}
+	}
+	if found == nil {
+		t.Fatal("created task not found in store")
+	}
+	if !strings.HasPrefix(found.ID, "TIKI-") || len(found.ID) != 11 {
+		t.Errorf("ID = %q, want TIKI-XXXXXX format (11 chars)", found.ID)
+	}
+	if found.Priority != 1 {
+		t.Errorf("priority = %d, want 1", found.Priority)
+	}
+}
+
+func TestRunQueryCreateMissingTitle(t *testing.T) {
+	s := setupRunnerTest(t)
+
+	var buf bytes.Buffer
+	err := RunQuery(s, `create priority=1 status="ready"`, &buf)
+	if err == nil {
+		t.Fatal("expected error for missing title")
+	}
+	if !strings.Contains(err.Error(), "title") {
+		t.Errorf("expected title error, got: %v", err)
+	}
+}
+
+func TestRunQueryCreateTemplateDefaults(t *testing.T) {
+	s := setupRunnerTest(t)
+
+	var buf bytes.Buffer
+	err := RunQuery(s, `create title="Templated" tags=tags+["extra"]`, &buf)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	allTasks := s.GetAllTasks()
+	var found *task.Task
+	for _, tk := range allTasks {
+		if tk.Title == "Templated" {
+			found = tk
+			break
+		}
+	}
+	if found == nil {
+		t.Fatal("created task not found in store")
+	}
+	// InMemoryStore template has tags=["idea"], so result should be ["idea", "extra"]
+	if len(found.Tags) != 2 || found.Tags[0] != "idea" || found.Tags[1] != "extra" {
+		t.Errorf("tags = %v, want [idea extra]", found.Tags)
+	}
+	// priority should be template default (7)
+	if found.Priority != 7 {
+		t.Errorf("priority = %d, want 7 (template default)", found.Priority)
+	}
+}
+
+func TestRunQueryCreateTemplateFailure(t *testing.T) {
+	s := setupRunnerTest(t)
+	fs := &failingTemplateStore{Store: s}
+
+	var buf bytes.Buffer
+	err := RunQuery(fs, `create title="test"`, &buf)
+	if err == nil {
+		t.Fatal("expected error for template failure")
+	}
+	if !strings.Contains(err.Error(), "create template") {
+		t.Errorf("expected 'create template' error, got: %v", err)
+	}
+}
+
+// failingTemplateStore wraps a Store and fails NewTaskTemplate.
+type failingTemplateStore struct {
+	store.Store
+}
+
+func (f *failingTemplateStore) NewTaskTemplate() (*task.Task, error) {
+	return nil, fmt.Errorf("simulated template failure")
+}
+
+func TestRunQueryCreateNilTemplate(t *testing.T) {
+	s := setupRunnerTest(t)
+	fs := &nilTemplateStore{Store: s}
+
+	var buf bytes.Buffer
+	err := RunQuery(fs, `create title="test"`, &buf)
+	if err == nil {
+		t.Fatal("expected error for nil template")
+	}
+	if !strings.Contains(err.Error(), "nil template") {
+		t.Errorf("expected 'nil template' error, got: %v", err)
+	}
+}
+
+// nilTemplateStore wraps a Store and returns (nil, nil) from NewTaskTemplate.
+type nilTemplateStore struct {
+	store.Store
+}
+
+func (f *nilTemplateStore) NewTaskTemplate() (*task.Task, error) {
+	return nil, nil
+}
+
+func TestRunQueryCreateTaskFailure(t *testing.T) {
+	s := setupRunnerTest(t)
+	fs := &failingCreateStore{Store: s}
+
+	var buf bytes.Buffer
+	err := RunQuery(fs, `create title="test"`, &buf)
+	if err == nil {
+		t.Fatal("expected error for CreateTask failure")
+	}
+	if !strings.Contains(err.Error(), "create task") {
+		t.Errorf("expected 'create task' error, got: %v", err)
+	}
+}
+
+// failingCreateStore wraps a Store and fails CreateTask.
+type failingCreateStore struct {
+	store.Store
+}
+
+func (f *failingCreateStore) CreateTask(t *task.Task) error {
+	return fmt.Errorf("simulated create failure")
+}
+
+// --- DELETE via runner ---
+
+func TestRunQueryDeletePersists(t *testing.T) {
+	s := setupRunnerTest(t)
+
+	var buf bytes.Buffer
+	err := RunQuery(s, `delete where id = "TIKI-AAA001"`, &buf)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	out := buf.String()
+	if !strings.Contains(out, "deleted 1 tasks") {
+		t.Errorf("expected 'deleted 1 tasks' in output, got: %s", out)
+	}
+	if s.GetTask("TIKI-AAA001") != nil {
+		t.Error("task should be deleted from store")
+	}
+}
+
+func TestRunQueryDeleteZeroMatches(t *testing.T) {
+	s := setupRunnerTest(t)
+
+	var buf bytes.Buffer
+	err := RunQuery(s, `delete where id = "NONEXISTENT"`, &buf)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	out := buf.String()
+	if !strings.Contains(out, "deleted 0 tasks") {
+		t.Errorf("expected 'deleted 0 tasks' in output, got: %s", out)
+	}
+}
+
+func TestRunQueryDeletePartialFailure(t *testing.T) {
+	s := setupRunnerTest(t)
+	// add a second ready task so we match multiple
+	_ = s.CreateTask(&task.Task{ID: "TIKI-CCC003", Title: "Third", Status: "ready", Priority: 3})
+
+	fs := &failingDeleteStore{Store: s, failID: "TIKI-AAA001"}
+
+	var buf bytes.Buffer
+	err := RunQuery(fs, `delete where status = "ready"`, &buf)
+
+	out := buf.String()
+	if err == nil {
+		t.Fatal("expected error for partial failure")
+	}
+	if !strings.Contains(out, "failed") {
+		t.Errorf("expected 'failed' in output, got: %s", out)
+	}
+	if !strings.Contains(err.Error(), "partially failed") {
+		t.Errorf("expected 'partially failed' in error, got: %v", err)
+	}
+}
+
+// failingDeleteStore wraps a Store and silently no-ops DeleteTask for a specific ID.
+type failingDeleteStore struct {
+	store.Store
+	failID string
+}
+
+func (f *failingDeleteStore) DeleteTask(id string) {
+	if id == f.failID {
+		return // simulate silent failure
+	}
+	f.Store.DeleteTask(id)
+}
diff --git a/plugin/filter/duration.go b/plugin/filter/duration.go
index a4bd87f..c9be9d3 100644
--- a/plugin/filter/duration.go
+++ b/plugin/filter/duration.go
@@ -3,41 +3,25 @@ package filter
 import (
 	"fmt"
 	"regexp"
-	"strconv"
 	"strings"
 	"time"
+
+	"github.com/boolean-maybe/tiki/util/duration"
 )
 
-// Duration pattern: number followed by unit (month, week, day, hour, min)
-var durationPattern = regexp.MustCompile(`^(\d+)(month|week|day|hour|min)s?$`)
+// durationPattern matches a number followed by a duration unit, with optional plural "s".
+var durationPattern = regexp.MustCompile(`^(\d+)(` + duration.Pattern() + `)s?$`)
 
-// IsDurationLiteral checks if a string is a valid duration literal
+// IsDurationLiteral checks if a string is a valid duration literal.
 func IsDurationLiteral(s string) bool {
 	return durationPattern.MatchString(strings.ToLower(s))
 }
 
-// ParseDuration parses a duration literal like "24hour" or "1week"
+// ParseDuration parses a duration literal like "24hour" or "1week".
 func ParseDuration(s string) (time.Duration, error) {
-	s = strings.ToLower(s)
-	matches := durationPattern.FindStringSubmatch(s)
-	if matches == nil {
+	val, unit, err := duration.Parse(strings.ToLower(s))
+	if err != nil {
 		return 0, fmt.Errorf("invalid duration: %s", s)
 	}
-
-	value, _ := strconv.Atoi(matches[1])
-	unit := matches[2]
-
-	switch unit {
-	case "min":
-		return time.Duration(value) * time.Minute, nil
-	case "hour":
-		return time.Duration(value) * time.Hour, nil
-	case "day":
-		return time.Duration(value) * 24 * time.Hour, nil
-	case "week":
-		return time.Duration(value) * 7 * 24 * time.Hour, nil
-	case "month":
-		return time.Duration(value) * 30 * 24 * time.Hour, nil
-	}
-	return 0, fmt.Errorf("unknown duration unit: %s", unit)
+	return duration.ToDuration(val, unit)
 }
diff --git a/plugin/filter/filter_time_test.go b/plugin/filter/filter_time_test.go
index 62f38f8..a6fd01b 100644
--- a/plugin/filter/filter_time_test.go
+++ b/plugin/filter/filter_time_test.go
@@ -203,6 +203,34 @@ func TestTimeExpressions(t *testing.T) {
 			expect: true, // Updated 5 seconds ago
 		},
 
+		// seconds unit
+		{
+			name:   "seconds - under threshold",
+			expr:   "NOW - UpdatedAt < 30secs",
+			task:   &task.Task{UpdatedAt: now.Add(-10 * time.Second)},
+			expect: true, // Updated 10 seconds ago
+		},
+		{
+			name:   "seconds - over threshold",
+			expr:   "NOW - UpdatedAt < 10sec",
+			task:   &task.Task{UpdatedAt: now.Add(-30 * time.Second)},
+			expect: false, // Updated 30 seconds ago
+		},
+
+		// years unit
+		{
+			name:   "years - under threshold",
+			expr:   "NOW - CreatedAt < 1year",
+			task:   &task.Task{CreatedAt: now.Add(-200 * 24 * time.Hour)},
+			expect: true, // Created 200 days ago, less than 365 days
+		},
+		{
+			name:   "years - over threshold",
+			expr:   "NOW - CreatedAt > 1year",
+			task:   &task.Task{CreatedAt: now.Add(-400 * 24 * time.Hour)},
+			expect: true, // Created 400 days ago, more than 365 days
+		},
+
 		// Edge case: future time (shouldn't normally happen, but test negative duration)
 		{
 			name:   "future time - negative duration",
@@ -260,6 +288,16 @@ func TestTimeExpressionParsing(t *testing.T) {
 			expr:        "NOW - UpdatedAt < 2months",
 			shouldError: false,
 		},
+		{
+			name:        "valid with seconds",
+			expr:        "NOW - UpdatedAt < 30secs",
+			shouldError: false,
+		},
+		{
+			name:        "valid with years",
+			expr:        "NOW - CreatedAt > 1year",
+			shouldError: false,
+		},
 		{
 			name:        "valid with parentheses",
 			expr:        "(NOW - UpdatedAt < 1hour)",
diff --git a/ruki/executor.go b/ruki/executor.go
index c7449cc..52dcc9f 100644
--- a/ruki/executor.go
+++ b/ruki/executor.go
@@ -7,14 +7,21 @@ import (
 	"time"
 
 	"github.com/boolean-maybe/tiki/task"
+	"github.com/boolean-maybe/tiki/util/duration"
 )
 
 // Executor evaluates parsed ruki statements against a set of tasks.
 type Executor struct {
 	schema   Schema
 	userFunc func() string
+	template *task.Task
 }
 
+// SetTemplate sets the base task template for CREATE execution.
+// When set, CREATE assignments are evaluated against a clone of this template,
+// so field references (e.g. tags=tags+["new"]) resolve from template defaults.
+func (e *Executor) SetTemplate(t *task.Task) { e.template = t }
+
 // NewExecutor constructs an Executor with the given schema and user function.
 // If userFunc is nil, calling user() at runtime will return "".
 func NewExecutor(schema Schema, userFunc func() string) *Executor {
@@ -29,6 +36,8 @@ func NewExecutor(schema Schema, userFunc func() string) *Executor {
 type Result struct {
 	Select *TaskProjection
 	Update *UpdateResult
+	Create *CreateResult
+	Delete *DeleteResult
 }
 
 // UpdateResult holds the cloned, mutated tasks produced by an UPDATE statement.
@@ -36,6 +45,16 @@ type UpdateResult struct {
 	Updated []*task.Task
 }
 
+// CreateResult holds the new task produced by a CREATE statement.
+type CreateResult struct {
+	Task *task.Task
+}
+
+// DeleteResult holds the tasks matched by a DELETE statement's WHERE clause.
+type DeleteResult struct {
+	Deleted []*task.Task
+}
+
 // TaskProjection holds the filtered, sorted tasks and the requested field list.
 type TaskProjection struct {
 	Tasks  []*task.Task
@@ -51,11 +70,11 @@ func (e *Executor) Execute(stmt *Statement, tasks []*task.Task) (*Result, error)
 	case stmt.Select != nil:
 		return e.executeSelect(stmt.Select, tasks)
 	case stmt.Create != nil:
-		return nil, fmt.Errorf("create is not supported yet")
+		return e.executeCreate(stmt.Create, tasks)
 	case stmt.Update != nil:
 		return e.executeUpdate(stmt.Update, tasks)
 	case stmt.Delete != nil:
-		return nil, fmt.Errorf("delete is not supported yet")
+		return e.executeDelete(stmt.Delete, tasks)
 	default:
 		return nil, fmt.Errorf("empty statement")
 	}
@@ -105,6 +124,36 @@ func (e *Executor) executeUpdate(upd *UpdateStmt, tasks []*task.Task) (*Result,
 	return &Result{Update: &UpdateResult{Updated: clones}}, nil
 }
 
+func (e *Executor) executeCreate(cr *CreateStmt, tasks []*task.Task) (*Result, error) {
+	var t *task.Task
+	if e.template != nil {
+		t = e.template.Clone()
+	} else {
+		t = &task.Task{}
+	}
+
+	for _, a := range cr.Assignments {
+		val, err := e.evalExpr(a.Value, t, tasks)
+		if err != nil {
+			return nil, fmt.Errorf("field %q: %w", a.Field, err)
+		}
+		if err := e.setField(t, a.Field, val); err != nil {
+			return nil, fmt.Errorf("field %q: %w", a.Field, err)
+		}
+	}
+
+	return &Result{Create: &CreateResult{Task: t}}, nil
+}
+
+func (e *Executor) executeDelete(del *DeleteStmt, tasks []*task.Task) (*Result, error) {
+	matched, err := e.filterTasks(del.Where, tasks)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Result{Delete: &DeleteResult{Deleted: matched}}, nil
+}
+
 func (e *Executor) setField(t *task.Task, name string, val interface{}) error {
 	switch name {
 	case "id", "createdBy", "createdAt", "updatedAt":
@@ -452,7 +501,11 @@ func (e *Executor) evalExpr(expr Expr, t *task.Task, allTasks []*task.Task) (int
 	case *DateLiteral:
 		return expr.Value, nil
 	case *DurationLiteral:
-		return durationToTimeDelta(expr.Value, expr.Unit), nil
+		d, err := duration.ToDuration(expr.Value, expr.Unit)
+		if err != nil {
+			return nil, err
+		}
+		return d, nil
 	case *ListLiteral:
 		return e.evalListLiteral(expr, t, allTasks)
 	case *EmptyLiteral:
@@ -1085,22 +1138,3 @@ func isZeroValue(v interface{}) bool {
 		return false
 	}
 }
-
-func durationToTimeDelta(value int, unit string) time.Duration {
-	switch unit {
-	case "day":
-		return time.Duration(value) * 24 * time.Hour
-	case "week":
-		return time.Duration(value) * 7 * 24 * time.Hour
-	case "month":
-		return time.Duration(value) * 30 * 24 * time.Hour
-	case "year":
-		return time.Duration(value) * 365 * 24 * time.Hour
-	case "hour":
-		return time.Duration(value) * time.Hour
-	case "minute":
-		return time.Duration(value) * time.Minute
-	default:
-		return time.Duration(value) * 24 * time.Hour
-	}
-}
diff --git a/ruki/executor_test.go b/ruki/executor_test.go
index b465ee4..58bc088 100644
--- a/ruki/executor_test.go
+++ b/ruki/executor_test.go
@@ -698,37 +698,343 @@ func TestExecuteCallRejected(t *testing.T) {
 	}
 }
 
-// --- unsupported statement types ---
+// --- CREATE execution ---
 
-func TestExecuteUnsupportedStatements(t *testing.T) {
+func TestExecuteCreateBasic(t *testing.T) {
 	e := newTestExecutor()
 	p := newTestParser()
 
-	tests := []struct {
-		name  string
-		input string
-	}{
-		{"create", `create title="test"`},
-		{"delete", `delete where id = "X"`},
+	stmt, err := p.ParseStatement(`create title="Fix login" priority=2 status="ready"`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
 	}
+	result, err := e.Execute(stmt, nil)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	if result.Create == nil {
+		t.Fatal("expected Create result")
+	}
+	tk := result.Create.Task
+	if tk.Title != "Fix login" {
+		t.Errorf("title = %q, want %q", tk.Title, "Fix login")
+	}
+	if tk.Priority != 2 {
+		t.Errorf("priority = %d, want 2", tk.Priority)
+	}
+	if tk.Status != "ready" {
+		t.Errorf("status = %q, want %q", tk.Status, "ready")
+	}
+}
 
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			stmt, err := p.ParseStatement(tt.input)
-			if err != nil {
-				t.Fatalf("parse: %v", err)
+func TestExecuteCreateWithUser(t *testing.T) {
+	e := newTestExecutor() // userFunc returns "alice"
+	p := newTestParser()
+
+	stmt, err := p.ParseStatement(`create title="test" assignee=user()`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, nil)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	if result.Create.Task.Assignee != "alice" {
+		t.Errorf("assignee = %q, want %q", result.Create.Task.Assignee, "alice")
+	}
+}
+
+func TestExecuteCreateEnumNormalization(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+
+	stmt, err := p.ParseStatement(`create title="test" status="todo" type="feature"`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, nil)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	tk := result.Create.Task
+	if tk.Status != "ready" {
+		t.Errorf("status = %q, want normalized %q", tk.Status, "ready")
+	}
+	if tk.Type != "story" {
+		t.Errorf("type = %q, want normalized %q", tk.Type, "story")
+	}
+}
+
+func TestExecuteCreateImmutableFieldRejected(t *testing.T) {
+	e := newTestExecutor()
+
+	for _, field := range []string{"id", "createdBy", "createdAt", "updatedAt"} {
+		t.Run(field, func(t *testing.T) {
+			stmt := &Statement{
+				Create: &CreateStmt{
+					Assignments: []Assignment{
+						{Field: "title", Value: &StringLiteral{Value: "x"}},
+						{Field: field, Value: &StringLiteral{Value: "test"}},
+					},
+				},
 			}
-			_, err = e.Execute(stmt, makeTasks())
+			_, err := e.Execute(stmt, nil)
 			if err == nil {
-				t.Fatal("expected error for unsupported statement")
+				t.Fatal("expected error for immutable field")
 			}
-			if !strings.Contains(err.Error(), "not supported") {
-				t.Fatalf("expected 'not supported' error, got: %v", err)
+			if !strings.Contains(err.Error(), "immutable") {
+				t.Errorf("expected immutable error, got: %v", err)
 			}
 		})
 	}
 }
 
+func TestExecuteCreateEmptyTitleRejected(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+
+	stmt, err := p.ParseStatement(`create title=""`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	_, err = e.Execute(stmt, nil)
+	if err == nil {
+		t.Fatal("expected error for empty title")
+	}
+	if !strings.Contains(err.Error(), "empty") {
+		t.Errorf("expected empty error, got: %v", err)
+	}
+}
+
+func TestExecuteCreateExprError(t *testing.T) {
+	e := newTestExecutor()
+
+	stmt := &Statement{
+		Create: &CreateStmt{
+			Assignments: []Assignment{
+				{Field: "title", Value: &QualifiedRef{Qualifier: "old", Name: "title"}},
+			},
+		},
+	}
+	_, err := e.Execute(stmt, nil)
+	if err == nil {
+		t.Fatal("expected error from eval expression")
+	}
+}
+
+func TestExecuteCreateListField(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+
+	stmt, err := p.ParseStatement(`create title="test" tags=["a","b"]`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, nil)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	tags := result.Create.Task.Tags
+	if len(tags) != 2 || tags[0] != "a" || tags[1] != "b" {
+		t.Errorf("tags = %v, want [a b]", tags)
+	}
+}
+
+func TestExecuteCreateDateField(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+
+	stmt, err := p.ParseStatement(`create title="test" due=2026-06-01`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, nil)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	due := result.Create.Task.Due
+	if due.Year() != 2026 || due.Month() != 6 || due.Day() != 1 {
+		t.Errorf("due = %v, want 2026-06-01", due)
+	}
+}
+
+func TestExecuteCreatePriorityOutOfRange(t *testing.T) {
+	e := newTestExecutor()
+
+	for _, prio := range []int{0, 99, -1} {
+		t.Run(fmt.Sprintf("priority=%d", prio), func(t *testing.T) {
+			stmt := &Statement{
+				Create: &CreateStmt{
+					Assignments: []Assignment{
+						{Field: "title", Value: &StringLiteral{Value: "x"}},
+						{Field: "priority", Value: &IntLiteral{Value: prio}},
+					},
+				},
+			}
+			_, err := e.Execute(stmt, nil)
+			if err == nil {
+				t.Fatal("expected error for out-of-range priority")
+			}
+		})
+	}
+}
+
+func TestExecuteCreateEmptyTasks(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+
+	stmt, err := p.ParseStatement(`create title="test"`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, []*task.Task{})
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	if result.Create.Task.Title != "test" {
+		t.Errorf("title = %q, want %q", result.Create.Task.Title, "test")
+	}
+}
+
+func TestExecuteCreateWithTemplate(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+
+	// set template with tags=["idea"] and priority=7
+	e.SetTemplate(&task.Task{
+		Tags:     []string{"idea"},
+		Priority: 7,
+		Status:   "ready",
+		Type:     "story",
+	})
+
+	stmt, err := p.ParseStatement(`create title="x" tags=tags+["new"]`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, nil)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	tk := result.Create.Task
+	// tags should be template's ["idea"] + ["new"]
+	if len(tk.Tags) != 2 || tk.Tags[0] != "idea" || tk.Tags[1] != "new" {
+		t.Errorf("tags = %v, want [idea new]", tk.Tags)
+	}
+	// priority should be preserved from template (not set by assignment)
+	if tk.Priority != 7 {
+		t.Errorf("priority = %d, want 7 (template default)", tk.Priority)
+	}
+}
+
+func TestExecuteCreateWithoutTemplate(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+	// no SetTemplate call — template is nil
+
+	stmt, err := p.ParseStatement(`create title="x" priority=3`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, nil)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	tk := result.Create.Task
+	if tk.Title != "x" {
+		t.Errorf("title = %q, want %q", tk.Title, "x")
+	}
+	if tk.Priority != 3 {
+		t.Errorf("priority = %d, want 3", tk.Priority)
+	}
+	// unset fields should be zero-valued
+	if tk.Points != 0 {
+		t.Errorf("points = %d, want 0 (zero-value)", tk.Points)
+	}
+}
+
+// --- DELETE execution ---
+
+func TestExecuteDeleteBasic(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+	tasks := makeTasks()
+
+	stmt, err := p.ParseStatement(`delete where id = "TIKI-000001"`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, tasks)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	if result.Delete == nil {
+		t.Fatal("expected Delete result")
+	}
+	if len(result.Delete.Deleted) != 1 {
+		t.Fatalf("expected 1 deleted, got %d", len(result.Delete.Deleted))
+	}
+	if result.Delete.Deleted[0].ID != "TIKI-000001" {
+		t.Errorf("deleted ID = %q, want TIKI-000001", result.Delete.Deleted[0].ID)
+	}
+}
+
+func TestExecuteDeleteMultipleMatches(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+	tasks := makeTasks()
+
+	stmt, err := p.ParseStatement(`delete where type = "story"`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, tasks)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	// TIKI-000001 and TIKI-000003 are stories
+	if len(result.Delete.Deleted) != 2 {
+		t.Fatalf("expected 2 deleted, got %d", len(result.Delete.Deleted))
+	}
+}
+
+func TestExecuteDeleteNoMatches(t *testing.T) {
+	e := newTestExecutor()
+	p := newTestParser()
+	tasks := makeTasks()
+
+	stmt, err := p.ParseStatement(`delete where id = "NONEXISTENT"`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	result, err := e.Execute(stmt, tasks)
+	if err != nil {
+		t.Fatalf("execute: %v", err)
+	}
+	if len(result.Delete.Deleted) != 0 {
+		t.Fatalf("expected 0 deleted, got %d", len(result.Delete.Deleted))
+	}
+}
+
+func TestExecuteDeleteWhereError(t *testing.T) {
+	e := newTestExecutor()
+	tasks := makeTasks()
+
+	stmt := &Statement{
+		Delete: &DeleteStmt{
+			Where: &CompareExpr{
+				Left:  &QualifiedRef{Qualifier: "old", Name: "status"},
+				Op:    "=",
+				Right: &StringLiteral{Value: "done"},
+			},
+		},
+	}
+	_, err := e.Execute(stmt, tasks)
+	if err == nil {
+		t.Fatal("expected error from WHERE evaluation")
+	}
+}
+
 // --- quantifier ---
 
 func TestExecuteQuantifier(t *testing.T) {
@@ -1178,26 +1484,28 @@ func TestIsZeroValue(t *testing.T) {
 
 // --- durationToTimeDelta full coverage ---
 
-func TestDurationToTimeDelta(t *testing.T) {
-	tests := []struct {
-		unit string
-		want time.Duration
-	}{
-		{"day", 24 * time.Hour},
-		{"week", 7 * 24 * time.Hour},
-		{"month", 30 * 24 * time.Hour},
-		{"year", 365 * 24 * time.Hour},
-		{"hour", time.Hour},
-		{"minute", time.Minute},
-		{"unknown", 24 * time.Hour}, // default = day
+func TestDurationLiteralUnknownUnitError(t *testing.T) {
+	e := &Executor{}
+	tasks := []*task.Task{{ID: "TIKI-AAA001", Title: "test"}}
+	// unknown unit should produce an error, not silently default to days
+	stmt, err := newTestParser().ParseStatement(`select where due > 2026-01-01 + 1day`)
+	if err != nil {
+		t.Fatal(err)
 	}
-	for _, tt := range tests {
-		t.Run(tt.unit, func(t *testing.T) {
-			got := durationToTimeDelta(1, tt.unit)
-			if got != tt.want {
-				t.Errorf("durationToTimeDelta(1, %q) = %v, want %v", tt.unit, got, tt.want)
-			}
-		})
+	// manually inject an unknown unit into the AST
+	cmp, ok := stmt.Select.Where.(*CompareExpr)
+	if !ok {
+		t.Fatal("expected *CompareExpr")
+	}
+	add, ok := cmp.Right.(*BinaryExpr)
+	if !ok {
+		t.Fatal("expected *BinaryExpr")
+	}
+	add.Right = &DurationLiteral{Value: 1, Unit: "bogus"}
+
+	_, err = e.Execute(stmt, tasks)
+	if err == nil {
+		t.Fatal("expected error for unknown duration unit, got nil")
 	}
 }
 
diff --git a/ruki/lexer.go b/ruki/lexer.go
index 0a317df..8d2698a 100644
--- a/ruki/lexer.go
+++ b/ruki/lexer.go
@@ -1,13 +1,17 @@
 package ruki
 
-import "github.com/alecthomas/participle/v2/lexer"
+import (
+	"github.com/alecthomas/participle/v2/lexer"
+
+	"github.com/boolean-maybe/tiki/util/duration"
+)
 
 // rukiLexer defines the token rules for the ruki DSL.
 // rule ordering is critical: longer/more-specific patterns first.
 var rukiLexer = lexer.MustSimple([]lexer.SimpleRule{
 	{Name: "Comment", Pattern: `--[^\n]*`},
 	{Name: "Whitespace", Pattern: `\s+`},
-	{Name: "Duration", Pattern: `\d+(?:sec|min|hour|day|week|month|year)s?`},
+	{Name: "Duration", Pattern: `\d+(?:` + duration.Pattern() + `)s?`},
 	{Name: "Date", Pattern: `\d{4}-\d{2}-\d{2}`},
 	{Name: "Int", Pattern: `\d+`},
 	{Name: "String", Pattern: `"(?:[^"\\]|\\.)*"`},
diff --git a/ruki/lower.go b/ruki/lower.go
index db6dbe3..1c55ae4 100644
--- a/ruki/lower.go
+++ b/ruki/lower.go
@@ -3,8 +3,9 @@ package ruki
 import (
 	"fmt"
 	"strconv"
-	"strings"
 	"time"
+
+	"github.com/boolean-maybe/tiki/util/duration"
 )
 
 // lower.go converts participle grammar structs into clean AST types.
@@ -394,20 +395,9 @@ func parseDateLiteral(s string) (Expr, error) {
 }
 
 func parseDurationLiteral(s string) (Expr, error) {
-	// find where digits end and unit begins
-	i := 0
-	for i < len(s) && s[i] >= '0' && s[i] <= '9' {
-		i++
-	}
-	if i == 0 || i == len(s) {
-		return nil, fmt.Errorf("invalid duration literal %q", s)
-	}
-
-	val, err := strconv.Atoi(s[:i])
+	val, unit, err := duration.Parse(s)
 	if err != nil {
-		return nil, fmt.Errorf("invalid duration value in %q: %w", s, err)
+		return nil, err
 	}
-
-	unit := strings.TrimSuffix(s[i:], "s") // normalize "days" → "day"
 	return &DurationLiteral{Value: val, Unit: unit}, nil
 }
diff --git a/store/memory_store.go b/store/memory_store.go
index 8c385fc..6a43822 100644
--- a/store/memory_store.go
+++ b/store/memory_store.go
@@ -6,6 +6,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/boolean-maybe/tiki/config"
 	"github.com/boolean-maybe/tiki/store/internal/git"
 	"github.com/boolean-maybe/tiki/task"
 )
@@ -19,6 +20,7 @@ type InMemoryStore struct {
 	tasks          map[string]*task.Task
 	listeners      map[int]ChangeListener
 	nextListenerID int
+	idGenerator    func() string // injectable for testing; defaults to config.GenerateRandomID
 }
 
 func normalizeTaskID(id string) string {
@@ -31,6 +33,7 @@ func NewInMemoryStore() *InMemoryStore {
 		tasks:          make(map[string]*task.Task),
 		listeners:      make(map[int]ChangeListener),
 		nextListenerID: 1, // Start at 1 to avoid conflict with zero-value sentinel
+		idGenerator:    config.GenerateRandomID,
 	}
 }
 
@@ -222,22 +225,38 @@ func (s *InMemoryStore) GetGitOps() git.GitOps {
 	return nil
 }
 
-// NewTaskTemplate returns a new task with hardcoded defaults.
-// MemoryStore doesn't load templates from files.
+const maxIDAttempts = 100
+
+// NewTaskTemplate returns a new task with hardcoded defaults and an auto-generated ID.
 func (s *InMemoryStore) NewTaskTemplate() (*task.Task, error) {
-	task := &task.Task{
-		ID:          "", // Caller must set ID
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	var taskID string
+	for range maxIDAttempts {
+		taskID = normalizeTaskID(fmt.Sprintf("TIKI-%s", s.idGenerator()))
+		if _, exists := s.tasks[taskID]; !exists {
+			break
+		}
+		taskID = "" // mark as failed so we can detect exhaustion
+	}
+	if taskID == "" {
+		return nil, fmt.Errorf("failed to generate unique task ID after %d attempts", maxIDAttempts)
+	}
+
+	t := &task.Task{
+		ID:          taskID,
 		Title:       "",
 		Description: "",
 		Type:        task.TypeStory,
 		Status:      task.DefaultStatus(),
-		Priority:    7, // Match embedded template default
+		Priority:    7, // match embedded template default
 		Points:      1,
 		Tags:        []string{"idea"},
 		CreatedAt:   time.Now(),
 		CreatedBy:   "memory-user",
 	}
-	return task, nil
+	return t, nil
 }
 
 // ensure InMemoryStore implements Store
diff --git a/store/memory_store_test.go b/store/memory_store_test.go
index 874e027..a7fd0ee 100644
--- a/store/memory_store_test.go
+++ b/store/memory_store_test.go
@@ -1,6 +1,7 @@
 package store
 
 import (
+	"strings"
 	"testing"
 	"time"
 
@@ -331,6 +332,12 @@ func TestInMemoryStore_NewTaskTemplate(t *testing.T) {
 	if err != nil {
 		t.Fatalf("NewTaskTemplate() error = %v", err)
 	}
+	if !strings.HasPrefix(tmpl.ID, "TIKI-") || len(tmpl.ID) != 11 {
+		t.Errorf("ID = %q, want TIKI-XXXXXX format (11 chars)", tmpl.ID)
+	}
+	if tmpl.ID != strings.ToUpper(tmpl.ID) {
+		t.Errorf("ID = %q, should be uppercased", tmpl.ID)
+	}
 	if tmpl.Priority != 7 {
 		t.Errorf("Priority = %d, want 7", tmpl.Priority)
 	}
@@ -348,6 +355,50 @@ func TestInMemoryStore_NewTaskTemplate(t *testing.T) {
 	}
 }
 
+func TestInMemoryStore_NewTaskTemplateCollision(t *testing.T) {
+	s := NewInMemoryStore()
+
+	// pre-populate store with a task that will collide
+	_ = s.CreateTask(&taskpkg.Task{ID: "TIKI-AAAAAA", Title: "existing"})
+
+	callCount := 0
+	s.idGenerator = func() string {
+		callCount++
+		if callCount == 1 {
+			return "aaaaaa" // will collide (normalized to TIKI-AAAAAA)
+		}
+		return "bbbbbb" // will succeed
+	}
+
+	tmpl, err := s.NewTaskTemplate()
+	if err != nil {
+		t.Fatalf("NewTaskTemplate() error = %v", err)
+	}
+	if tmpl.ID != "TIKI-BBBBBB" {
+		t.Errorf("ID = %q, want TIKI-BBBBBB (should skip collision)", tmpl.ID)
+	}
+	if callCount != 2 {
+		t.Errorf("idGenerator called %d times, want 2 (one collision + one success)", callCount)
+	}
+}
+
+func TestInMemoryStore_NewTaskTemplateExhaustion(t *testing.T) {
+	s := NewInMemoryStore()
+
+	// pre-populate with the only ID the generator will ever produce
+	_ = s.CreateTask(&taskpkg.Task{ID: "TIKI-AAAAAA", Title: "existing"})
+
+	s.idGenerator = func() string { return "aaaaaa" }
+
+	_, err := s.NewTaskTemplate()
+	if err == nil {
+		t.Fatal("expected error for ID exhaustion, got nil")
+	}
+	if !strings.Contains(err.Error(), "failed to generate unique task ID") {
+		t.Errorf("unexpected error message: %v", err)
+	}
+}
+
 func TestInMemoryStore_GetAllTasks(t *testing.T) {
 	t.Run("empty store returns empty slice", func(t *testing.T) {
 		s := NewInMemoryStore()
diff --git a/util/duration/duration.go b/util/duration/duration.go
new file mode 100644
index 0000000..6aa38bd
--- /dev/null
+++ b/util/duration/duration.go
@@ -0,0 +1,86 @@
+package duration
+
+import (
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// unit pairs a canonical short name with its time.Duration equivalent.
+type unit struct {
+	name     string
+	duration time.Duration
+}
+
+// units is the canonical, immutable list of supported duration units.
+var units = [...]unit{
+	{"sec", time.Second},
+	{"min", time.Minute},
+	{"hour", time.Hour},
+	{"day", 24 * time.Hour},
+	{"week", 7 * 24 * time.Hour},
+	{"month", 30 * 24 * time.Hour},
+	{"year", 365 * 24 * time.Hour},
+}
+
+var unitMap map[string]time.Duration
+
+func init() {
+	unitMap = make(map[string]time.Duration, len(units))
+	for _, u := range units {
+		unitMap[u.name] = u.duration
+	}
+}
+
+// Parse splits a duration string like "30min" or "2days" into its numeric
+// value and canonical unit name. Plural trailing "s" is stripped.
+func Parse(s string) (int, string, error) {
+	i := 0
+	for i < len(s) && s[i] >= '0' && s[i] <= '9' {
+		i++
+	}
+	if i == 0 || i == len(s) {
+		return 0, "", fmt.Errorf("invalid duration literal %q", s)
+	}
+
+	val, err := strconv.Atoi(s[:i])
+	if err != nil {
+		return 0, "", fmt.Errorf("invalid duration value in %q: %w", s, err)
+	}
+
+	unit := strings.TrimSuffix(s[i:], "s")
+	if !IsValidUnit(unit) {
+		return 0, "", fmt.Errorf("unknown duration unit %q in %q", unit, s)
+	}
+	return val, unit, nil
+}
+
+// ToDuration converts a value and canonical unit name to a time.Duration.
+func ToDuration(value int, unit string) (time.Duration, error) {
+	d, ok := unitMap[unit]
+	if !ok {
+		return 0, fmt.Errorf("unknown duration unit %q", unit)
+	}
+	return time.Duration(value) * d, nil
+}
+
+// IsValidUnit reports whether name is a recognized duration unit.
+func IsValidUnit(name string) bool {
+	_, ok := unitMap[name]
+	return ok
+}
+
+// Pattern returns a regex alternation of all unit names, sorted longest-first
+// so that greedy matching prefers "month" over "min".
+func Pattern() string {
+	names := make([]string, len(units))
+	for i, u := range units {
+		names[i] = u.name
+	}
+	sort.Slice(names, func(i, j int) bool {
+		return len(names[i]) > len(names[j])
+	})
+	return strings.Join(names, "|")
+}
diff --git a/util/duration/duration_test.go b/util/duration/duration_test.go
new file mode 100644
index 0000000..da83e3c
--- /dev/null
+++ b/util/duration/duration_test.go
@@ -0,0 +1,175 @@
+package duration
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestParse(t *testing.T) {
+	tests := []struct {
+		input    string
+		wantVal  int
+		wantUnit string
+	}{
+		{"1sec", 1, "sec"},
+		{"10secs", 10, "sec"},
+		{"1min", 1, "min"},
+		{"30mins", 30, "min"},
+		{"1hour", 1, "hour"},
+		{"2hours", 2, "hour"},
+		{"1day", 1, "day"},
+		{"7days", 7, "day"},
+		{"1week", 1, "week"},
+		{"3weeks", 3, "week"},
+		{"1month", 1, "month"},
+		{"6months", 6, "month"},
+		{"1year", 1, "year"},
+		{"2years", 2, "year"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			val, unit, err := Parse(tt.input)
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if val != tt.wantVal {
+				t.Errorf("value = %d, want %d", val, tt.wantVal)
+			}
+			if unit != tt.wantUnit {
+				t.Errorf("unit = %q, want %q", unit, tt.wantUnit)
+			}
+		})
+	}
+}
+
+func TestParseErrors(t *testing.T) {
+	tests := []struct {
+		input string
+		desc  string
+	}{
+		{"", "empty string"},
+		{"min", "no digits"},
+		{"30", "no unit"},
+		{"30bogus", "unknown unit"},
+		{"0xAhour", "non-decimal digits"},
+		{"99999999999999999999sec", "integer overflow"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.desc, func(t *testing.T) {
+			_, _, err := Parse(tt.input)
+			if err == nil {
+				t.Fatal("expected error, got nil")
+			}
+		})
+	}
+}
+
+func TestToDuration(t *testing.T) {
+	tests := []struct {
+		unit string
+		want time.Duration
+	}{
+		{"sec", time.Second},
+		{"min", time.Minute},
+		{"hour", time.Hour},
+		{"day", 24 * time.Hour},
+		{"week", 7 * 24 * time.Hour},
+		{"month", 30 * 24 * time.Hour},
+		{"year", 365 * 24 * time.Hour},
+	}
+	for _, tt := range tests {
+		t.Run(tt.unit, func(t *testing.T) {
+			got, err := ToDuration(1, tt.unit)
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if got != tt.want {
+				t.Errorf("ToDuration(1, %q) = %v, want %v", tt.unit, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestToDurationMultiplier(t *testing.T) {
+	tests := []struct {
+		value int
+		unit  string
+		want  time.Duration
+	}{
+		{3, "sec", 3 * time.Second},
+		{5, "min", 5 * time.Minute},
+		{2, "hour", 2 * time.Hour},
+		{5, "day", 5 * 24 * time.Hour},
+		{3, "week", 3 * 7 * 24 * time.Hour},
+		{2, "month", 2 * 30 * 24 * time.Hour},
+		{4, "year", 4 * 365 * 24 * time.Hour},
+	}
+	for _, tt := range tests {
+		t.Run(fmt.Sprintf("%d_%s", tt.value, tt.unit), func(t *testing.T) {
+			got, err := ToDuration(tt.value, tt.unit)
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if got != tt.want {
+				t.Errorf("ToDuration(%d, %q) = %v, want %v", tt.value, tt.unit, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestToDurationUnknownUnit(t *testing.T) {
+	_, err := ToDuration(1, "unknown")
+	if err == nil {
+		t.Fatal("expected error for unknown unit")
+	}
+}
+
+func TestIsValidUnit(t *testing.T) {
+	for _, u := range units {
+		if !IsValidUnit(u.name) {
+			t.Errorf("IsValidUnit(%q) = false, want true", u.name)
+		}
+	}
+	if IsValidUnit("minute") {
+		t.Error("IsValidUnit(\"minute\") = true, want false")
+	}
+	if IsValidUnit("bogus") {
+		t.Error("IsValidUnit(\"bogus\") = true, want false")
+	}
+}
+
+func TestPatternContainsAllUnits(t *testing.T) {
+	p := Pattern()
+	for _, u := range units {
+		if !strings.Contains(p, u.name) {
+			t.Errorf("Pattern() missing unit %q", u.name)
+		}
+	}
+}
+
+func TestPatternRegexMatchesAllUnits(t *testing.T) {
+	re := regexp.MustCompile(`^\d+(?:` + Pattern() + `)s?$`)
+	for _, u := range units {
+		singular := "1" + u.name
+		if !re.MatchString(singular) {
+			t.Errorf("pattern does not match %q", singular)
+		}
+		plural := "1" + u.name + "s"
+		if !re.MatchString(plural) {
+			t.Errorf("pattern does not match %q", plural)
+		}
+	}
+}
+
+func TestPatternLongestFirst(t *testing.T) {
+	p := Pattern()
+	// "month" must appear before "min" so regex matches greedily
+	monthIdx := strings.Index(p, "month")
+	minIdx := strings.Index(p, "min")
+	if monthIdx > minIdx {
+		t.Errorf("Pattern() has 'min' before 'month': %s", p)
+	}
+}