diff --git a/.gitignore b/.gitignore
index 59c239b..73d9665 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 .opencode
+/poiesis
diff --git a/AGENTS.md b/AGENTS.md
index d7dfd25..1231393 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -106,6 +106,62 @@ functions.RegisterAsyncFunction[FetchArgs, *FetchResult]("fetch", Fetch)
 - `github.com/evanw/esbuild/pkg/api` - TypeScript transpilation
 - `github.com/fastschema/qjs` - JavaScript execution (CGO-free QuickJS runtime)
 - `github.com/stretchr/testify/assert` - Test assertions
+- `github.com/sirupsen/logrus` - Logging framework
+
+## Logging Practices
+
+### Primary Logger
+
+Use `github.com/sirupsen/logrus` as the primary logging framework throughout the codebase.
+
+### Error Handling
+
+- Use `WithError(err)` when logging errors to include the error context
+- Every error should eventually be logged somewhere appropriate in the call chain
+- Don't log on every error condition - find the appropriate upstream logging location
+- Use structured logging with context fields when relevant for debugging
+
+### Structured Logging
+
+- Use `WithField(key, value)` for contextual information
+- Use `WithFields(fields)` when adding multiple fields
+- Field names must be in camelCase (e.g., `WithField("filePath", path)`)
+- Only use WithField(s) when the field is relevant and helpful for debugging issues
+- Tag services with their name: `logger.WithField("service", "runtime")`
+
+### Example Usage
+
+```go
+import "github.com/sirupsen/logrus"
+
+func New(ctx context.Context) (*Runtime, error) {
+    logger := logrus.New()
+    r := &Runtime{logger: logger.WithField("service", "runtime")}
+
+    rt, err := qjs.New(r.opts)
+    if err != nil {
+        logger.WithError(err).Error("Failed to create QuickJS context")
+        return nil, err
+    }
+
+    return r, nil
+}
+
+func (r *Runtime) ExecuteFile(filePath string) error {
+    data, err := os.ReadFile(filePath)
+    if err != nil {
+        return fmt.Errorf("read file %s: %w", filePath, err)
+    }
+
+    result, err := r.ctx.Eval("code.ts", qjs.Code(string(data)))
+    if err != nil {
+        r.logger.WithField("filePath", filePath).WithError(err).Error("Execution failed")
+        return err
+    }
+
+    return nil
+}
+```
 
 ## Code Conventions
 
diff --git a/cmd/poiesis/main.go b/cmd/poiesis/main.go
index af71dd6..74981d6 100644
--- a/cmd/poiesis/main.go
+++ b/cmd/poiesis/main.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 
+	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 	"reichard.io/poiesis/internal/runtime"
 )
@@ -13,23 +14,26 @@ var runCmd = &cobra.Command{
 	Use:   "execute [file]",
 	Short: "Transpile and execute TypeScript code",
 	Long: `Poiesis transpiles TypeScript to JavaScript using esbuild and executes it with QuickJS.
-It also provides a builtin system for exposing Go functions to TypeScript.`,
+	It also provides a builtin system for exposing Go functions to TypeScript.`,
 	Args: cobra.MaximumNArgs(1),
 	Run: func(cmd *cobra.Command, args []string) {
 		ctx := context.Background()
-		rt, err := runtime.New(ctx)
+		logger := logrus.New()
+		rt, err := runtime.New(ctx, runtime.WithLogger(logger))
 		if err != nil {
+			logger.WithError(err).Error("Failed to create runtime")
 			fmt.Fprintf(os.Stderr, "Failed to create runtime: %v\n", err)
 			os.Exit(1)
 		}
 
 		if len(args) == 0 {
 			fmt.Fprintln(os.Stderr, "Usage: poiesis execute [file]")
-			cmd.Help()
+			_ = cmd.Help()
 			os.Exit(1)
 		}
 
 		if err := rt.RunFile(args[0]); err != nil {
+			logger.WithError(err).Error("Failed to run file")
 			fmt.Fprintf(os.Stderr, "Failed to run file: %v\n", err)
 			os.Exit(1)
 		}
@@ -41,8 +45,10 @@ var typesCmd = &cobra.Command{
 	Short: "Print TypeScript type declarations",
 	Run: func(cmd *cobra.Command, args []string) {
 		ctx := context.Background()
-		rt, err := runtime.New(ctx)
+		logger := logrus.New()
+		rt, err := runtime.New(ctx, runtime.WithLogger(logger))
 		if err != nil {
+			logger.WithError(err).Error("Failed to create runtime")
 			fmt.Fprintf(os.Stderr, "Failed to create runtime: %v\n", err)
 			os.Exit(1)
 		}
diff --git a/go.mod b/go.mod
index 6117202..5bb09ff 100644
--- a/go.mod
+++ b/go.mod
@@ -12,6 +12,7 @@ require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/sirupsen/logrus v1.9.4 // indirect
 	github.com/spf13/cobra v1.10.2 // indirect
 	github.com/spf13/pflag v1.0.9 // indirect
 	github.com/tetratelabs/wazero v1.9.0 // indirect
diff --git a/go.sum b/go.sum
index 9ff65dd..c820898 100644
--- a/go.sum
+++ b/go.sum
@@ -10,6 +10,8 @@ github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLf
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/sirupsen/logrus v1.9.4 h1:TsZE7l11zFCLZnZ+teH4Umoq5BhEIfIzfRDZ1Uzql2w=
+github.com/sirupsen/logrus v1.9.4/go.mod h1:ftWc9WdOfJ0a92nsE2jF5u5ZwH8Bv2zdeOC42RjbV2g=
 github.com/spf13/cobra v1.10.2 h1:DMTTonx5m65Ic0GOoRY2c16WCbHxOOw6xxezuLaBpcU=
 github.com/spf13/cobra v1.10.2/go.mod h1:7C1pvHqHw5A4vrJfjNwvOdzYu0Gml16OCs2GRiTUUS4=
 github.com/spf13/pflag v1.0.9 h1:9exaQaMOCwffKiiiYk6/BndUBv+iRViNW+4lEMi0PvY=
diff --git a/internal/runtime/options.go b/internal/runtime/options.go
index 9213669..a0a8b64 100644
--- a/internal/runtime/options.go
+++ b/internal/runtime/options.go
@@ -1,6 +1,10 @@
 package runtime
 
-import "io"
+import (
+	"io"
+
+	"github.com/sirupsen/logrus"
+)
 
 type RuntimeOption func(*Runtime)
 
@@ -17,3 +21,9 @@ func WithStderr(stderr io.Writer) RuntimeOption {
 		r.opts.Stderr = stderr
 	}
 }
+
+func WithLogger(logger *logrus.Logger) RuntimeOption {
+	return func(r *Runtime) {
+		r.logger = logger.WithField("service", "runtime")
+	}
+}
diff --git a/internal/runtime/runtime.go b/internal/runtime/runtime.go
index e068fb6..478c89a 100644
--- a/internal/runtime/runtime.go
+++ b/internal/runtime/runtime.go
@@ -8,6 +8,7 @@ import (
 
 	"github.com/evanw/esbuild/pkg/api"
 	"github.com/fastschema/qjs"
+	"github.com/sirupsen/logrus"
 
 	"reichard.io/poiesis/internal/functions"
 	_ "reichard.io/poiesis/internal/stdlib"
@@ -18,11 +19,13 @@ type Runtime struct {
 	opts      qjs.Option
 	funcs     map[string]functions.Function
 	typeDecls map[string]string
+	logger    *logrus.Entry
 }
 
 func New(ctx context.Context, opts ...RuntimeOption) (*Runtime, error) {
 	// Create Runtime
-	r := &Runtime{opts: qjs.Option{Context: ctx}}
+	logger := logrus.New()
+	r := &Runtime{opts: qjs.Option{Context: ctx}, logger: logger.WithField("service", "runtime")}
 	for _, opt := range opts {
 		opt(r)
 	}
@@ -30,12 +33,14 @@ func New(ctx context.Context, opts ...RuntimeOption) (*Runtime, error) {
 	// Create QuickJS Context
 	rt, err := qjs.New(r.opts)
 	if err != nil {
+		logger.WithError(err).Error("Failed to create QuickJS context")
 		return nil, err
 	}
 	r.ctx = rt.Context()
 
 	// Populate Globals
 	if err := r.populateGlobals(); err != nil {
+		logger.WithError(err).Error("Failed to populate globals")
 		return nil, err
 	}
 
@@ -62,6 +67,7 @@ func (r *Runtime) populateGlobals() error {
 			r.ctx.SetAsyncFunc(name, func(this *qjs.This) {
 				qjsVal, err := callFunc(this, fn)
 				if err != nil {
+					r.logger.WithError(err).Errorf("Async function %s failed", name)
 					_ = this.Promise().Reject(this.Context().NewError(err))
 					return
 				}