diff --git a/app/src/cli/commands/run/run.ts b/app/src/cli/commands/run/run.ts
index ddfda010..1093e7c5 100644
--- a/app/src/cli/commands/run/run.ts
+++ b/app/src/cli/commands/run/run.ts
@@ -112,7 +112,14 @@ export async function makeAppFromEnv(options: Partial<RunOptions> = {}) {
          const config = await loadConfigFile(configFilePath);
          app = await makeConfigApp(config, options.server);
       } catch (e) {
-         console.error("Failed to load config:", e);
+         if (e instanceof ReferenceError && e.message === "Bun is not defined") {
+            console.error(
+               c.red("Your config imports from a Bun-specific adapter, but the CLI is running under Node."),
+               `\nRun with Bun instead:\n\n  ${c.cyan("bun node_modules/.bin/bknd")} ${c.dim(process.argv.slice(2).join(" "))}\n`,
+            );
+         } else {
+            console.error("Failed to load config:", e);
+         }
          process.exit(1);
       }
 
diff --git a/docs/content/docs/(documentation)/usage/cli.mdx b/docs/content/docs/(documentation)/usage/cli.mdx
index 838c169e..a34eba32 100644
--- a/docs/content/docs/(documentation)/usage/cli.mdx
+++ b/docs/content/docs/(documentation)/usage/cli.mdx
@@ -97,6 +97,12 @@ The `app` function is useful if you need a cross-platform way to access the envi
 
 TypeScript configuration files (`.ts`) are fully supported and work out of the box with `npx bknd run` — no additional flags or tools required.
 
+If your config imports from a runtime-specific adapter (e.g. `bknd/adapter/bun`), you need to run the CLI with that runtime:
+
+```sh
+bun node_modules/.bin/bknd run
+```
+
 ### Turso/LibSQL database
 
 To start an instance with a Turso/LibSQL database, run the following: