LogTape is a zero-dependency logging library for JavaScript and TypeScript that runs unchanged across Deno, Node.js, Bun, browsers, and edge functions, and it is designed first for library authors who need to emit logs without imposing configuration on the applications that install them.

What it is

LogTape is an open-source logging library written in TypeScript and published under the MIT licence. It lives in the JavaScript and TypeScript ecosystem, where it is distributed through two package registries: JSR as @logtape/logtape and npm as @logtape/logtape. The project is a monorepo, and the main package @logtape/logtape provides the core logging functionality, with additional packages sitting alongside it. The homepage at logtape.org hosts the manual, including the installation guide, structured logging guide, category guide, redaction guide, sink guide, and integration guide.

The concrete problem it solves is the configuration deadlock in conventional loggers. Traditional loggers expect the application to configure logging before anything is logged, which means a library that wants to record diagnostics either forces its own configuration on the host application or stays silent. LogTape takes the library-first position instead: a library can call the logger safely with no setup at all, and the application retains full control over level, sinks, and output. That is the specific thing it replaces, in place of loggers that treat the application as the sole legitimate owner of logging configuration.

Key capabilities

• Zero dependencies, so LogTape adds nothing to the dependency graph of the package that uses it.
• Library-first design documented at the manual's library page, letting a library provide logging capability to its users without configuring it.
• Universal runtime support across Deno, Node.js, Bun, browsers, and edge functions, with the same code in each environment.
• Structured logging, so messages carry structured data rather than only a formatted string.
• Hierarchical categories that manage loggers, where setting the level at one point in the category hierarchy controls verbosity for the levels beneath it.
• Template literals for log messages, allowing placeholders and values in the call site.
• Built-in data redaction using pattern-based and field-based approaches to strip sensitive information from logs.
• Small sinks API, described as dead simple to extend with your own sinks.
• First-class framework integrations with Express, Fastify, GraphQL Yoga, Hono, Koa, and Drizzle ORM, covering automatic HTTP request logging, GraphQL server logging, and database query logging.

Who uses it and how

• Library maintainers who ship a package to unknown consumers and want diagnostics available without demanding that consumers configure a logger first.
• Application teams that need to own log level, sink routing, and redaction policy across every dependency at once.
• Projects deployed to more than one runtime, since the same logging calls work on Deno, Node.js, Bun, browsers, and edge functions without code changes.
• Teams subject to data-handling rules that need pattern-based or field-based redaction applied before entries leave the process.
• Services built on Express, Fastify, GraphQL Yoga, Hono, Koa, or Drizzle ORM that want automatic HTTP request, GraphQL server, or database query logging.

Getting started

Installation is by package manager against the published package: deno add jsr:@logtape/logtape for Deno, or npm add @logtape/logtape, pnpm add @logtape/logtape, yarn add @logtape/logtape, or bun add @logtape/logtape elsewhere, with further detail in the installation manual on logtape.org.

How it compares

The provided facts name no paid products that LogTape replaces, and they name no comparable logging libraries. On the evidence available here, it stands alone in this registry.

When to use it — and when not to

A self-hoster operates nothing extra for LogTape itself, because there is no server, database, or SMTP component to run, and no hosted tier is described in the facts; output goes to whatever sinks the application chooses to attach. Pick it when the priority is a dependency-free logger that a library can safely call and an application can fully control. Do not pick it if the requirement is a turnkey hosted log aggregation service with dashboards and alerting bundled in, since the facts describe a library and manual only, and the README excerpt supplied here is truncated before the package list is complete.

deno add jsr:@logtape/logtape  # for Deno
npm  add     @logtape/logtape  # for npm
pnpm add     @logtape/logtape  # for pnpm
yarn add     @logtape/logtape  # for Yarn
bun  add     @logtape/logtape  # for Bun