# square/tape

A lightning fast, transactional, file-based FIFO for Android and Java.

Repository: https://github.com/square/tape
Canonical: https://ross.abutalabs.com/products/square-tape
Homepage: https://square.github.io/tape/
Language: Java
License: Apache-2.0
License Family: permissive
Archived: true
Last push: 2023-03-18T23:20:25+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 5105, "days_push": 1264, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2455, forks 282 (observed 2026-08-28T04:06:53.170826+00:00)

## What it is
Tape is a Java library from Square providing QueueFile, a fast, transactional, file-based FIFO queue with atomic O(1) add/remove operations, plus ObjectQueue for arbitrary objects backed by disk or memory. It is designed to survive process and system crashes, making it well suited for reliable background task queuing on Android.

## Use cases
- persist a task queue that survives app crashes on Android
- reliable background upload queue for photos
- file-based FIFO queue in Java
- queue work items to disk before processing
- durable message queue without a database

## When to choose
- you need a small, dependency-free persistent FIFO on Android or the JVM
- you need crash-safe, atomic queue operations backed by a single file
- you want an in-memory or disk-backed object queue with a simple API

## When to avoid
- you need a distributed or multi-consumer message broker
- your file system lacks atomic segment writes and you need power-loss durability
- you need high-throughput concurrent producers and consumers

## Facets
- artifact type: library
- maturity: maintenance
- function: message-queue, serialization, file-system
- domain: mobile-development, developer-tools, files
- platform: jvm
- tags: fifo-queue, persistent-queue, transactional-io, android, java

## Member repositories
- square/tape (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:53.170826+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:30:06.321353+00:00, confidence not recorded.
  - readme: https://github.com/square/tape (fetched 2026-08-28T04:06:53.170826+00:00, sha 68eb38e6c011)
  - homepage: https://square.github.io/tape/ (fetched 2026-08-29T10:11:18.859707+00:00, sha cc0fe2da457e)
- Data as of 2026-08-30T08:39:29.467469+00:00.