JAIPilot

Ship better Java with your coding agent.

JAIPilot helps Codex and Claude Code clean, test, review, modernize, and optimize real Java repositories without drifting into unnecessary code or unproved changes.

By default, your agent runs Java builds, tests, analysis, profiling, and benchmarks on a ready remote Java machine whenever the task does not require laptop-only access or state.

JAIPilot does not replace your coding agent or add another AI. It gives your agent focused Java workflows, remote compute, and one rule: show evidence, not confidence.

Install and run

Codex

codex plugin marketplace add JAIPilot/jaipilot
codex plugin add jaipilot@jaipilot

Claude Code

/plugin marketplace add JAIPilot/jaipilot
/plugin install jaipilot@jaipilot

Open a Java repository and ask:

Make my current Java changes production-ready without changing their behavior. Add missing tests,
remove unnecessary code, improve only performance you can measure, and run the full verification.
Use JAIPilot Remote for substantial Java commands unless this work needs my laptop.

The Java skills work locally as soon as the plugin is installed. When remote execution is useful, your agent asks before uploading the current tracked and unignored Git files. Approve the upload and sign in when prompted; the agent handles packaging, integrity checking, upload, execution, logs, and workspace deletion. You do not create an archive, configure a VM, provide an API key, or copy files manually. .git, ignored files, and remote edits are never transferred back automatically.

If packaging or upload cannot be verified, JAIPilot does not create the workspace. Your agent must show the failing step instead of silently uploading a different source tree.

JAIPilot vs no JAIPilot

The original Petclinic PR already had a green build. JAIPilot reviewed that exact head and produced this companion change:

The important result is not simply “more tests.” Without JAIPilot, the build passed while the new behavior had zero coverage and unused code remained. With JAIPilot, the same behavior stayed green, the edge cases became executable tests, and production code became smaller.

The comparison uses the original PR head and JAIPilot's direct child commit, clean worktrees, the same ./mvnw -q clean verify command, and fresh JaCoCo 0.8.14 reports.

Measured performance: Apache Calcite

On skrcode/calcite at exact commit d3a5d8d, JAIPilot profiled Calcite's existing DefaultDirectedGraphBenchmark.removeAllVertices{10,50,90}Benchmark. The 50% workload attributed 31.1% of runnable samples to Collection.removeIf: the implementation scanned the complete global edge set once for every removed vertex.

The candidate changed two files (+28/-5), removed the repeated scans, and added behavior tests for the majority-removal and self-loop paths. Lower JMH scores are better:

Baseline and candidate ran on the same 4 CPU/8 GiB remote workspace with the same Temurin JDK 17, built JMH jar, command, and workload. Each row contains 21 measured observations: seven forks with three measured iterations per fork after warm-up. The identical focused command passed 15/15 tests before and after the production edit. A fresh exact-SHA :core:clean :core:check then completed 16,644 tests with 0 failures and 155 skips, and the tested remote diff matched the local candidate digest.

This is a controlled result for Calcite's existing graph-removal workloads, not a claim that every Java workload becomes faster.

Measured performance: OpenTelemetry Java

On skrcode/opentelemetry-java at exact commit 35636ae, JAIPilot found that immutable attribute sets were sorted by key name during construction but still used a full linear scan for every lookup. This matters at the default span limit of 128 attributes.

The three-file draft change preserves the small-set and first-four-entry fast path, then uses binary search for the rest. It also adds a large-set behavior test and a repository-native JMH benchmark. Lower values are better:

Baseline and candidate ran in the same 4 CPU/8 GiB remote workspace with Temurin JDK 21, the same JMH jar, command, warm-up, and workload. Each row has 21 observations. The new focused behavior test passed before and after the production edit; a clean :api:all:check passed all 147 tasks including Animal Sniffer, Checkstyle, Spotless, tests, and japicmp. The tested remote Git delta matched the local candidate digest. The Value workload still allocates about 16 B/op; JAIPilot reports the lookup-time win without claiming that allocation disappeared.

Measured performance: Micrometer

On skrcode/micrometer at exact commit 22207bf, JAIPilot found that adding or replacing one Tag or KeyValue went through temporary varargs and iterable merge machinery even though the backing arrays were already sorted.

The six-file draft change adds a bounded binary-search merge for the single-value overloads, behavior tests, and four workloads in Micrometer's existing JMH module:

Single-value insertion reduced median allocation by 17.6% and p95 allocation by 46.2%. Its median latency improved by only 6.7–8.9%, below JAIPilot's 10% shared-hardware threshold, so it is not presented as a speed win. The same-workspace experiment used 21 observations per workload; 92 focused tests and the final clean scoped build passed, with 1,132 tests, zero failures, and the remote production diff matching the local digest.

Measured database work: Petclinic

Read the full README on GitHub →