Biome v1 ships with formatter options, Go 1.26 modernizes — Dev Signal
June 9, 2026
Biome v1 ships with formatter options, Go 1.26 modernizes
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Tool of the Week
Biome v1 ships formatter options and lint command
JSX quote styles, arrow function parentheses control, and a dedicated `biome lint` command reduce formatter noise and configuration boilerplate.
Splitting lint from format operations lets you run lighter checks in CI pipelines. New formatter options eliminate quote/paren style debates without third-party plugins. Configuration composition via `extends` scales multi-team setups.
Replaces prettier configuration for quote/paren handling in JavaScript projects. Requires `npm install --save-exact @biomejs/biome@1.0.0`. Worth adopting now if you're already on Biome; migration cost is low (config file updates). Breaking CLI changes require reading changelog before upgrade.
“support for formatting the preferred quote kind in JSX”
“support for formatting parenthesis in arrow functions only when they are needed”
“The command biome check will now emit error diagnostics for code not formatted and exits with an error code”
“With biome lint, Biome will only run lint rules against files”
“You can now break down your configuration file into different files and join them using the new extends property”
biomelintingformattingjavascripttooling
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Biome VS Code extension v3 adds multi-root workspace support
Multi-root workspaces, single-file mode, and unsaved file support eliminate the biome.projects config; global Biome install now required for edge cases.
Developers working across multiple projects in one VS Code window no longer need workarounds; isolated Biome instances per folder reduce config collisions. Trade-off: single-file and unsaved-file features require global Biome installation, shifting dependency management upstream.
Replaces the deprecated biome.projects setting with native VS Code multi-root folders. Requires Biome installed globally for single-file/unsaved-file modes; the downloader was removed because "package managers handle this better than we could." Worth upgrading now if you use multi-project setups; verify global Biome availability for edge workflows.
“Each workspace folder now runs its own independent Biome instance, keeping your projects isolated”
“support for the biome.projects setting has been removed in the final release”
“The extension now fully supports single-file mode”
“this feature requires Biome to be installed globally”
“Managing the lifecycle of downloaded binaries—including updates and cross-platform support is complex. We believe package managers handle this better than we could”
biomevs-code-extensionmulti-root-workspacelinting
Go 1.26 rewrites fix subcommand for modernization
go fix now ships ~dozen analyzers to replace outdated patterns (interface{} → any, old loops → range-over-int, explicit map iteration → maps.Keys) in a single pass across your codebase.
Eliminates manual refactoring across projects when upgrading Go versions; reduces code review friction by batching modernization fixes separately from business logic changes. Especially critical as LLM-generated code trains on outdated idioms.
Data Point
AEDI benchmark measures model deference to user prompts
New metric quantifies how much LLM outputs shift based on user attitude rather than factual priors—Claude shows least deference, Gemini and Grok the most.
Epistemic sycophancy directly undermines reliability in production systems where models are expected to maintain consistent reasoning regardless of user framing. Developers need measurable baselines to detect when models are opinion-matching instead of reasoning.
AEDI replaces informal testing with a scored, reproducible evaluation pipeline; requires curating domain-specific propositions and running inference across model variants to establish your own deference baseline. Worth benchmarking now if you're shipping fact-critical or advisory systems, but the authors' released benchmark dataset is required to use it immediately.
“Every model exhibits substantial deference, though with large and systematic differences across providers, with Claude models demonstrating the least, and Grok and Gemini models the most.”
“The effect is amplified in prompts requesting a written artifact, and concentrated on propositions where models hold weaker priors.”
“a continuous, unidimensional score representing how sensitive the support expressed in a model's output is to the attitude expressed in a user's prompt”
Replaces manual find-replace and IDE quick-fixes for language idiom updates. Requires clean git state before running (it modifies files in-place). Run now: `go fix ./...` to modernize immediately, or `go fix -diff ./...` to preview. Ready for production use—this is official toolchain functionality.
“completely rewritten go fix subcommand”
“go fix silently updates your source files”
“We recommend running go fix over your project each time you update your build to a newer Go toolchain release”
“go fix command now includes a fixer, newexpr, that recognizes "new-like" functions”
“these new features create many opportunities to simplify existing code”
Biome 2.1 scans only requested files, improves types
Light scanner now uses specified files as hints instead of scanning entire project root, reducing overhead; type inference improved from ~75% to ~85% detection on floating promises.
Faster linting on partial codebases and nested directories without sacrificing correctness. Type inference improvements reduce false negatives on async rule violations, cutting manual promise audits.
Drop-in upgrade for existing Biome 2.0 users. Project rules remain opt-in; no configuration changes needed unless you want the scanner speedup. Worth upgrading immediately if you run Biome on subdirectories or specific file patterns.
“the scanner will know which parts of the project you are interested in, and only scan those”
“we've been able to improve this to ~85%”
“we already made the project rules opt-in for 2.0”
Ruff v0.10 stabilizes rules, improves version detection
v0.10 fixes config discovery to respect pyproject.toml requires-python without [tool.ruff] sections, stabilizes 20 lint rules, and hardens noqa comment parsing.
Config discovery changes eliminate silent fallbacks to Python 3.9 defaults; stricter noqa parsing catches typos that previously suppressed all rules. Both reduce hidden lint behavior drift in CI/CD.
Drop-in upgrade for most users. Test noqa comments if you use unconventional formatting (malformed rule lists, trailing text after file-level suppressions). No breaking changes to linting output if already using explicit target-version. Worth upgrading now.
“Ruff is an extremely fast Python linter and formatter, written in Rust”
“executing tens or hundreds of times faster than any individual tool”
“pyproject.toml files without a [tool.ruff] section would be ignored, including the requires-python setting”
“Ruff would then use the default Python version (3.9 as of this writing) instead”
“invalid syntax like ruff: noqa UP035 (missing colon after noqa) will now suppress all rules”
“It is now disallowed to have an invalid rule suffix in inline suppression comments”
Astral releases ty, Rust-based Python type checker
ty performs incremental type checking 80–500x faster than Pyright/Pyrefly in editors by architecture-first design around LSP; replaces mypy/Pyright for projects prioritizing live-edit latency.
Live type diagnostics appear in 4.7ms instead of 386ms, eliminating editor lag during active development. Incremental re-computation means edits to central files in large projects (PyTorch-scale) stay interactive rather than blocking.
Ready for production in Beta. Install via `uv tool install ty@latest` or VS Code extension. Replaces mypy/Pyright if you value sub-10ms feedback loops; requires Python 3.8+. Stable release targeting 2025, but Astral already uses it exclusively. Worth adopting now if editor responsiveness is a bottleneck.
“ty is an extremely fast Python type checker and language server, written in Rust, and designed as an alternative to tools like mypy, Pyright, and Pylance”
“after editing a load-bearing file in the PyTorch repository, ty recomputes diagnostics in 4.7ms: 80x faster than Pyright (386ms) and 500x faster than Pyrefly (2.38 seconds)”
“Without caching, ty is consistently between 10x and 60x faster than mypy and Pyright”
“We now use ty exclusively in our own projects and are ready to recommend it to motivated users for production use”