Dev Toolkit packs six focused transforms into one IDE-style pane. Paste input on the left, choose a mode, and copy structured output on the right. Clipboard heuristics can suggest Semver, Chmod, or Docker modes when the paste shape is obvious.

What you get

• semver-parse — major/minor/patch, prerelease, build metadata
• chmod-convert — octal ↔ symbolic (755 ↔ rwxr-xr-x)
• docker-compose — docker run → Compose services YAML snippet
• list-to-json — newline list → JSON string array
• json-to-list — JSON array → newline list
• columns-to-json — header CSV rows → JSON object array

Use this toolkit when

• You need a quick semver breakdown for release notes or CI gates
• You are translating permissions between octal docs and ls -l style
• You want a first-pass Compose file from a working docker run
• You are cleaning pasted lists into JSON for configs or mocks

Choose the mode that matches your input shape. Wrong mode is the most common failure.

Mode first, then paste — or paste and accept a clipboard suggestion when offered.

1. Select the mode tab that matches your task (Semver, Chmod, Docker Compose, or a list transform).
2. Paste input on the left. For Docker, start with docker run; for Columns → JSON, include a header row.
3. Read the right pane (and any detail blocks for Semver/Chmod).
4. Copy output into Compose files, docs, CI, or JSON Formatter for further edits.
5. If you see an error, check the mode-specific fix guides below — do not switch modes blindly without reshaping input.

Parses optional leading v, then major.minor.patch with optional -prerelease and +build metadata per a practical SemVer subset.

When to use

• Extract components for changelogs or feature flags
• Normalize v1.0.0 vs 1.0.0 before comparison tables
• Confirm prerelease/build strings before tagging

Common mistakes

• Two-part versions (1.2) fail — need major.minor.patch
• Ranges (^1.2.3, ~1.0) are not versions — strip range operators first
• Maven/CalVer strings may not match this pattern

Converts 3- or 4-digit octal (optional 0o prefix on symbolic path via digits) to rwx triplets, or symbolic rwxr-xr-x back to three octal digits. Detection: all-digit octal → symbolic; otherwise symbolic → octal.

When to use

• Translate Dockerfile chmod 755 examples into symbolic form for docs
• Decode ls -l permission strings into octal for scripts

Common mistakes

• Sticky/setuid high bits: 4-digit octal is accepted toward symbolic, but symbolic→octal emits three digits only
• Symbolic must be exactly nine characters of r/w/x/- in three groups
• Do not paste ls -l owner/group/name columns — permissions only

Tokenizes a docker run command and maps -e/--env, -p/--publish, -v/--volume, and --name into a Compose services snippet with image.

When to use

• Turn a working one-liner into a checked-in Compose starter
• Document local dependencies for teammates

Mapped flags

• -e / --env → environment list
• -p / --publish → ports list
• -v / --volume → volumes list
• --name → service key (default service)

Common mistakes

• Input must start with docker run
• Many flags are ignored (networks, restart, --rm, devices, gpus) — add them manually in Compose
• Image must be a non-flag token; missing image throws
• Complex shell quoting may need cleanup before paste

Three list-oriented modes cover the usual paste shapes between shells, JSON, and tiny CSV tables.

List → JSON

Splits on newlines, trims, drops blanks, emits a pretty-printed JSON string array. Use for allowlists and enum-like configs.

JSON → List

Requires a JSON array; joins elements with newlines via String(). Objects become [object Object] — stringify deliberately upstream if needed.

Columns → JSON

First line = comma-separated headers; following lines = values. Emits an array of objects. This is a simple split on commas — not a full RFC 4180 CSV parser. For quoted commas or large files, preview in CSV Viewer first, then use a dedicated JSON ↔ CSV tool.

CI printed v2.4.0-rc.3+exp.sha.5114f85 and you need components for a release checklist.

How Dev Toolkit solves it

1. Select Semver mode (or paste and accept the Semver clipboard hint).
2. Paste the version string.
3. Copy major/minor/patch and prerelease into the checklist; use Normalized for tags without the build metadata if required.

You avoid hand-splitting prerelease vs build and mis-tagging the release.

A README only documents docker run -p 8080:80 -e NODE_ENV=production --name web nginx:alpine. You want Compose for local multi-service work.

How Dev Toolkit solves it

1. Select Docker Compose mode.
2. Paste the full docker run line.
3. Copy the services YAML into docker-compose.yml.
4. Manually add networks, restart policies, and depends_on as needed.

You get a valid starter service block without rewriting ports/env/volumes by hand.

A teammate pasted emails or feature flags as messy lines; you need a JSON array for config.

How Dev Toolkit solves it

1. Select List → JSON.
2. Paste one value per line; blank lines are dropped.
3. Copy the JSON array into your config or through JSON Formatter.
4. Use JSON → List later if you need to diff in a text editor.

Clean round-trip between editor lists and JSON configs.

Symptoms: “Invalid semver — expected major.minor.patch”.

Why it happens

Input is not three numeric core segments, or includes range/operator syntax the parser rejects.

Diagnose

Trim the string. Ensure the shape is MAJOR.MINOR.PATCH with optional -pre and +build only.

Fixes

1. Change 1.2 → 1.2.0 if that matches intent.
2. Remove ^, ~, >= and spaces from range expressions; parse a single concrete version.
3. Drop surrounding quotes or git describe suffixes that are not SemVer build metadata.

Symptoms: Compose output missing networks, restart, or GPU settings; or errors about docker run / image.

Why it happens

The converter intentionally maps a subset of flags. Unmapped flags are skipped; malformed commands fail fast.

Diagnose

Confirm the line starts with docker run and ends with a detectable image token. List which flags you relied on beyond -e/-p/-v/--name.

Fixes

1. Fix the command prefix and image name first.
2. Add unmapped options manually under the generated service.
3. Simplify exotic quoting, then re-run the conversion.

Treat output as a scaffold, not a full Compose migration of every docker run feature.

• Using Columns → JSON on semicolon CSV or quoted commas — use CSV Viewer + JSON ↔ CSV instead
• Feeding JSON → List a non-array object
• Expecting chmod sticky bits to round-trip perfectly through symbolic → octal
• Assuming Docker mode preserves --rm, --network, or healthchecks
• Parsing semver ranges as single versions

• Pick the mode before pasting large blobs so you do not mis-transform data
• After Docker conversion, open the YAML in a Compose-aware editor and fill gaps
• Validate Semver output against your registry’s tag rules before cutting a release
• For tabular data with quotes, prefer CSV Viewer over Columns → JSON
• Keep secrets out of docker run -e pastes destined for tickets or git