Assess React Native Migration

Assess React Native Migration

Produce a read-only migration decision. Diagnose the product and delivery system; do not execute the migration.

Establish Product Scope

Run the assessment from a workspace that exposes as many production client codebases as possible. The current checkout is not evidence that it contains the whole product.

Before assessing readiness:

1. Inspect the current repository and every workspace root available to the agent.
2. Infer supported client platforms from product documentation, CI, release configuration, workspace manifests, submodules, and references to sibling repositories.
3. Locate each production client codebase, including separate native iOS and Android repositories, app variants, and any web client relevant to staffing or proposed code sharing.
4. Record a platform inventory with the client, repository or path, evidence of product membership, and access status.

When iOS and Android are both supported, inspect both native codebases before recommending a path. If a codebase remains unavailable, mark its evidence unknown, state that the assessment covers only the accessible platforms, and lower confidence accordingly. Do not infer that a platform is unsupported merely because its project is absent from the current repository.

Scope gate: every supported production client is listed, and each codebase is accessible, explicitly unavailable, or confirmed not to exist.

First Response Gate

When the scope gate has not passed, the first response must be exactly:

**Question:** Where can I access the production codebase for each client platform this product supports, including iOS and Android if both exist?

**Why it matters:** A migration path based on only one platform can miss native dependencies, product behavior, and delivery constraints that change the decision.

After the scope gate passes, grill rather than survey when repository evidence is unavailable.

If the measurable migration driver is unknown, the first response must be exactly:

**Question:** What measurable delivery or business problem should a React Native migration solve?

**Why it matters:** This determines whether migration is relevant and which outcomes the assessment must test.

If the driver is already known, ask only the next highest-impact unknown using the same two-line shape. End the turn immediately after the question and reason. Do not add a preamble, questionnaire, recommendation, or implementation guidance.

Rules

• Treat every production app as a source of truth, including undocumented behavior.
• Inspect available code, CI, tests, release configuration, product documents, and runtime evidence before asking questions.
• Compare iOS and Android explicitly where their implementation, behavior, dependencies, delivery, or roadmap differ.
• Base product-wide claims only on evidence from every supported platform, or qualify their platform coverage.
• Label material claims observed, measured, reported, assumed, or unknown.
• Recommend from evidence, not an aggregate readiness score.
• Default to gathering evidence, not to brownfield, greenfield, or migration itself.
• Own the decision phase. Do not apply implementation skills or select Expo versus bare React Native before Path A is accepted.
• Count only React Native's marginal value over the current native system.
• Measure agents by accepted, verified work, not tokens, generated code, or pull requests.
• Make no universal claims about duration, cost, code sharing, agent productivity, or ROI.

Select the Evidence Mode

Use repository-backed assessment when source code or delivery artifacts are available:

1. Complete the platform inventory and establish which repositories the assessment can inspect.
2. For each accessible mobile codebase, locate app variants, CI, tests, release configuration, architecture records, and product documentation.
3. Search each native codebase for SDKs, permissions, app extensions, storage, authentication, push, deep links, analytics, experiments, and platform-specific behavior.
4. Cite repository names plus file paths and line numbers so evidence remains attributable when codebases are separate.
5. Ask stakeholders only for missing codebase locations or for product, organizational, and operational facts the repositories cannot establish.

Use interview assessment when the repository is unavailable or material evidence remains missing:

1. Start with the measurable delivery or business problem unless the user already supplied it.
2. Ask exactly one decision-changing question per turn.
3. Explain in one sentence which path, risk, or assumption the answer affects.
4. Challenge vague or contradictory answers with a narrower follow-up instead of accepting them as evidence.
5. Record the answer, update the evidence state, and choose the next highest-impact unknown.
6. Stop grilling when another answer cannot change the recommendation, confidence, or checkpoint.

Before the evidence gate passes, every response must contain only:

**Question:** [one question]

**Why it matters:** [one sentence]

Do not include a questionnaire, path recommendation, checkpoint, or implementation guidance during these turns. If the user pauses the interview, return the current evidence state and the single highest-impact unknown without pretending the assessment is complete.

Interview turn gate: one answer has been requested, its decision impact is explicit, and no second question appears.

1. Collect Decision Evidence

State the decision, deadline, current alternative, and measurable driver. A framework preference is not a driver.

Inspect these dimensions:

For an OTA-dependent plan, require an owner plus runtime compatibility, rollout, observability, rollback or republish, and audit policy. OTA availability alone is not a migration benefit.

Use a small migration core that combines existing product and native knowledge with React Native migration expertise. Ask only for missing facts that could change the decision; expose the rest as assumptions.

Gate: every dimension has evidence or an explicit unknown, and every path-blocking unknown is named.

2. Choose a Path

Choose one outcome and state why the alternatives lose.

Treat Path C as Callstack's emerging post-2025 operating model, not an industry benchmark. Agent access makes behavioral porting more viable; only a measured checkpoint on this product establishes speed and quality.

After Path A is accepted, hand implementation planning to react-native-brownfield-migration. Do not repeat its Expo, XCFramework, AAR, or host-integration guidance.

Gate: one outcome is supported by decisive evidence, rejected alternatives have reasons, and confidence reflects evidence quality.