2.1. Employees’ Job Crafting and Work Engagement
In terms of job design, a top-down approach in which tasks that are designed and structured by an organization are assigned to its members, such as the job characteristics model [
18], has traditionally been pervasive. However, as the turbulence of business environments has increased, the perspective on job design has changed [
19]. In conditions of high uncertainty, it is almost impossible for managers to forecast all contingencies in advance and to formalize specific tasks for employees with any precision [
20]. Instead, since Wrzesniewski and Dutton [
21] introduced the notion of job crafting as a self-initiated form of behavior in which employees proactively shape the boundaries of their jobs so as to align them with their own preferences and abilities, a bottom-up approach has emerged whereby job incumbents play an active role in altering their own tasks for themselves.
A representative version of the bottom-up approach is known as job crafting, conceptualizations of which have evolved into two major streams. On the one hand, the introducers of job crafting define it as “the physical and cognitive changes individuals make in the task or relational boundaries of their work”, delineating the types of job crafting as task crafting (“altering the form or number of activities one engages in while doing the job”), relational crafting (“exercising discretion over with whom one interacts while doing the job”), and cognitive crafting (“altering how one sees the job”) [
21] (pp. 179–180). On the other hand, while expanding the job demands-resources (JD-R) model, some scholars describe job crafting as “the changes that employees may make to balance their job demands (all aspects of the job that require sustained physical and/or psychological effort or skill) and job resources (those aspects of the job that are either/or functional in achieving work goals) with their personal abilities and needs” [
22] (p. 174). The latter further identify the forms of job crafting as “increasing structural job resources”, “increasing social job resources”, and “increasing challenging job demands”, and “decreasing hindering job demands” [
22] (p. 174). In a similar vein, others classify job crafting into “decreasing hindering job demands”, “increasing social job resources”, “increasing challenging job demands”, and “increasing structural job resources” [
23] (p. 367), and categorize it into “increasing challenging demands”, “decreasing social demands”, “increasing social job resources”, “increasing quantitative demands”, and “decreasing hindering demands” [
24] (p. 376).
Meanwhile, work engagement is described as “a positive, fulfilling, work-related state of mind that is characterized by vigor (high levels of energy and mental resilience while working), dedication (a sense of significance, enthusiasm, inspiration, pride, and challenge), and absorption (being fully concentrated and deeply engrossed in one’s work, whereby time passes quickly)” [
25] (pp. 74–75) As employees become more engaged, they approach their work more energetically, enthusiastically, and engrossedly, and in turn, expand the view of their roles and take on a broader set of activities in the workplace [
1,
26]. As a result, when compared to disengaged employees, engaged workers more frequently exhibit in-role, extra-role, and proactive behaviors [
14,
27,
28], and show lower turnover intention [
29]. Organizations that retain engaged members achieve superior business performance in terms of profitability and productivity [
3]. Additionally, engaged employees enjoy good mental health instead of experiencing symptoms, such as distress and depression [
2].
Researchers interested in the association between job crafting and work engagement have found that job crafters tend to become engaged in their work (e.g., [
9,
10,
11]). Yet, some scholars studying job crafting based on the expanded JD-R model have yielded results that differed from those that were expected for the relationships between the types or forms of job crafting and work engagement. For example, increasing social job resources, decreasing social job demands, and decreasing hindering job demands have, in instances, been found to be unrelated to work engagement [
23,
24], and decreasing hindering job demands has even been identified as being negatively related to work engagement [
22]. We thus attempt to investigate the relationship between job crafting and work engagement based on the definition by Wrzensniewski and Dutton [
21] in accordance with the original concept of job crafting. In particular, this study focuses on the task facet of job crafting, because it has been recognized as the main form of job crafting in the previous research (e.g., [
30]). Assuming that job crafting is likely to have a positive relationship with work engagement, we examine the mediating role of PsyCap and the moderating role of coworker support in the relationship below.
2.2. Mediating Role of Psychological Capital
Luthans and colleagues originated the construct of PsyCap to capture one’s psychological capacities and personal resources, defining it as “an individual’s positive psychological state of development” that contains the following four resources: “self-efficacy (having confidence to take on and put in the necessary effort to succeed at challenging tasks)”, “hope (persevering toward goals and, when necessary, redirecting paths to goals)”, “optimism (making a positive attribution about succeeding now and in the future), and resilience (when beset by problems and adversity, sustaining and bouncing back and even beyond)” [
31] (p. 3). As PsyCap inherently has a malleable and developmental property, it has the potential to be enhanced through training or practice [
32,
33]. PsyCap also has been found to influence various worker outcomes, such as attitudes, behavior, performance, and well-being [
34,
35]. In this way, PsyCap might not only be developed and improved, but it could also affect employees’ work lives. Further, work engagement reflects the active investment of one’s personal resources in conducting his or her work [
4,
13,
14]. Accordingly, we believe that PsyCap is suitable for the expectation of this study that PsyCap will play the mediating role in linking job crafting with work engagement.
We firstly anticipate that when workers craft their tasks they will feel enhanced PsyCap. Specifically, verifying employees’ capabilities with regard to new work-related activities in their work environment could benefit mastery experiences, resulting in higher levels of self-efficacy [
36]. Jobs that are enriched by crafting individuals’ task boundaries are also likely to improve their abilities to develop or identify alternative pathways to reach their goals, which would consequently foster their hope [
37]. Moreover, job crafters should maintain a positive evaluation of various events occurring in the workplace by exercising control over their work conditions, and as a result, experience increased the levels of optimism [
11]. Lastly, job crafting tends to enable the ability to handle and overcome difficult work situations, which would be helpful to employees in terms of building or improving their resilience [
38]. Based on this reasoning, it is expected that job crafting will positively influence PsyCap comprising hope, optimism, self-efficacy, and resilience. This study further predicts that workers with higher levels of PsyCap are more likely to engage in their work. In practice, this means that employees with high PsyCap are inclined to be confident in their competencies to perform the tasks, to create possible means and alternatives to accomplish those tasks, to believe that they will obtain beneficial work outcomes, and to adapt to challenging work situations [
39,
40]. The benefits arising from these personal resources have been reported to make a great contribution to their energetic, enthusiastic, and engrossed approach to the work, as well as the quality of their working lives [
8,
41].
In sum, if employees craft their tasks, they become self-efficacious, optimistic, hopeful, and resilient, and eventually, they are likely to be vigorous, dedicated, and absorbed in their work. In other words, it is expected that job crafting will foster PsyCap, which in turn will promote work engagement. Accordingly, we suggest the following hypothesis:
Hypothesis 1 (H1). Psychological capital mediates the positive association between job crafting and work engagement.
2.3. Moderating Role of Coworker Support
Social support from useful social interaction with people in the workplace is considered to be one of the job resources that is beneficial to one’s work conduct and personal functioning [
42]. Researchers generally recognize that employees’ experiences in performing their work are greatly affected by their acquisition of social support with the accumulated evidence, indicating that social support functions to protect against the harmful impacts of job demands [
15,
43]. It is thus expected that there seems to be a complementary association between job crafting and social support. That is, as job crafters receive social support from others in the workplace, their levels of PsyCap will become higher.
Yet, we notice that since social support within an organization is to be found horizontally from coworkers and vertically from supervisors, it can be divided into coworker support and supervisor support. Further, we posit that coworker support rather than supervisor support will function as a critical boundary condition that links job crafting to PsyCap for the following two reasons. First, job crafting usually takes place at work without the knowledge or approval of supervisors [
16,
17]. That is, employees are inclined to alter work-related procedures or the scope of their work according to their own judgment. Therefore, it is probable that the influence of supervisors on employees’ job crafting efforts or the results of those endeavors is negligible. Second, as compared to supervisor support, coworker support tends to be more valued and consistent, and less influenced by organizational politics [
44]. As coworkers comprise the majority of ‘others’ with whom a job incumbent interacts during his or her work, he or she is more frequently exposed to coworkers than to supervisors [
45]. Under this condition, the sources of meaningful social support for job crafters seem to be not supervisors but coworkers.
Supportive work environments that derive from helpful coworkers provide an employee with work-related assistance, informative advice, and emotional empathy [
45]. Such instrumental and emotional help in the workplace leads the employee to drive for new challenges, to experiment, to make changes, and to embrace their own creativity [
46]. Accordingly, the support that a worker receives from his or her coworkers is expected to have a significant impact on the continuance and outcome of the efforts that the focal worker makes regarding job crafting. In addition, coworker support enables a job incumbent to feel that his or her personal resources are not subject to loss or insufficiency [
47]. When employees craft their tasks under conditions of high coworker support, they are more likely to feel that they have abundant personal resources. With the above discussion in mind, we propose the following hypothesis:
Hypothesis 2 (H2). Coworker support amplifies the positive association between job crafting and psychological capital, such that the association is larger among employees with high coworker support than those with low coworker support.